Skip to content

1 - HugeGraph (OLTP)

DeepWiki provides real-time updated project documentation with more comprehensive and accurate content, suitable for quickly understanding the latest project information.

📖 https://deepwiki.com/apache/hugegraph

GitHub Access: https://github.com/apache/hugegraph

1.1 - HugeGraph Server Quick Start

1 HugeGraph Server Overview

apache/hugegraph is the main repository for the HugeGraph graph database. Its top-level modules include hugegraph-server, hugegraph-pd, and hugegraph-store. This page describes the hugegraph-server module and the service it runs.

The hugegraph-server module contains hugegraph-core, hugegraph-api, hugegraph-dist, and storage adapters. Core implements the property graph model, transactions, and TinkerPop interfaces. API provides the HTTP service and delegates client requests to Core. Graph data is stored in RocksDB (the default standalone backend), HStore (distributed), or HBase.

⚠️ Version note: This page follows HugeGraph 1.7.0 through the master branch and covers only RocksDB, HStore, and HBase. For other legacy backends and their configuration, see the HugeGraph 1.5.x documentation.

Naming: HugeGraph means the overall project or main repository, hugegraph-server is the Server module in that repository, and HugeGraphServer is the Java class for the service process. This page uses “Server service” for a running graph database service.

2 Dependency for Building/Running

2.1 Install Java 11 (JDK 11)

The hugegraph-server module in HugeGraph 1.7.0 is compiled with Java 11. Running and building it from source require Java 11 or later.

Before continuing, run java -version to confirm your JDK version.

Java 8 is no longer supported starting from 1.7.0. bin/hugegraph-server.sh refuses to start on anything older than Java 11.

The security check is on by default and installs HugeSecurityManager, which needs Java 11 to 23. JDK 24 removed the Security Manager (JEP 486), so on Java 24 or later you must start the service with the check disabled: bin/start-hugegraph.sh -s false.

Building from source also needs Maven 3.5.0 or later.

3 Deploy

There are four ways to deploy the Server service:

  1. Use a Docker container for test or development.
  2. Download the binary tarball.
  3. Compile the source code.
  4. Use the legacy one-click deployment tool.

Do not expose Gremlin, Cypher, or other query endpoints directly to the public Internet. In production, enable authentication and authorization, restrict network access, and retain audit logs. See the Security Guide for deployment guidance.

3.1 Use Docker container (Convenient for Test/Dev)

You can refer to the Docker deployment guide.

You can use docker run -itd --name=server -p 8080:8080 -e PASSWORD=xxx hugegraph/hugegraph:1.7.0 to quickly start a Server instance using the RocksDB backend.

Optional:

  1. You can use docker exec -it server bash to enter the container for troubleshooting or other maintenance operations.
  2. You can use docker run -itd --name=server -p 8080:8080 -e PRELOAD="true" hugegraph/hugegraph:1.7.0 to preload a built-in sample graph at startup. You can verify it through the RESTful API. See 5.1.4 for details.
  3. You can use -e PASSWORD=xxx to enable authentication mode and set the admin password. See Config Authentication for details.

If you use Docker Desktop, you can set the options as follows:

Docker Desktop settings for a HugeGraph container

Note: The Docker Compose files use bridge networking (hg-net) and work on Linux and Mac (Docker Desktop). For the 3-node distributed cluster on Mac (Docker Desktop), allocate at least 12 GB of memory (Settings → Resources → Memory). On Linux, Docker uses host memory directly.

If you want a single, unified setup for multiple HugeGraph services, you can use docker compose. Four compose files are available in the docker/ directory:

TopologyCompose fileServices
Standalone (start here)docker-compose.yml1 RocksDB Server + 1 Hubble
Minimal HStoredocker-compose-hstore.yml1 PD + 1 Store + 1 Server + 1 Hubble
HA referencedocker-compose-3pd-3store-3server.yml3 PD + 3 Store + 3 Server + 1 Hubble
Source build override for the minimal HStore topologydocker-compose.dev.yml(used together with docker-compose-hstore.yml)
cd hugegraph/docker
# Keep the version aligned with the latest release, for example 1.x.0
HUGEGRAPH_VERSION=1.7.0 docker compose -f docker-compose.yml up -d --wait

The standalone topology publishes the Server on port 8080 and Hubble on 127.0.0.1:8088. HUGEGRAPH_VERSION selects the Server, PD, and Store image tags; Hubble is selected separately with HUBBLE_IMAGE.

The compose files read the administrator password from HUGEGRAPH_ADMIN_PASSWORD and the JWT secret from HUGEGRAPH_AUTH_TOKEN_SECRET, normally kept in a docker/.env file. A non-empty HUGEGRAPH_ADMIN_PASSWORD turns authentication on, and Hubble detects that mode by itself. With plain docker run, pass -e PASSWORD=xxx instead.

See docker/README.md for the full setup guide.

Note:

  1. HugeGraph Docker images are provided as a convenient way to start HugeGraph quickly, but they are not official ASF distribution artifacts. You can find more details in the ASF Release Distribution Policy.

  2. We recommend using a release tag (such as 1.7.0 or 1.x.0) for stable deployments. Use the latest tag only if you want the newest features still under development.

3.2 Download the binary tarball

You could download the binary tarball from the download page of the ASF site like this:

download-and-verify.sh
# 1.7.0 is a historical release from the incubation period, so its file name still includes "incubating"
wget https://downloads.apache.org/hugegraph/1.7.0/apache-hugegraph-incubating-1.7.0.tar.gz
tar zxf apache-hugegraph-incubating-1.7.0.tar.gz

# (Optional) verify the integrity with SHA512 (recommended)
shasum -a 512 apache-hugegraph-incubating-1.7.0.tar.gz
curl https://downloads.apache.org/hugegraph/1.7.0/apache-hugegraph-incubating-1.7.0.tar.gz.sha512

3.3 Source code compilation

Please ensure that the wget/curl commands are installed before compiling the source code

Download HugeGraph source code in either of the following 2 ways (so as the other HugeGraph repos/modules):

  • download the stable/release version from the ASF site
  • clone the unstable/latest version by GitBox(ASF) or GitHub
build-from-source.sh
# Way 1. download release package from the ASF site
wget https://downloads.apache.org/hugegraph/{version}/apache-hugegraph-incubating-src-{version}.tar.gz
tar zxf *hugegraph*.tar.gz

# (Optional) verify the integrity with SHA512 (recommended)
shasum -a 512 apache-hugegraph-incubating-src-{version}.tar.gz
curl https://downloads.apache.org/hugegraph/{version}/apache-hugegraph-incubating-{version}-src.tar.gz.sha512

# Way2 : clone the latest code by git way (e.g GitHub)
git clone https://github.com/apache/hugegraph.git

Compile and generate tarball

cd *hugegraph
# (Optional) use "-P stage" param if you build failed with the latest code(during pre-release period)
mvn package -DskipTests -ntp

A successful build includes the following line:

[INFO] BUILD SUCCESS

After a successful build, the generated distribution is the *hugegraph-*.tar.gz file in the repository root.

The default build bundles the rocksdb, hbase, and hstore backend modules, and records them in the backends option of the backend.properties resource inside the hugegraph-dist jar. To build a smaller distribution that carries RocksDB only, add -Drocksdb-only:

mvn package -DskipTests -ntp -Drocksdb-only
Outdated tools

3.4 One-click deployment (Outdated)

HugeGraph-Tools provides a one-click deployment command that downloads, extracts, configures, and starts the Server service and HugeGraph-Hubble. These tools are included in the HugeGraph-Toolchain distribution.

Of course, you should download the tarball of HugeGraph-Toolchain first.

# download toolchain binary package, it includes loader + tool + hubble
# please check the latest version (e.g. here is 1.7.0)
wget https://downloads.apache.org/hugegraph/1.7.0/apache-hugegraph-toolchain-incubating-1.7.0.tar.gz
tar zxf *hugegraph-*.tar.gz

# enter the tool's package
cd *hugegraph*/*tool* 

note: ${version} is the version, The latest version can refer to Download Page, or click the link to download directly from the Download page

The general entry script for HugeGraph-Tools is bin/hugegraph, Users can use the help command to view its usage, here only the commands for one-click deployment are introduced.

bin/hugegraph deploy -v {hugegraph-version} -p {install-path} [-u {download-path-prefix}]

{hugegraph-version} is the Server service and HugeGraphStudio version; see conf/version-mapping.yaml for supported mappings. {install-path} is the installation directory, while {download-path-prefix} optionally overrides the tarball download location. For example, deploy version 0.6 with bin/hugegraph deploy -v 0.6 -p services.

4 Config

If you need to quickly start HugeGraph just for testing, then you only need to modify a few configuration items (see next section). For detailed configuration introduction, please refer to configuration document and introduction to configuration items

5 Startup

5.1 Use a startup script to startup

Startup is divided into “first startup” and “non-first startup”. On the first startup, you need to initialize the backend database before starting the service.

If the service was stopped manually, or needs to be started again for any other reason, you can usually start it directly because the backend database is persistent.

When HugeGraphServer starts, it connects to the backend storage and checks its version information. If the backend has not been initialized, or if it was initialized with an incompatible version (for example, old-version data), HugeGraphServer will fail to start and report an error.

If you need to access HugeGraphServer externally, modify the restserver.url configuration item in rest-server.properties (the default is http://127.0.0.1:8080) and change it to the machine name or IP address.

Since the configuration (hugegraph.properties) and startup steps required by various backends are slightly different, the following will introduce the configuration and startup of each backend one by one.

Note: Configure Server Authentication before starting HugeGraphServer if you need Auth mode (especially for production or public network environments).

5.1.1 Distributed Storage (HStore)

Click to expand/collapse Distributed Storage configuration and startup method

Distributed storage is a new feature introduced after HugeGraph 1.5.0, which implements distributed data storage and computation based on HugeGraph-PD and HugeGraph-Store components.

To use the distributed storage engine, you need to deploy HugeGraph-PD and HugeGraph-Store first. See HugeGraph-PD Quick Start and HugeGraph-Store Quick Start.

After ensuring that both PD and Store services are started, modify the hugegraph.properties configuration of HugeGraph-Server:

backend=hstore
serializer=binary

# PD service address, multiple PD addresses are separated by commas, configure PD's RPC port
pd.peers=127.0.0.1:8686,127.0.0.1:8687,127.0.0.1:8688
# Simple example (with authentication)
gremlin.graph=org.apache.hugegraph.auth.HugeFactoryAuthProxy

# Specify storage backend hstore
backend=hstore
serializer=binary
store=hugegraph

# pd config
pd.peers=127.0.0.1:8686

A ready-made template for this backend ships as conf/graphs/hstore.properties.template. Copy it over conf/graphs/hugegraph.properties and adjust pd.peers.

The task scheduler is picked from the backend, so task.scheduler_type does not need to be set. hstore uses the distributed scheduler and every other backend uses the local one. The key is still accepted for upgrade compatibility, but it is ignored and logs a warning.

Then enable PD discovery in rest-server.properties (required for every HugeGraph-Server node):

usePD=true
# load the hugegraph.properties above from the graphs directory; the source default is false
graph.load_from_local_config=true

# notice: must have this conf in 1.7.0
pd.peers=127.0.0.1:8686,127.0.0.1:8687,127.0.0.1:8688
# If auth is needed
# auth.authenticator=org.apache.hugegraph.auth.StandardAuthenticator

If configuring multiple HugeGraph-Server nodes, you need to modify the rest-server.properties configuration file for each node, for example:

Node 1 (Master node):

usePD=true
restserver.url=http://127.0.0.1:8081
gremlinserver.url=http://127.0.0.1:8181
pd.peers=127.0.0.1:8686

rpc.server_host=127.0.0.1
rpc.server_port=8091

server.id=server-1
server.role=master

Node 2 (Worker node):

usePD=true
restserver.url=http://127.0.0.1:8082
gremlinserver.url=http://127.0.0.1:8182
pd.peers=127.0.0.1:8686

rpc.server_host=127.0.0.1
rpc.server_port=8092

server.id=server-2
server.role=worker

Also, you need to modify the port configuration in gremlin-server.yaml for each node:

Node 1:

host: 127.0.0.1
port: 8181

Node 2:

host: 127.0.0.1
port: 8182

Initialize the database:

cd *hugegraph-${version}
bin/init-store.sh

PD and Store own the metadata and the store for the hstore backend, so init-store skips graphs configured with it. Running it still creates the built-in admin account when authentication is on. In a deployment where the storage side already holds that account, set init_store.enabled=false in rest-server.properties to skip the whole step, which is what the Docker HStore topologies do.

Start the Server:

bin/start-hugegraph.sh

The startup sequence for using the distributed storage engine is:

  1. Start HugeGraph-PD
  2. Start HugeGraph-Store
  3. Initialize the database (only for the first time)
  4. Start HugeGraph-Server

Verify that the service is started properly:

curl http://localhost:8081/graphspaces/DEFAULT/graphs
# Should return: {"graphs":["hugegraph"]}

The sequence to stop the services should be the reverse of the startup sequence:

  1. Stop HugeGraph-Server
  2. Stop HugeGraph-Store
  3. Stop HugeGraph-PD
bin/stop-hugegraph.sh
Docker Distributed Cluster

Run the full distributed cluster (3 PD + 3 Store + 3 Server) with Docker Compose:

cd hugegraph/docker
HUGEGRAPH_VERSION=1.7.0 docker compose -f docker-compose-3pd-3store-3server.yml up -d --wait

Services communicate via container hostnames on the hg-net bridge network. Configuration is injected via environment variables:

# Server configuration, shared by server0, server1 and server2
HG_SERVER_BACKEND: hstore
HG_SERVER_PD_PEERS: pd0:8686,pd1:8686,pd2:8686
HG_SERVER_CLUSTER: hg
HG_SERVER_USE_PD: "true"
HG_SERVER_MIN_FREE_MEMORY: "0"
HG_SERVER_INIT_STORE_ENABLED: "false"
HG_SERVER_REQUIRE_AUTH_TOKEN_SECRET: "true"
STORE_REST: store0:8520
# per node, for example on server0
HG_SERVER_REST_URL: http://server0:8080

Because this topology sets HG_SERVER_REQUIRE_AUTH_TOKEN_SECRET: "true", the Servers refuse to start when a password is supplied without a shared JWT secret. Put both HUGEGRAPH_ADMIN_PASSWORD and HUGEGRAPH_AUTH_TOKEN_SECRET in docker/.env before starting it. The full variable reference is in the Docker Cluster guide.

Verify the cluster:

curl http://localhost:8080/versions
curl http://localhost:8620/v1/stores

To view runtime logs for any container use docker logs <container-name> (e.g. docker logs hg-pd0).

See docker/README.md for the full environment variable reference, port table, and troubleshooting guide.

5.1.2 RocksDB / ToplingDB

Click to expand/collapse RocksDB configuration and startup methods

RocksDB is an embedded database that does not require manual installation and deployment. GCC version >= 4.3.0 (GLIBCXX_3.4.10) is required. If not, GCC needs to be upgraded in advance

Update hugegraph.properties

backend=rocksdb
serializer=binary
rocksdb.data_path=.
rocksdb.wal_path=.

Initialize the database (required on the first startup, or a new configuration was manually added under ‘conf/graphs/’)

cd *hugegraph-${version}
bin/init-store.sh

Start server

bin/start-hugegraph.sh
Starting HugeGraphServer in daemon mode...
Connecting to HugeGraphServer (http://127.0.0.1:8080/graphs)....OK
Started [pid 21614]

ToplingDB (Beta): As a high-performance alternative to RocksDB, please refer to the configuration guide: ToplingDB Quick Start

5.1.3 HBase

Click to expand/collapse HBase configuration and startup methods

users need to install HBase by themselves, requiring version 2.0 or above,download link

Update hugegraph.properties

backend=hbase
serializer=hbase

# hbase backend config
hbase.hosts=localhost
hbase.port=2181
# Note: recommend to modify the HBase partition number by the actual/env data amount & RS amount before init store
# it may influence the loading speed a lot
#hbase.enable_partition=true
#hbase.vertex_partitions=10
#hbase.edge_partitions=30

Initialize the database (required on the first startup, or a new configuration was manually added under ‘conf/graphs/’)

cd *hugegraph-${version}
bin/init-store.sh

Start server

bin/start-hugegraph.sh
Starting HugeGraphServer in daemon mode...
Connecting to HugeGraphServer (http://127.0.0.1:8080/graphs)....OK
Started [pid 21614]

5.1.4 Create an example graph when startup

Pass the -p true argument when starting the script to enable preload, which creates a sample graph.

bin/start-hugegraph.sh -p true
Starting HugeGraphServer in daemon mode...
Connecting to HugeGraphServer (http://127.0.0.1:8080/graphs)......OK

And use the RESTful API to request HugeGraphServer and get the following result:

> curl "http://localhost:8080/graphspaces/DEFAULT/graphs/hugegraph/graph/vertices" | gunzip

{"vertices":[{"id":"2:lop","label":"software","type":"vertex","properties":{"name":"lop","lang":"java","price":328}},{"id":"1:josh","label":"person","type":"vertex","properties":{"name":"josh","age":32,"city":"Beijing"}},{"id":"1:marko","label":"person","type":"vertex","properties":{"name":"marko","age":29,"city":"Beijing"}},{"id":"1:peter","label":"person","type":"vertex","properties":{"name":"peter","age":35,"city":"Shanghai"}},{"id":"1:vadas","label":"person","type":"vertex","properties":{"name":"vadas","age":27,"city":"Hongkong"}},{"id":"2:ripple","label":"software","type":"vertex","properties":{"name":"ripple","lang":"java","price":199}}]}

This indicates the successful creation of the sample graph.

5.1.5 Startup script options

bin/start-hugegraph.sh accepts the following options. Every one of them takes a value, so write -d false, not a bare -d.

OptionValuesDefaultPurpose
-dtrue, falsetrueDaemon mode. With -d false the script stays in the foreground and forwards SIGTERM/SIGINT to the server.
-gzgc or ZGComit for G1GCGarbage collector to use. Only ZGC is accepted, any other value aborts the startup. ZGC needs Java 11 or later.
-mtrue, falsefalseInstall the cron-based monitor task (bin/start-monitor.sh). For VM and bare-metal deployments only.
-ptrue, falsefalsePreload the sample graph, as in 5.1.4.
-strue, falsetrueRun with the security check (HugeSecurityManager) enabled. It requires Java 11 to 23 and a readable conf/java-security.properties.
-jJVM optionsemptyExtra JVM options appended to the server command line.
-tseconds30How long to wait for the service to answer before reporting a failed startup.
-ytrue, falsefalseEnable the OpenTelemetry agent for traces.

bin/stop-hugegraph.sh accepts -m true|false (default true), which controls whether the cron monitor task is removed along with the service.

5.2 Use Docker to startup

In 3.1 Use Docker container, we introduced how to deploy hugegraph-server with Docker. You can also switch storage backends or preload a sample graph by setting the corresponding parameters.

5.2.1 Create an example graph when starting a server

Set the environment variable PRELOAD=true when starting Docker so that sample data is loaded during startup.

  1. Use docker run

    Use docker run -itd --name=server -p 8080:8080 -e PRELOAD=true hugegraph/hugegraph:1.7.0

  2. Use docker-compose

    Create a docker-compose.yml file like the following and set PRELOAD=true in the environment. example.groovy is a predefined script used to preload sample data. If needed, you can mount a new example.groovy script to change the preload data.

    version: '3'
    services:
      server:
        image: hugegraph/hugegraph:1.7.0
        container_name: server
        environment:
          - PRELOAD=true
          - PASSWORD=xxx
        volumes:
          - /path/to/yourscript:/hugegraph-server/scripts/example.groovy
        ports:
          - 8080:8080

    Use docker compose up -d to start the container.

And use the RESTful API to request HugeGraphServer and get the following result:

> curl "http://localhost:8080/graphspaces/DEFAULT/graphs/hugegraph/graph/vertices" | gunzip

{"vertices":[{"id":"2:lop","label":"software","type":"vertex","properties":{"name":"lop","lang":"java","price":328}},{"id":"1:josh","label":"person","type":"vertex","properties":{"name":"josh","age":32,"city":"Beijing"}},{"id":"1:marko","label":"person","type":"vertex","properties":{"name":"marko","age":29,"city":"Beijing"}},{"id":"1:peter","label":"person","type":"vertex","properties":{"name":"peter","age":35,"city":"Shanghai"}},{"id":"1:vadas","label":"person","type":"vertex","properties":{"name":"vadas","age":27,"city":"Hongkong"}},{"id":"2:ripple","label":"software","type":"vertex","properties":{"name":"ripple","lang":"java","price":199}}]}

This indicates that the sample graph was created successfully.

6. Access server

6.1 Service startup status check

Use jps to see a service process

jps
6475 HugeGraphServer

curl request RESTfulAPI

echo `curl -o /dev/null -s -w %{http_code} "http://localhost:8080/graphspaces/DEFAULT/graphs/hugegraph/graph/vertices"`

Return 200, which means the server starts normally.

6.2 Request Server

The RESTful API of HugeGraphServer includes various types of resources, typically including graph, schema, gremlin, traverser and task.

  • graph contains verticesedges
  • schema contains vertexlabelspropertykeysedgelabelsindexlabels
  • gremlin contains various Gremlin statements, such as g.v(), which can be executed synchronously or asynchronously
  • traverser contains various advanced queries including shortest paths, intersections, N-step reachable neighbors, etc.
  • task contains query and delete with asynchronous tasks
curl http://localhost:8080/graphspaces/DEFAULT/graphs/hugegraph/graph/vertices

explanation

  1. Since there are many vertices and edges in the graph, for list-type requests, such as getting all vertices, getting all edges, etc., the server will compress the data and return it, so when use curl, you get a bunch of garbled characters, you can redirect to gunzip for decompression. It is recommended to use the Chrome browser + Restlet plugin to send HTTP requests for testing.

    curl "http://localhost:8080/graphspaces/DEFAULT/graphs/hugegraph/graph/vertices" | gunzip
  2. The current default configuration of HugeGraphServer can only be accessed locally, and the configuration can be modified so that it can be accessed on other machines.

    vim conf/rest-server.properties
    
    restserver.url=http://0.0.0.0:8080

response body:

{
    "vertices": [
        {
            "id": "2lop",
            "label": "software",
            "type": "vertex",
            "properties": {
                "price": [
                    {
                        "id": "price",
                        "value": 328
                    }
                ],
                "name": [
                    {
                        "id": "name",
                        "value": "lop"
                    }
                ],
                "lang": [
                    {
                        "id": "lang",
                        "value": "java"
                    }
                ]
            }
        },
        {
            "id": "1josh",
            "label": "person",
            "type": "vertex",
            "properties": {
                "name": [
                    {
                        "id": "name",
                        "value": "josh"
                    }
                ],
                "age": [
                    {
                        "id": "age",
                        "value": 32
                    }
                ]
            }
        },
        ...
    ]
}

For the detailed API, please refer to RESTful-API

You can also visit localhost:8080/swagger-ui/index.html to check the API.

HugeGraph RESTful API endpoints in Swagger UI

When using Swagger UI to debug the API provided by HugeGraph, if HugeGraph Server turns on authentication mode, you can enter authentication information on the Swagger page.

Authorize button in the HugeGraph Swagger UI

Currently, HugeGraph supports setting authentication information in two forms: Basic and Bearer.

Basic and Bearer credential fields in the Swagger UI authorization dialog

7 Stop Server

cd apache-hugegraph-incubating-1.7.0/apache-hugegraph-server-incubating-1.7.0
bin/stop-hugegraph.sh

8 Debug Server with IntelliJ IDEA

Please refer to Setup Server in IDEA

1.2 - HugeGraph-PD Quick Start

1 HugeGraph-PD Overview

HugeGraph-PD (Placement Driver) is the metadata management component of HugeGraph’s distributed version, responsible for managing the distribution of graph data and coordinating storage nodes. It plays a central role in distributed HugeGraph, maintaining cluster status and coordinating HugeGraph-Store storage nodes.

PD keeps cluster metadata in an embedded RocksDB store under pd.data-path and replicates it across PD nodes with Raft, so a 3-node or 5-node PD cluster keeps serving while a minority of nodes is down. On top of that it registers and activates Store nodes, allocates and rebalances partitions, tracks Store heartbeats, and answers service discovery queries from Store and Server.

PD listens on three ports:

PortDefaultConfigured byUsed by
gRPC8686grpc.portStore and Server clients
REST8620server.portManagement, health checks, metrics
Raft8610raft.addressThe other PD nodes only

2 Prerequisites

2.1 Requirements

  • Operating System: Linux or macOS (Windows has not been fully tested)
  • Java version: ≥ 11
  • Maven version: ≥ 3.5.0

3 Deployment

There are two ways to deploy the HugeGraph-PD component:

  • Method 1: Download the tar package
  • Method 2: Compile from source

3.1 Download the tar package

Download the latest version of HugeGraph-PD from the Apache HugeGraph official download page:

# 1.7.0 is a historical release from the incubation period, so its file and directory names still include "incubating"
wget https://downloads.apache.org/hugegraph/1.7.0/apache-hugegraph-incubating-1.7.0.tar.gz
tar zxf apache-hugegraph-incubating-1.7.0.tar.gz
cd apache-hugegraph-incubating-1.7.0/apache-hugegraph-pd-incubating-1.7.0

3.2 Compile from source

# 1. Clone the source code
git clone https://github.com/apache/hugegraph.git

# 2. Build the project
cd hugegraph
mvn clean install -DskipTests=true

# 3. After a successful build, the PD directory and packages are located at
#    hugegraph-pd/apache-hugegraph-pd-{version}          (unpacked PD distribution)
#    hugegraph-pd/apache-hugegraph-pd-{version}.tar.gz   (PD only package, Linux build hosts only)
#    target/apache-hugegraph-{version}.tar.gz            (PD + Store + Server package)

To build only the PD distribution and the modules it depends on:

mvn clean package -pl hugegraph-pd/hg-pd-dist -am -DskipTests

The unpacked distribution contains just three directories: bin (start and stop scripts), conf (application.yml, application.yml.template, log4j2.xml, verify-license.json) and lib (the hg-pd-service jar).

3.3 Docker Deployment

The HugeGraph-PD Docker image is available on Docker Hub as hugegraph/pd.

Note: The following steps assume you have already cloned or pulled the HugeGraph main repository locally, or at least have its docker/ directory available.

Use the docker compose setup to deploy the complete 3-node cluster (PD + Store + Server):

cd hugegraph/docker
# Keep the version aligned with the latest release, for example 1.x.0
HUGEGRAPH_VERSION=1.7.0 docker compose -f docker-compose-3pd-3store-3server.yml up -d

A single PD plus a single Store and Server is also available as docker-compose-hstore.yml.

To run a single PD node via docker run, configuration is provided via environment variables:

docker run -d \
  -p 8620:8620 \
  -p 8686:8686 \
  -p 8610:8610 \
  -e HG_PD_GRPC_HOST=<your-ip> \
  -e HG_PD_RAFT_ADDRESS=<your-ip>:8610 \
  -e HG_PD_RAFT_PEERS_LIST=<your-ip>:8610 \
  -e HG_PD_INITIAL_STORE_LIST=<store-ip>:8500 \
  -v /path/to/data:/hugegraph-pd/pd_data \
  --name hugegraph-pd \
  hugegraph/pd:1.7.0

Environment variable reference:

VariableRequiredDefaultMaps toDescription
HG_PD_GRPC_HOSTYesn/agrpc.hostThis node’s hostname/IP for gRPC (e.g. pd0 in Docker, 192.168.1.10 on bare metal)
HG_PD_RAFT_ADDRESSYesn/araft.addressThis node’s Raft address (e.g. pd0:8610)
HG_PD_RAFT_PEERS_LISTYesn/araft.peers-listAll PD peers (e.g. pd0:8610,pd1:8610,pd2:8610)
HG_PD_INITIAL_STORE_LISTYesn/apd.initial-store-listExpected store gRPC addresses (e.g. store0:8500,store1:8500,store2:8500)
HG_PD_GRPC_PORTNo8686grpc.portgRPC server port
HG_PD_REST_PORTNo8620server.portREST API port
HG_PD_DATA_PATHNo/hugegraph-pd/pd_datapd.data-pathMetadata storage path
HG_PD_INITIAL_STORE_COUNTNo1pd.initial-store-countMinimum stores required for cluster availability

The entrypoint refuses to start if any of the four required variables is missing, and it turns the values above into a SPRING_APPLICATION_JSON override, so the packaged conf/application.yml does not need editing. Any key not covered by an HG_PD_* variable keeps the value from that file. JAVA_OPTS is passed through to the JVM.

Note: In Docker bridge networking, use container hostnames (e.g. pd0) for HG_PD_GRPC_HOST and HG_PD_RAFT_ADDRESS instead of IP addresses.

Deprecated aliases: GRPC_HOST, RAFT_ADDRESS, RAFT_PEERS, PD_INITIAL_STORE_LIST still work but log a deprecation warning. Use the HG_PD_* names for new deployments.

The image ships a HEALTHCHECK that polls GET /v1/health on port 8620 every 15 seconds, with a 90 second start period and 3 retries, so docker ps reports real PD health. The entrypoint runs the start script with -d false, so the container process is Java itself and Docker’s restart policy fires when it dies. The image also sets STDOUT_MODE=true, so docker logs <container-name> (e.g. docker logs hg-pd0) shows the PD log without exec-ing into the container.

See docker/README.md for the full cluster setup guide.

4 Configuration

The main configuration file for PD is conf/application.yml. This is the file the distribution ships:

spring:
  application:
    name: hugegraph-pd

management:
  metrics:
    export:
      prometheus:
        enabled: true
  endpoints:
    web:
      exposure:
        include: "*"

logging:
  config: 'file:./conf/log4j2.xml'

license:
  verify-path: ./conf/verify-license.json
  license-path: ./conf/hugegraph.license

grpc:
  # gRPC port for cluster mode
  port: 8686
  # Change to the actual local IPv4 address when deploying
  host: 127.0.0.1

server:
  # REST service port
  port: 8620

pd:
  # Storage path
  data-path: ./pd_data
  # Auto-expansion check cycle (seconds)
  patrol-interval: 1800
  # Minimum number of Store nodes required for cluster availability
  initial-store-count: 1
  # Store configuration information, format is IP:gRPC port
  initial-store-list: 127.0.0.1:8500

raft:
  # Raft address of this node
  address: 127.0.0.1:8610
  # Raft addresses of all PD nodes in the cluster
  peers-list: 127.0.0.1:8610

store:
  # Store offline time (seconds). After this time, the store is considered permanently unavailable
  max-down-time: 172800
  # Whether to enable store monitoring data storage
  monitor_data_enabled: true
  # Monitoring data interval
  monitor_data_interval: 1 minute
  # Monitoring data retention time
  monitor_data_retention: 1 day

partition:
  # Default number of replicas per partition
  default-shard-count: 1
  # Default maximum number of replicas per machine
  store-max-shard-count: 12

conf/application.yml.template is a second, unused copy with placeholders ($GRPC_PORT$, $RAFT_ADDRESS$ and so on) for deployment tooling that generates the file. PD always reads conf/application.yml, which the start script passes as -Dspring.config.location.

4.1 Configuration reference

Keys not present in conf/application.yml fall back to the built-in default listed below. Keys with no built-in default must be present, otherwise PD fails to start.

gRPC and REST

KeyShipped valueBuilt-in defaultDescription
grpc.host127.0.0.1none, requiredAddress this PD advertises for gRPC. Store and Server connect here, so set it to a reachable IPv4 address or hostname, never 127.0.0.1 or 0.0.0.0, in a distributed deployment.
grpc.port8686none, requiredgRPC port.
server.port8620none, requiredREST API port. Also the port reported in Raft member information.

application.yml.template also carries grpc.netty-server.max-inbound-message-size: 100MB, but PD sets the gRPC server’s inbound message limit to 1 GB in code, so that key has no effect.

Raft

KeyShipped valueBuilt-in defaultDescription
raft.address127.0.0.1:8610none, requiredRaft address of this node as host:port. Must be unique per node and must appear in raft.peers-list.
raft.peers-list127.0.0.1:8610none, requiredComma separated Raft addresses of every PD node, including this one. Must be identical on all nodes.
raft.enablenot settrueWhen true, metadata writes go through the Raft state machine. When false, PD writes straight to its local store with no replication.
raft.ip-whitelist.enablednot settrueWhen true, the Raft RPC port accepts connections only from the addresses resolved from raft.peers-list; other clients are dropped and logged as Blocked connection from <ip>. The allowlist is re-resolved when the peer list changes, but a peer that keeps its hostname and changes IP (a restarted container, for example) needs a PD restart.
raft.snapshotIntervalnot set300Seconds between Raft snapshots.
raft.rpc-timeoutnot set10000Raft RPC connect, request and install-snapshot timeout, in milliseconds.

PD core

KeyShipped valueBuilt-in defaultDescription
pd.data-path./pd_datanone, requiredMetadata directory. Holds the RocksDB store in rocksdb/ and the Raft log, metadata and snapshots in pd_raft/.
pd.patrol-interval1800300Seconds between patrol runs, which check partition health across stores and rebalance partition counts.
pd.initial-store-count13Minimum number of active Store nodes. Below this the cluster state becomes Cluster_Not_Ready and the cluster is treated as unavailable. Set it to the number of stores you deploy.
pd.initial-store-list127.0.0.1:8500emptyComma separated Store gRPC addresses (ip:port) that are activated automatically when they register. An entry may also carry a group id as store_address/group_id.
pd.cluster_idnot set1Cluster id, used to keep separate PD clusters apart.

Store management

KeyShipped valueBuilt-in defaultDescription
store.keepAlive-timeoutnot set300Seconds without a heartbeat after which a Store is treated as temporarily unavailable and its partition leaders move to other replicas.
store.max-down-time1728001800Seconds after which a Store is treated as permanently unavailable and its replicas are reallocated to other machines.
store.monitor_data_enabledtruefalseWhether to persist Store monitoring samples.
store.monitor_data_interval1 minute1 minuteSampling interval, written as <number> <unit> with unit one of second, minute, hour, day, month, year. The number defaults to 1 when omitted.
store.monitor_data_retention1 day1 dayHow long monitoring samples are kept, same format as above.

Partitions

KeyShipped valueBuilt-in defaultDescription
partition.default-shard-count13Number of replicas per partition. Use 3 for a production cluster.
partition.store-max-shard-count1224Maximum number of partition replicas one Store holds.

The initial partition count is derived from these two values and the size of pd.initial-store-list:

initial partitions = store count * partition.store-max-shard-count / partition.default-shard-count

Discovery, license and metrics

KeyShipped valueBuilt-in defaultDescription
discovery.heartbeat-try-countnot set3Number of missed heartbeats after which a registered client’s discovery entry is deleted.
license.verify-path./conf/verify-license.jsonnone, requiredPath to the license verification descriptor. Read by the /v1/license endpoints.
license.license-path./conf/hugegraph.licensenone, requiredPath to the license file. The distribution ships verify-license.json but no license file, so the license endpoints report an error until one is supplied.
auth.secret-keynot setbuilt-in constantHS256 secret used to sign the PD tokens handed back to internal clients.
management.metrics.export.prometheus.enabledtrueSpring Boot defaultExposes /actuator/prometheus.
management.endpoints.web.exposure.include"*"Spring Boot defaultActuator endpoints to expose.
logging.configfile:./conf/log4j2.xmlnoneLog4j2 configuration. Writes logs/hugegraph-pd.log, logs/hugegraph-pd_raft.log and logs/audit-hugegraph-pd.log.

Thread pools

KeyBuilt-in defaultDescription
thread.pool.grpc.core600Core size of the pool that serves gRPC calls.
thread.pool.grpc.max1000Maximum size of that pool.
thread.pool.grpc.queueunboundedQueue capacity of that pool.
job.uninterruptibleThreadPool.core0Core size of the background metadata job pool. A value of 0 or less means half the available processors.
job.uninterruptibleThreadPool.max256Maximum size of that pool.
job.uninterruptibleThreadPool.queueunboundedQueue capacity of that pool.

4.2 Single-node configuration

The shipped conf/application.yml already is a working single-node configuration. It is meant for development and testing: one PD node has no Raft quorum to lose, and partition.default-shard-count: 1 keeps a single replica per partition.

grpc:
  host: 127.0.0.1
  port: 8686
server:
  port: 8620
raft:
  address: 127.0.0.1:8610
  peers-list: 127.0.0.1:8610
pd:
  data-path: ./pd_data
  initial-store-count: 1
  initial-store-list: 127.0.0.1:8500
partition:
  default-shard-count: 1

4.3 Three-node cluster configuration

For a production cluster run 3 or 5 PD nodes, an odd number so Raft always has a quorum. A 3-node cluster tolerates one node failure. raft.peers-list must list every node and must be byte-for-byte identical on all of them, while grpc.host and raft.address differ per node.

Node 1 (192.168.1.10):

grpc:
  host: 192.168.1.10
  port: 8686
server:
  port: 8620
raft:
  address: 192.168.1.10:8610
  peers-list: 192.168.1.10:8610,192.168.1.11:8610,192.168.1.12:8610
pd:
  data-path: /data/pd
  initial-store-count: 3
  initial-store-list: 192.168.1.20:8500,192.168.1.21:8500,192.168.1.22:8500
partition:
  default-shard-count: 3

Node 2 (192.168.1.11) and node 3 (192.168.1.12) use the same file with grpc.host and raft.address changed to their own address:

# node 2
grpc:
  host: 192.168.1.11
raft:
  address: 192.168.1.11:8610
  peers-list: 192.168.1.10:8610,192.168.1.11:8610,192.168.1.12:8610

# node 3
grpc:
  host: 192.168.1.12
raft:
  address: 192.168.1.12:8610
  peers-list: 192.168.1.10:8610,192.168.1.11:8610,192.168.1.12:8610

To put all three PD nodes on one machine for testing, give each node its own pd.data-path and its own ports, for example raft 8610/8611/8612, gRPC 8686/8687/8688 and REST 8620/8621/8622.

In Docker bridge networking the same configuration comes from environment variables and uses container hostnames instead of IP addresses:

# pd0
HG_PD_GRPC_HOST: pd0
HG_PD_RAFT_ADDRESS: pd0:8610
HG_PD_RAFT_PEERS_LIST: pd0:8610,pd1:8610,pd2:8610
HG_PD_INITIAL_STORE_LIST: store0:8500,store1:8500,store2:8500
HG_PD_INITIAL_STORE_COUNT: 3

# pd1
HG_PD_GRPC_HOST: pd1
HG_PD_RAFT_ADDRESS: pd1:8610
HG_PD_RAFT_PEERS_LIST: pd0:8610,pd1:8610,pd2:8610

# pd2
HG_PD_GRPC_HOST: pd2
HG_PD_RAFT_ADDRESS: pd2:8610
HG_PD_RAFT_PEERS_LIST: pd0:8610,pd1:8610,pd2:8610

5 Start and Stop

5.1 Start PD

In the PD installation directory, execute:

./bin/start-hugegraph-pd.sh

The script requires a JDK of at least version 11 on PATH or in JAVA_HOME, and it exits without doing anything if it finds a Java process already using this installation’s conf directory.

Supported flags:

FlagValuesDefaultDescription
-dtrue, falsetrueDaemon mode. See the note below.
-gzgc, ZGCnot setGarbage collector. Leave the flag off for the default G1GC. Any other value, g1 included, aborts the start.
-jJVM optionsemptyExtra JVM options, for example -j "-Xmx8g -Xms8g".
-ytrue, falsefalseAttach the OpenTelemetry Java agent. The agent is downloaded into plugins/ on first use, its MD5 is verified, and traces are exported over gRPC to http://127.0.0.1:4317.

The -d flag controls daemon mode:

  • -d true (default): run as a background daemon; the script returns immediately.
  • -d false: run in foreground. The script execs Java, so the container or supervisor process IS Java. Use this when running under Docker or a process supervisor (systemd, supervisord) so crashes are detected and the service is restarted automatically.

Each flag also has an environment variable equivalent: DAEMON, GC_OPTION, USER_OPTION and OPEN_TELEMETRY. Setting JAVA_OPTIONS replaces the computed heap settings entirely; otherwise the script sizes the heap between 512 MB and 32 GB from available memory. Setting STDOUT_MODE=true leaves the JVM output on stdout instead of redirecting it to logs/hugegraph-pd-stdout.log, which is what the Docker image does.

After successful startup, you can see logs similar to the following in logs/hugegraph-pd-stdout.log:

YYYY-mm-dd xx:xx:xx [main] [INFO] o.a.h.p.b.HugePDServer - Started HugePDServer in x.xxx seconds (JVM running for x.xxx)

The process id is written to bin/pid.

5.2 Stop PD

In the PD installation directory, execute:

./bin/stop-hugegraph-pd.sh

The script reads bin/pid, sends the process a termination signal, waits up to 30 seconds for it to exit, and removes the pid file. If bin/pid is missing it reports that and exits successfully.

6 Startup Order in a Distributed Cluster

Start the components in this order:

  1. All PD nodes. They form the Raft group and elect a leader. Wait until every node answers GET /v1/health.
  2. All Store nodes. Each Store registers with PD over gRPC, and PD activates the ones listed in pd.initial-store-list. Wait until GET /v1/stores reports "state": "Up" for every Store.
  3. All Server nodes. A Server reads pd.peers and depends on PD reporting at least one live Store before partitions can be assigned.

The Docker Compose topologies enforce exactly this. Store containers wait on PD’s /v1/health healthcheck through depends_on with condition: service_healthy, Server containers wait the same way on the Store healthcheck, and the Server entrypoint then polls PD’s /v1/stores until a Store reports Up before it starts HugeGraph.

PD is also the last component to stop: shut down Server, then Store, then PD.

7 Verification

7.1 REST API authentication

Except for /actuator/*, /v1/health and /v1/prom/targets/*, every PD REST path requires an HTTP Basic Authorization header whose user name is one of the internal service names hg, store, hubble or vermeer. A request without the header is answered with:

{"status": -1, "error": "Unauthorized!"}

The password is not validated yet, so any value works. The Server’s own bin/wait-storage.sh uses store:admin and lets you override it with PD_AUTH_USER and PD_AUTH_PASSWORD, so the examples below use the same credentials:

curl -u store:admin http://localhost:8620/v1/stores

Warning: This check is only meant to separate HugeGraph’s own components from other traffic. Do not expose the PD REST or gRPC ports to an untrusted network. Restrict them with firewall rules or security groups, and keep raft.ip-whitelist.enabled on so the Raft port only accepts the configured peers.

7.2 Health check

GET /v1/health needs no credentials and is what the Docker healthcheck uses. It answers 200 with an empty body:

curl -i http://localhost:8620/v1/health

The Spring Boot actuator endpoint also works and is more readable:

curl http://localhost:8620/actuator/health

If it returns {"status":"UP"}, it indicates that the PD service has been successfully started.

7.3 Cluster and member status

Check the PD members and which node is the Raft leader:

curl -u store:admin http://localhost:8620/v1/members

The response carries pdList, the elected pdLeader, numOfService, numOfNormalService and a stateCountMap. In a healthy 3-node PD cluster numOfService and numOfNormalService are both 3 and exactly one member has role: "Leader".

GET /v1/cluster returns the same member list together with the Store list, graph list and overall cluster state, and GET / returns a short summary (leader address, cluster state, member count, store count, graph count, partition count).

7.4 Store status

You can also verify Store node status through the PD API:

curl -u store:admin http://localhost:8620/v1/stores

If the response shows state as Up, the corresponding Store node is running normally. The example below shows a single Store node. In a healthy 3-node deployment, the storeId list should contain three IDs, and stateCountMap.Up, numOfService, and numOfNormalService should all be 3.

{
  "message": "OK",
  "data": {
    "stores": [
      {
        "storeId": 8319292642220586694,
        "address": "127.0.0.1:8500",
        "raftAddress": "127.0.0.1:8510",
        "version": "",
        "state": "Up",
        "deployPath": "/Users/{your_user_name}/hugegraph/apache-hugegraph-incubating-1.7.0/apache-hugegraph-store-incubating-1.7.0/lib/hg-store-node-1.7.0.jar",
        "dataPath": "./storage",
        "startTimeStamp": 1754027127969,
        "registedTimeStamp": 1754027127969,
        "lastHeartBeat": 1754027909444,
        "capacity": 494384795648,
        "available": 346535829504,
        "partitionCount": 0,
        "graphSize": 0,
        "keyCount": 0,
        "leaderCount": 0,
        "serviceName": "127.0.0.1:8500-store",
        "serviceVersion": "",
        "serviceCreatedTimeStamp": 1754027127000,
        "partitions": []
      }
    ],
    "stateCountMap": {
      "Up": 1
    },
    "numOfService": 1,
    "numOfNormalService": 1
  },
  "status": 0
}

7.5 Other REST endpoints

All paths below are relative to http://<pd-host>:8620 and need the Basic header from section 7.1 unless noted.

Method and pathDescription
GET /Brief cluster statistics: leader, state, member count, store count, graph count, partition count
GET /v1/healthHealth check, no authentication required
GET /v1/clusterFull cluster statistics: PD members, stores, graphs, partitions
GET /v1/membersPD member list with roles and the elected leader
POST /v1/members/changeChange the Raft peer list, body {"peerList": "..."}
GET /v1/storesRegistered Store nodes with state and per-store statistics
GET /v1/store/{storeId}One Store node
POST /v1/store/{storeId}Update a Store’s state, body {"storeState": "..."}
DELETE /v1/store/{storeId}Remove a Store from the cluster
POST /v1/store/logStore state change log, body {"startTime": "...", "endTime": "..."}
GET /v1/storesAndStatsRaw Store metadata, for debugging
GET /v1/store_monitor/{storeId}Store monitoring samples as text
GET /v1/store_monitor/json/{storeId}Store monitoring samples as JSON
GET /v1/shardsEvery shard of every partition, with store id, role, state and progress
GET /v1/shardGroupsShard groups
GET /v1/shardGroupsCacheShard groups from PD’s in-memory cache
GET /v1/shardLeadersPartition leaders grouped by Store raft address
GET /v1/balanceLeadersRebalance partition leaders across Stores
GET /v1/partitionsPartition list with state and statistics
GET /v1/highLevelPartitionsPartitions with per-graph key counts and data sizes
GET /v1/partitionsAndStatsRaw partition metadata, for debugging
POST /v1/partitions/logPartition change log, body {"startTime": "...", "endTime": "..."}
GET /v1/resetPartitionStateReset the state of every partition
GET /v1/graphsGraph list
GET /v1/graph/**One graph by name
POST /v1/graph/**Update a graph’s partition count, body {"partitionCount": N}
GET /v1/graph/partitionSizeRangeMinimum and maximum partition count the cluster accepts
GET /v1/graph-spacesGraph space list
GET /v1/graph-spaces/**One graph space
POST /v1/graph-spaces/**Update a graph space
POST /v1/registryRegister a service instance for discovery
POST /v1/registryInfoQuery registered instances
GET /v1/allInfoAll registered instances
GET /v1/licenseLicense context
GET /v1/license/machineInfoIP and MAC addresses seen by the license check
GET /v1/task/patrolStoresRun the store patrol task now
GET /v1/task/patrolPartitionsRun the partition patrol task now
GET /v1/task/balancePartitionsRebalance partitions across Stores
GET /v1/task/splitPartitionsRun automatic partition splitting now
GET /v1/task/balanceLeadersRebalance partition leaders
GET /v1/task/compactInstruct Store nodes to compact the RocksDB files of their partitions
GET /v1/prom/targets/{appName}Prometheus service discovery targets, no authentication required
GET /v1/prom/targets-allPrometheus targets for all app types
GET /v1/prom/sd_configPrometheus HTTP service discovery config
GET /actuator/healthSpring Boot health, no authentication required
GET /actuator/metricsSpring Boot metrics, no authentication required
GET /actuator/prometheusPrometheus scrape endpoint, no authentication required

The two log endpoints take a time range as {"startTime": "...", "endTime": "..."}; yyyy-MM-dd HH:mm:ss and yyyy-MM-dd are among the accepted formats.

PD registers its own meters under the hg prefix, so /actuator/prometheus exposes hg_up, hg_graphs, hg_stores and hg_terms alongside the standard JVM metrics, plus per-graph partition and size meters once graphs exist.

1.3 - HugeGraph-Store Quick Start

1 HugeGraph-Store Overview

HugeGraph-Store is the storage node component of HugeGraph’s distributed version, responsible for actually storing and managing graph data. It works in conjunction with HugeGraph-PD to form HugeGraph’s distributed storage engine, providing high availability and horizontal scalability.

Each Store node keeps graph data in RocksDB and replicates it with Raft (JRaft): every partition is a separate Raft group, so a partition survives the loss of a minority of its replicas. Store nodes do not know about each other directly. They register with PD, receive their partition assignment from PD, and report state back over a heartbeat. HugeGraph-Server reaches Store over gRPC after looking up partition locations in PD.

2 Prerequisites

2.1 Requirements

  • Operating System: Linux or macOS (Windows has not been fully tested)
  • Java version: ≥ 11 (enforced by the build and re-checked by bin/start-hugegraph-store.sh)
  • Maven version: ≥ 3.5.0
  • Deploy HugeGraph-PD first for multi-node deployment

3 Deployment

There are two ways to deploy the HugeGraph-Store component:

  • Method 1: Download the tar package
  • Method 2: Compile from source

3.1 Download the tar package

Download the latest version of HugeGraph-Store from the Apache HugeGraph official download page:

# 1.7.0 is a historical release from the incubation period, so its file and directory names still include "incubating"
wget https://downloads.apache.org/hugegraph/1.7.0/apache-hugegraph-incubating-1.7.0.tar.gz
tar zxf apache-hugegraph-incubating-1.7.0.tar.gz
cd apache-hugegraph-incubating-1.7.0/apache-hugegraph-store-incubating-1.7.0

3.2 Compile from source

# 1. Clone the source code
git clone https://github.com/apache/hugegraph.git

# 2. Build the project
cd hugegraph
mvn clean install -DskipTests=true

# 3. After a successful build, the Store directory and complete distribution package are located at
#    hugegraph-store/apache-hugegraph-store-{version}
#    target/apache-hugegraph-{version}.tar.gz

To build Store alone instead of the whole repository, build hugegraph-struct first, because Store depends on it:

mvn install -pl hugegraph-struct -am -DskipTests
mvn clean package -pl hugegraph-store/hg-store-dist -am -DskipTests

The assembled directory contains only bin/, conf/ and lib/hg-store-node-{version}.jar.

3.3 Docker Deployment

The HugeGraph-Store Docker image is available on Docker Hub as hugegraph/store.

Note: The following steps assume you have already cloned or pulled the HugeGraph main repository locally, or at least have its docker/ directory available.

Two compose files include Store:

Compose fileTopologyUse
docker-compose-hstore.yml1 PD + 1 Store + 1 Server + 1 HubbleSmallest distributed setup
docker-compose-3pd-3store-3server.yml3 PD + 3 Store + 3 Server + 1 HubbleMulti-node reference
cd hugegraph/docker
# Keep the version aligned with the latest release, for example 1.x.0

# Minimal distributed deployment
HUGEGRAPH_VERSION=1.7.0 docker compose -f docker-compose-hstore.yml up -d --wait

# Or the multi-node cluster
HUGEGRAPH_VERSION=1.7.0 docker compose -f docker-compose-3pd-3store-3server.yml up -d

To run a single Store node via docker run:

docker run -d \
  -p 8520:8520 \
  -p 8500:8500 \
  -p 8510:8510 \
  -e HG_STORE_PD_ADDRESS=<pd-ip>:8686 \
  -e HG_STORE_GRPC_HOST=<your-ip> \
  -e HG_STORE_RAFT_ADDRESS=<your-ip>:8510 \
  -v /path/to/storage:/hugegraph-store/storage \
  --name hugegraph-store \
  hugegraph/store:1.7.0

Environment variable reference:

VariableRequiredDefaultMaps toDescription
HG_STORE_PD_ADDRESSYesn/apdserver.addressPD gRPC addresses (e.g. pd0:8686,pd1:8686,pd2:8686)
HG_STORE_GRPC_HOSTYesn/agrpc.hostThis node’s hostname/IP for gRPC (e.g. store0)
HG_STORE_RAFT_ADDRESSYesn/araft.addressThis node’s Raft address (e.g. store0:8510)
HG_STORE_GRPC_PORTNo8500grpc.portgRPC server port
HG_STORE_REST_PORTNo8520server.portREST API port
HG_STORE_DATA_PATHNo/hugegraph-store/storageapp.data-pathData storage path

The entrypoint turns these into a SPRING_APPLICATION_JSON overlay on top of conf/application.yml, then runs bin/start-hugegraph-store.sh -d false -j "$JAVA_OPTS". Any key not covered by the table above still has to be edited in conf/application.yml, or supplied through your own SPRING_APPLICATION_JSON.

Image details:

  • JAVA_OPTS defaults to -XX:+UnlockExperimentalVMOptions -XX:+UseContainerSupport -XX:MaxRAMPercentage=50 -XshowSettings:vm
  • STDOUT_MODE=true, so Java logs go to the container stdout instead of logs/hugegraph-store-server.log
  • HEALTHCHECK calls GET http://localhost:8520/v1/health every 15s after a 90s start period
  • The image declares EXPOSE 8520; publish 8500 and 8510 yourself when Server or other Store nodes need to reach the container from outside the Docker network

Note: In Docker bridge networking, use container hostnames (e.g. store0) for HG_STORE_GRPC_HOST instead of IP addresses.

Deprecated aliases: PD_ADDRESS, GRPC_HOST, RAFT_ADDRESS still work but log a deprecation warning. Use the HG_STORE_* names for new deployments.

4 Configuration

Store reads two files from conf/:

  • application.yml, the main configuration file (PD address, ports, Raft, data path)
  • application-pd.yml, pulled in by spring.profiles.include: pd in application.yml, holding the RocksDB memory settings and the Actuator exposure

4.1 application.yml

This is the file shipped in the distribution package:

pdserver:
  # PD service address, multiple PD addresses separated by commas
  address: localhost:8686

management:
  metrics:
    export:
      prometheus:
        enabled: true
  endpoints:
    web:
      exposure:
        include: "*"

grpc:
  # grpc service address
  host: 127.0.0.1
  port: 8500
  netty-server:
    max-inbound-message-size: 1000MB
raft:
  # raft cache queue size
  disruptorBufferSize: 1024
  address: 127.0.0.1:8510
  max-log-file-size: 600000000000
  # Snapshot generation interval, in seconds
  snapshotInterval: 1800
server:
  # rest service address
  port: 8520

app:
  # Storage path, support multiple paths, separated by commas
  data-path: ./storage
  #raft-path: ./storage

spring:
  application:
    name: store-node-grpc-server
  profiles:
    active: default
    include: pd

logging:
  config: 'file:./conf/log4j2.xml'
  level:
    root: info

4.2 application-pd.yml

management:
  metrics:
    export:
      prometheus:
        enabled: true
  endpoints:
    web:
      exposure:
        include: "*"

rocksdb:
  # rocksdb total memory usage, force flush to disk when reaching this value
  total_memory_size: 32000000000
  # memtable size used by rocksdb
  write_buffer_size: 32000000
  # For each rocksdb, the number of memtables reaches this value for writing to disk.
  min_write_buffer_number_to_merge: 16

4.3 Configuration reference

“Shipped” is the value in the two files above. “Code default” is what the node falls back to when the key is absent, and is the value to rely on for keys the template does not list.

Core

KeyShippedCode defaultMeaning
pdserver.addresslocalhost:8686requiredPD gRPC endpoints, comma separated. Store registers itself here and receives its partition assignment. Must be PD’s grpc.port, not its REST port.
grpc.host127.0.0.1requiredAddress this node advertises for its own gRPC service. Set it to a routable IP or hostname, 127.0.0.1 is only usable for a single-machine setup.
grpc.port8500requiredgRPC port. Server and the Store client connect here.
grpc.netty-server.max-inbound-message-size1000MBgRPC defaultMaximum size of a single inbound gRPC message. Bound by the grpc-spring-boot-starter Netty server.
grpc.server.wait-timenot set3600Seconds a scan stream waits for the client to consume a page before the server aborts it.
server.port8520requiredREST and Actuator port. Also reported to PD as the rest.port label.

Raft

KeyShippedCode defaultMeaning
raft.address127.0.0.1:8510requiredRaft service address of this node, host:port. Must be reachable from every other Store node. There is no peer list to configure: PD tells each node which peers belong to a partition’s Raft group.
raft.disruptorBufferSize10240Raft task queue size. 0 derives it from rocksdb.total_memory_size, by rounding that size in GB to the nearest power of two and multiplying by 32.
raft.max-log-file-size60000000000050000000000Maximum byte size of Raft logs.
raft.snapshotInterval1800300Seconds between Raft snapshots.
raft.snapshotLogIndexMarginnot set0Minimum applied-index distance since the last snapshot before a snapshot is actually written. 0 disables the distance check.
raft.rpc-timeoutnot set10000Raft RPC timeout in milliseconds.
raft.metricsnot settrueCollect JRaft node metrics, readable at /metrics/raft.
raft.useRocksDBSegmentLogStoragenot settrueStore Raft logs in the RocksDB segment log storage.
raft.maxSegmentFileSizenot set67108864Segment log file size in bytes (64 MB).
raft.maxReplicatorInflightMsgsnot set256Maximum in-flight replication requests per follower.
raft.maxEntriesSizenot set256Maximum number of entries in one AppendEntries request.
raft.maxBodySizenot set524288Maximum byte size of one AppendEntries request.
ave-logEntry-size-rationot set0.95Smoothing ratio used to estimate the average log entry size. Note that this key sits at the top level, not under raft.

Storage and labels

KeyShippedCode defaultMeaning
app.data-path./storagestoreRocksDB data directory. Multiple paths separated by commas spread partitions over several disks.
app.raft-pathcommented outemptyDirectory for Raft logs and snapshots. Falls back to app.data-path when empty.
app.fake-pdnot setfalseBuilt-in PD mode for standalone testing. Do not use it in production.
app.placeholder-sizenot set10Size in GB of a placeholder file created in each data path at startup, so space can be freed in an emergency. 0 disables it.
app.label.<name>not setnoneArbitrary key/value labels sent to PD in the store heartbeat. The node adds rest.port on its own.

RocksDB

KeyShippedCode defaultMeaning
rocksdb.total_memory_size3200000000051539607552Memory budget shared by all RocksDB instances on this node. When absent or 0, the node uses the JVM max heap instead.
rocksdb.write_buffer_size3200000033554432Memtable size in bytes. When absent or 0, the node uses total_memory_size / 1000.
rocksdb.min_write_buffer_number_to_merge1616Number of memtables merged together before a flush.
rocksdb.write_buffer_rationot set0.66Share of total_memory_size given to the write cache. The rest becomes the block cache.

Any other option defined in org/apache/hugegraph/rocksdb/access/RocksDBOptions.java can be added under the same rocksdb: block, for example rocksdb.max_background_jobs, rocksdb.level0_file_num_compaction_trigger or rocksdb.bloom_filter_bits_per_key.

Thread pools

KeyCode defaultMeaning
thread.pool.grpc.core600Core threads serving gRPC requests.
thread.pool.grpc.max1000Maximum gRPC threads.
thread.pool.grpc.queue2147483647gRPC task queue capacity.
thread.pool.scan.core128Core threads serving scans. 0 means 4 times the CPU count.
thread.pool.scan.max1000Maximum scan threads.
thread.pool.scan.queue0Scan task queue capacity.

Query pushdown

KeyCode defaultMeaning
query.push-down.threads1500Thread pool size for pushed-down queries.
query.push-down.fetch_batch20000Rows fetched per request.
query.push-down.fetch_timeout300000Fetch timeout in milliseconds.
query.push-down.memory_limit_count50000Row limit for in-memory operations such as sorting.
query.push-down.index_size_limit_count50000Index sst file size limit in kB.

Background jobs

KeyCode defaultMeaning
job.interruptableThreadPool.core128Core threads of the TTL cleaner pool. 0 means the CPU count.
job.interruptableThreadPool.max256Maximum threads of the TTL cleaner pool. 0 means 4 times the CPU count.
job.interruptableThreadPool.queue2147483647Queue capacity of the TTL cleaner pool.
job.uninterruptibleThreadPool.core0Core threads of the engine’s uninterruptible job pool. 0 means the CPU count.
job.uninterruptibleThreadPool.max256Maximum threads of the uninterruptible job pool.
job.uninterruptibleThreadPool.queue2147483647Queue capacity of the uninterruptible job pool.
job.cleaner.batch.size10000Keys deleted per batch by the TTL cleaner.
job.start-time0Hour of day (0 to 23) at which the daily TTL cleanup runs. Values outside that range fall back to 19.

Built-in PD mode

Only for single-node development and debugging, activated by app.fake-pd: true. The node then plays PD’s role itself and ignores pdserver.address.

KeyCode defaultMeaning
fake-pd.store-list''gRPC addresses of the Store nodes in the fake cluster.
fake-pd.peers-list''Raft addresses of the same nodes.
fake-pd.partition-count3Number of partitions.
fake-pd.shard-count3Replicas per partition.

Diagnostics

KeyCode defaultMeaning
arthas.telnetPort8566Arthas telnet port, used when /v1/arthasstart is called.
arthas.httpPort8565Arthas HTTP port.
arthas.ip0.0.0.0Arthas bind address.
arthas.disabledCommandsjadArthas commands to disable.

4.4 Per-node changes

For multi-node deployment, you need to modify the following configurations for each Store node:

  1. grpc.host and grpc.port (the address other components dial)
  2. raft.address (Raft protocol address)
  3. server.port (REST port)
  4. app.data-path (data storage path)

pdserver.address is the same on every node, it lists the whole PD cluster.

5 Start and Stop

5.1 Start Store

Ensure that the PD service is already started, then in the Store installation directory, execute:

./bin/start-hugegraph-store.sh

The script accepts four flags:

FlagValuesDefaultDescription
-dtrue, falsetrueDaemon mode. See below.
-gZGC, zgcnot setGarbage collector. Omit the flag for G1, which is the default. Any value other than ZGC or zgc aborts the start, including g1, even though the script’s own usage line suggests it.
-jJVM options stringemptyExtra JVM options, for example -j "-Xmx16g -Xms8g".
-ytrue, falsefalseAttach the OpenTelemetry Java agent, downloading it into plugins/ on first use, and export traces to 127.0.0.1:4317.

Daemon mode:

  • -d true (default): run as a background daemon. The script returns immediately and writes the Java pid to bin/pid.
  • -d false: run in the foreground. The script execs Java, so the container or supervisor process is Java itself. Use this under Docker or a process supervisor (systemd, supervisord) so crashes are detected and the service is restarted automatically.

JVM memory, unless you set JAVA_OPTIONS yourself: -Xms512m, and -Xmx set to half the free memory, clamped to the 512 MB to 2048 MB range. The script also adds -XX:MetaspaceSize=256M, a heap dump on out-of-memory into logs/, and a rolling GC log at logs/gc.log. Production nodes normally need a much larger heap, so pass one explicitly, for example -j "-Xmx32g -Xms32g".

The script refuses to start if ulimit -n or ulimit -u is below 1024, and it preloads jemalloc on x86_64 and arm64 when the shared object can be downloaded and verified.

After successful startup, you can see logs similar to the following in logs/hugegraph-store-server.log:

YYYY-mm-dd xx:xx:xx [main] [INFO] o.a.h.s.n.StoreNodeApplication - Started StoreNodeApplication in x.xxx seconds (JVM running for x.xxx)

5.2 Stop Store

In the Store installation directory, execute:

./bin/stop-hugegraph-store.sh

The script reads bin/pid, signals that process, and waits up to 30 seconds for it to exit before removing the pid file. If bin/pid is missing it exits without doing anything.

5.3 Restart Store

./bin/restart-hugegraph-store.sh

It sources the stop script and then the start script, and forwards the flags from section 5.1.

5.4 Startup order

  1. PD first. Each Store’s grpc.host:grpc.port should appear in PD’s pd.initial-store-list, otherwise PD registers the node in Pending state instead of bringing it to Up, and partition assignment never finishes.
  2. Store next. A Store started before PD is reachable is not fatal: the heartbeat thread keeps retrying registration and logs store heartbeat error: PD UNREACHABLE until PD answers.
  3. HugeGraph-Server last, once every Store node reports state: "Up". Server needs the partitions in place before it can initialize or open a graph.

The compose files encode the same order with depends_on: condition: service_healthy: Store waits for every PD healthcheck, and Server waits for every Store healthcheck.

6 Multi-Node Deployment Example

Below is a configuration example for a three-node deployment:

6.1 Three-Node Configuration Reference

  • 3 PD nodes
    • raft ports: 8610, 8611, 8612
    • rpc ports: 8686, 8687, 8688
    • rest ports: 8620, 8621, 8622
  • 3 Store nodes
    • raft ports: 8510, 8511, 8512
    • rpc ports: 8500, 8501, 8502
    • rest ports: 8520, 8521, 8522

6.2 Store Node Configuration

For the three Store nodes, the main configuration differences are as follows:

Node A:

grpc:
  port: 8500
raft:
  address: 127.0.0.1:8510
server:
  port: 8520
app:
  data-path: ./storage-a

Node B:

grpc:
  port: 8501
raft:
  address: 127.0.0.1:8511
server:
  port: 8521
app:
  data-path: ./storage-b

Node C:

grpc:
  port: 8502
raft:
  address: 127.0.0.1:8512
server:
  port: 8522
app:
  data-path: ./storage-c

All nodes should point to the same PD cluster:

pdserver:
  address: 127.0.0.1:8686,127.0.0.1:8687,127.0.0.1:8688

And every PD node should list all three Store gRPC addresses:

pd:
  initial-store-list: 127.0.0.1:8500,127.0.0.1:8501,127.0.0.1:8502

6.3 Docker Distributed Cluster Configuration

The distributed Store cluster definition is included in docker/docker-compose-3pd-3store-3server.yml. Each Store node gets its own hostname and environment variables:

# store0, published as 8500 (gRPC), 8510 (Raft), 8520 (REST)
HG_STORE_PD_ADDRESS: pd0:8686,pd1:8686,pd2:8686
HG_STORE_GRPC_HOST: store0
HG_STORE_GRPC_PORT: "8500"
HG_STORE_REST_PORT: "8520"
HG_STORE_RAFT_ADDRESS: store0:8510
HG_STORE_DATA_PATH: /hugegraph-store/storage

# store1, published as 8501, 8511, 8521
HG_STORE_GRPC_HOST: store1
HG_STORE_RAFT_ADDRESS: store1:8510

# store2, published as 8502, 8512, 8522
HG_STORE_GRPC_HOST: store2
HG_STORE_RAFT_ADDRESS: store2:8510

The container ports stay 8500/8510/8520 on every node, only the published host ports differ. The PD nodes set HG_PD_INITIAL_STORE_LIST: store0:8500,store1:8500,store2:8500 to match.

Store nodes start only after all PD nodes pass healthchecks (/v1/health), enforced via depends_on: condition: service_healthy.

To view runtime logs for a running Store container use docker logs <container-name> (e.g. docker logs hg-store0).

See docker/README.md for the full setup guide.

7 Verify Store Service

Confirm that the Store service is running properly:

curl http://localhost:8520/actuator/health

If it returns {"status":"UP"}, it indicates that the Store service has been successfully started.

GET /v1/health is the lighter check used by the Docker image and the compose files. It answers HTTP 200 with an empty body, so use curl -fsS and check the exit code rather than the output:

curl -fsS http://localhost:8520/v1/health && echo OK

7.1 Store REST endpoints

The Store node exposes these read-only endpoints on server.port:

MethodPathDescription
GET/v1/healthLiveness probe, HTTP 200 with an empty body
GET/actuator/healthSpring Boot Actuator health, {"status":"UP"}
GET/actuator/prometheusPrometheus scrape endpoint
GET/Node summary, leaderCount and partitionCount
GET/-/stateNode state, one of STARTING, ONLINE, STOPPING
GET/-/echo?name=<text>Echo check
GET/-/scanState of the running scan streams
GET/v1/partitionsAll Raft groups on this node with per-partition metrics. Add ?flags=accurate for exact key counts, which is slower.
GET/v1/partition/{id}One Raft group by partition id, including role, leader, peers and committed index
GET/metrics/systemHost CPU and memory metrics
GET/metrics/driveDisk metrics for the data paths
GET/metrics/raftJRaft node metrics, needs raft.metrics: true

Actuator and Prometheus are reachable because the shipped configuration sets management.endpoints.web.exposure.include: "*" and management.metrics.export.prometheus.enabled: true.

The node also serves maintenance endpoints that change state or run heavy work: PUT /-/state, GET /-/cleaner, GET /v1/partition/dump/{id}, GET /v1/partition/clean/{id}, POST /v1/compat?id=<partition>, GET /v1/arthasstart, POST /raft/options, and the /fix/* and /test/* groups. Use them only for troubleshooting, and keep the REST port off untrusted networks.

7.2 Check registration from PD

You can also check Store node status through the PD API:

curl -u store:admin http://localhost:8620/v1/stores

PD requires basic auth on its REST port. The user name must be one of hg, store, hubble, vermeer, and the password is not validated yet. A call with no credentials returns {"status":-1,"error":"Unauthorized!"}. Only /v1/health, /actuator/* and /v1/prom/targets/* are exempt.

If Store is configured successfully, the response should include status information for the current node, and state: "Up" means the node is running normally. A node stuck at Pending is usually missing from PD’s pd.initial-store-list.

The example below shows a single Store node. If all three nodes are configured correctly and running, the storeId list should contain three IDs, and stateCountMap.Up, numOfService, and numOfNormalService should all be 3.

{
  "message": "OK",
  "data": {
    "stores": [
      {
        "storeId": 8319292642220586694,
        "address": "127.0.0.1:8500",
        "raftAddress": "127.0.0.1:8510",
        "version": "",
        "state": "Up",
        "deployPath": "/Users/{your_user_name}/hugegraph/hugegraph-store/apache-hugegraph-store-{version}/lib/hg-store-node-{version}.jar",
        "dataPath": "./storage",
        "startTimeStamp": 1754027127969,
        "registedTimeStamp": 1754027127969,
        "lastHeartBeat": 1754027909444,
        "capacity": 494384795648,
        "available": 346535829504,
        "partitionCount": 0,
        "graphSize": 0,
        "keyCount": 0,
        "leaderCount": 0,
        "serviceName": "127.0.0.1:8500-store",
        "serviceVersion": "",
        "serviceCreatedTimeStamp": 1754027127000,
        "partitions": []
      }
    ],
    "stateCountMap": {
      "Up": 1
    },
    "numOfService": 1,
    "numOfNormalService": 1
  },
  "status": 0
}

2 - HugeGraph ToolChain

HugeGraph Toolchain includes the Java and Go clients, Loader, Hubble, Tools, Spark Connector, and SeaTunnel Sink/Source. Choose an entry by the task you need to complete, then open the component guide for its configuration and commands.

TaskStart hereBest for
Visualize graphsHubbleViewing and managing graphs in a Web UI
Import graph dataLoader, SeaTunnel Sink, Spark ConnectorImporting data directly or connecting an existing pipeline
Export or migrate graph dataTools, SeaTunnel SourceBackup, export, cross-graph migration, and continuous reads

Testing Guide: For running toolchain tests locally, please refer to HugeGraph Toolchain Local Testing Guide

DeepWiki provides real-time updated project documentation with more comprehensive and accurate content, suitable for quickly understanding the latest project information.

📖 https://deepwiki.com/apache/hugegraph-toolchain

Source repository: apache/hugegraph-toolchain

2.1 - Graph visualization

Use Hubble when you need to view graphs in a browser, run Gremlin, or manage graph connections. Hubble provides a visual interface for graph data, schemas, and tasks.

2.2 - HugeGraph-Hubble Quick Start

Deploy HugeGraph-Hubble for graph visualization, schema management, data import, and Gremlin or Cypher queries.

1 HugeGraph-Hubble Overview

⚠️ Security notice: Hubble listens on plain HTTP. Do not expose it to the public Internet or untrusted networks; terminate HTTPS in front of it and restrict access with IP/port allowlists. Hubble keeps no account database of its own: when the connected HugeGraph Server has authentication enabled, Hubble shows a sign-in page and forwards the credentials to the Server; when the Server allows anonymous access, there is no sign-in and the account pages are hidden.

Version note: This page follows hugegraph-toolchain master. Features that depend on newer Server, PD or Store versions are marked below and are unavailable on older Servers.

Testing Guide: For running HugeGraph-Hubble tests locally, please refer to HugeGraph Toolchain Local Testing Guide

HugeGraph-Hubble is HugeGraph’s web management interface. It connects to one HugeGraph Server, either directly or through PD in a distributed cluster, manages GraphSpaces, graphs and schemas, imports data, runs Gremlin and Cypher queries and built-in graph algorithms, and visualizes the results.

The platform mainly includes the following modules:

Graph Overview

Graph Overview lists GraphSpaces (in PD mode) and graphs. It creates, clones and clears graphs, loads demo graphs, opens the graph detail page with statistics and schema, and jumps to the query workbench.

Metadata Modeling

Metadata Modeling manages PropertyKeys, VertexLabels, EdgeLabels and IndexLabels of one graph, in list and graph views. Schema Templates keep reusable Groovy schemas per GraphSpace that can be applied when a graph is created.

Data Import

The data import page is intended for small-scale trials. For bulk or production imports, use HugeGraph Loader.

Data Sources register FILE, HDFS, JDBC and KAFKA sources. Import tasks are configured in four steps and can run once, on a cron schedule, or continuously for Kafka.

Graph Query

Graph Query runs Gremlin and Cypher statements in immediate or asynchronous mode and displays results as a graph (2D or 3D), a table, or JSON. It keeps execution records and favorite statements.

Built-in Graph Algorithms

Built-in Graph Algorithms provides forms for the Server’s OLTP traverser APIs (interactive exploration) and for OLAP jobs (cluster batch computation through HugeGraph Computer or Vermeer).

Async Tasks

Async Tasks lists background tasks such as Gremlin and Cypher tasks, algorithm tasks, metadata removal, index creation and rebuild, and Vermeer load or compute tasks, with detail, cancel and delete actions.

System and Operations

System and Operations covers the personal profile, account management with GraphSpace permission presets, and, in PD mode, the cluster overview and node details.

1.1 Compatibility

Hubble detects the authentication mode and the capabilities of the connected Server; there is no separate authentication switch in Hubble. The supported combinations are:

HugeGraph Server / PDDeploymentHubble compatibilityScope and limitations
Server 1.5.xStandalone, normally without authenticationMinimum compatibilityBasic graph, schema, data and Gremlin workflows only. GraphSpace, account permissions, PD/Store topology, cluster operations and newer algorithms are unavailable.
Server 1.7.x with matching PD/Store 1.7.xStandalone or distributedMinimum compatibility through legacy adaptersCore management and query workflows stay usable, but legacy REST/Gremlin authentication, permission semantics, metrics and algorithm capabilities give a reduced experience.
Server, PD and Store 1.8.x or laterDistributed deployment recommendedFull and recommended experienceGraphSpace, account permission presets, cluster operations, async tasks and algorithm capability handling are designed and validated against this generation.

Use matching Server, PD and Store minor versions in a distributed cluster.

2 Deploy

There are three ways to deploy hugegraph-hubble

  • Use Docker (Convenient for Test/Dev)
  • Download the Toolchain binary package
  • Source code compilation

Hubble runs on Java 11: the backend is compiled with java.version=11 and the Docker image is based on eclipse-temurin:11-jre. bin/start-hubble.sh only checks that a java binary is on the PATH, so make sure the right JDK is selected.

2.1 Use docker (Convenient for Test/Dev)

Special Note: Hubble no longer asks for the Server host and port on the web page. The Server address comes from conf/hugegraph-hubble.properties: server.direct_url when pd.enabled=false, or PD discovery through pd.peers when pd.enabled=true. Inside the container 127.0.0.1 refers to the hubble container itself, so the packaged default server.direct_url=http://127.0.0.1:8080 does not reach a Server running in another container.

If hubble and server are in the same docker network, we recommend using the container_name (in our example, it is server) as the hostname, and 8080 as the port. Or you can use the host IP as the hostname, and the port is configured by the host for the server.

The image copies the packaged distribution to /hubble, rewrites server.host=0.0.0.0 and clears dashboard.address in /hubble/conf/hugegraph-hubble.properties, exposes port 8088 and runs ./bin/start-hubble.sh -f in the foreground.

Prepare a hugegraph-hubble.properties that points at your Server and keeps the container listening on all interfaces:

server.host=0.0.0.0
server.port=8088
pd.enabled=false
server.direct_url=http://server:8080

Then start hubble with that file mounted over the packaged configuration:

docker run -itd --name=hubble -p 8088:8088 \
  -v "$PWD/hugegraph-hubble.properties:/hubble/conf/hugegraph-hubble.properties" \
  hugegraph/hubble:1.7.0

Alternatively, you can use Docker Compose to start hubble. Additionally, if hubble and the graph is in the same Docker network, you can access the graph using the container name of the graph, eliminating the need for the host machine’s IP address.

Use docker-compose up -d, docker-compose.yml is following:

version: '3'
services:
  server:
    image: hugegraph/hugegraph:1.7.0
    container_name: server
    environment:
      - PASSWORD=xxx
    ports:
      - 8080:8080

  hubble:
    image: hugegraph/hubble:1.7.0
    container_name: hubble
    ports:
      - 8088:8088
    volumes:
      - ./hugegraph-hubble.properties:/hubble/conf/hugegraph-hubble.properties

Note:

  1. The docker image of hugegraph-hubble is a convenience release to start hugegraph-hubble quickly, but not official distribution artifacts. You can find more details from ASF Release Distribution Policy.

  2. Recommend to use release tag (like 1.7.0) for the stable version. Use latest tag to experience the newest functions in development.

2.2 Download the Toolchain binary package

hubble is in the toolchain project. First, download the binary tar tarball

export VERSION=1.7.0
export ARCHIVE="apache-hugegraph-toolchain-incubating-${VERSION}"
wget "https://downloads.apache.org/hugegraph/${VERSION}/${ARCHIVE}.tar.gz"
tar -xvf "${ARCHIVE}.tar.gz"
cd "${ARCHIVE}/apache-hugegraph-hubble-incubating-${VERSION}"

Edit conf/hugegraph-hubble.properties so that the Server address is correct, then run hubble

bin/start-hubble.sh

start-hubble.sh accepts the following options:

OptionDescription
-f, --foreground [true|false]Run in the foreground instead of as a daemon; the Docker image uses -f
-d, --debugEnable the JDWP debugger on port 8787 (server=y,suspend=n)

The script starts the JVM with -Xms512m -Dfile.encoding=UTF-8 -Dhubble.home.path=<install dir>, writes the PID to bin/pid, logs to logs/hugegraph-hubble.log and waits up to 30 seconds for http://<server.host>:<server.port>/about to answer before it returns.

The packaged default is server.host=localhost, so the service only accepts loopback connections until you change it. After startup, open http://<host>:8088.

Run bin/stop-hubble.sh to stop the service. It sends SIGTERM first so that the shutdown hooks pause running load tasks and close the embedded H2 database cleanly, and only escalates to SIGKILL if the process is still alive after STOP_TIMEOUT seconds (environment variable, default 30).

2.3 Source code compilation

Hubble’s build uses frontend-maven-plugin in hugegraph-hubble/hubble-dist/pom.xml to install Node.js v18.20.8 and Yarn v1.22.21, so neither tool needs to be installed beforehand. JDK 11 and Maven are required.

Download the toolchain source code.

git clone https://github.com/apache/hugegraph-toolchain.git

Compile hubble. It depends on the loader and client, so you need to build these dependencies in advance during the compilation process (you can skip this step later).

cd hugegraph-toolchain
python -m pip install -r hugegraph-hubble/hubble-dist/assembly/travis/requirements.txt
mvn install -pl hugegraph-client,hugegraph-loader -am -Dmaven.javadoc.skip=true -DskipTests -ntp
cd hugegraph-hubble
mvn -e compile package -Dmaven.javadoc.skip=true -Dmaven.test.skip=true -ntp
cd apache-hugegraph-hubble-*

Run hubble

bin/start-hubble.sh -d

For frontend work, run yarn dev inside hubble-fe. The backend POM does not configure spring-boot:run, so run org.apache.hugegraph.HugeGraphHubble from hubble-be/target/classes with -Dhubble.home.path pointing at a writable directory instead.

3 Platform Workflows

The home page groups the modules into three journeys: Graph Overview, Graph Import and Graph Query. It also shows whether Hubble runs in PD / cluster mode or in non-PD standalone mode. The module usage process of the platform is as follows:

image

4 Platform Instructions

4.1 Graph Management

In PD mode, [Graph Space Management] lists all GraphSpaces of the cluster and can create or edit one, including its alias, optional Kubernetes namespace and compute task, and resource limits. In non-PD standalone mode there is exactly one GraphSpace named DEFAULT and the GraphSpace list is skipped.

4.1.1 Graph creation

Under the graph management module, click [New Graph] and fill in the graph name, an optional alias, an optional schema template and optional sample data. The graph name is unique inside its GraphSpace and cannot be changed after creation.

image

Create graph by filling in the content as follows:

image

Special Note: The Server connection is not configured on this page. It comes from conf/hugegraph-hubble.properties, through server.direct_url or PD discovery; see section 2.1 for the Docker hostname rules. Graph creation is only offered when the connected Server exposes it (REST API 0.67 or later); on older Servers the graph list is read-only.

4.1.2 Graph Access

Realize the information access to the graph space. After entering, you can perform operations such as multidimensional query analysis, metadata management, data import, and algorithm analysis of the graph. [Open Graph Studio] opens the query workbench, [Metadata Config] opens the schema pages, and the graph detail page shows vertex and edge statistics together with the schema.

image
4.1.3 Graph management
  1. The graph list has a card view and a list view. Search matches the graph name.
  2. Per-graph actions are View Schema (with [Export Groovy Schema]), Metadata Config, Clone Graph (schema only, or schema and data), Clear Schema and Data, Delete, and, in PD mode, Set Default.
  3. [Sample data and resources] builds a demo graph inside the current graph: the Red Chamber demo graph, the People & Software demo graph, or the Tiny Movie Rank demo. These demos add missing schema and elements only and never clear existing data.
image

4.2 Metadata Modeling (list + graph mode)

4.2.1 Module entry

Open [Metadata Config] from the graph list, or the metadata page of a graph at /graphspace/<graphspace>/graph/<graph>/meta. The page has five tabs, Property, Vertex Type, Edge Type, Vertex Index and Edge Index, and a switch between list view and graph view.

image
4.2.2 Property type
4.2.2.1 Create type
  1. Fill in or select the property name, data type, and cardinality to complete the creation of the property.
  2. Created properties can be used as properties of vertex type and edge type.

List mode:

image

Graph mode:

image
4.2.2.2 Management
  1. You can delete a single item or delete it in batches in the property list. A property that is still used by a vertex or edge type cannot be deleted.
  2. Deleting metadata runs as an asynchronous task; check Async Tasks for its progress.
4.2.3 Vertex type
4.2.3.1 Create type
  1. Fill in or select the vertex type name, ID strategy, associated properties, primary key properties, vertex style, content displayed below the vertex in the query result, and index information: including whether to create a type index, and the specific content of the property index, complete the vertex type creation.

List mode:

image

Graph mode:

image
4.2.3.2 Administration
  1. Editing operations are available. The vertex style, associated properties, vertex display content, and property index can be edited, and the rest cannot be edited. In graph mode, double-click a vertex type to edit it.

  2. You can delete a single item or delete it in batches.

image
4.2.4 Edge Types
4.2.4.1 Create
  1. Fill in or select the edge type name, the type (Normal, Parent or Sub, for edge type hierarchies), start point type, end point type, associated properties, whether to allow multiple connections, edge style, content displayed below the edge in the query result, and index information: including whether to create a type index, and the specific content of the property index, complete the creation of the edge type.

List mode:

image

Graph mode:

image
4.2.4.2 Administration
  1. Editing operations are available. Edge styles, associated properties, edge display content, and property indexes can be edited, and the rest cannot be edited, the same as the vertex type.
  2. You can delete a single item or delete it in batches.
4.2.5 Index Types

Displays vertex and edge indexes for vertex types and edge types. Secondary, range, search and unique indexes are supported.

4.2.6 Schema Templates

[Schema templates] at /graphspace/<graphspace>/schema keeps a reusable template library for the current GraphSpace. Example templates ship with Hubble and can be used, removed or restored; they are not stored on the Server until you save one. User templates hold Groovy schema on the Server and can be created, edited and deleted. When you create a graph, an existing template can be selected so that its schema is applied right away.

4.3 Data Import

Note: currently, we recommend to use hugegraph-loader to import data formally. The built-in import of hubble is used for testing and getting started.

The usage process of data import is as follows:

image
4.3.1 Module entrance

Left navigation, under Graph Import: [Data Sources] and [Data Import].

image
4.3.2 Data sources
  1. [Data Sources] registers where an import task reads from. Four source types are supported: FILE (local upload), HDFS, Kafka and JDBC.
  2. For a FILE source, upload the files that need to be composed. The accepted formats come from upload_file.format_list, which defaults to csv and txt.
  3. The single file and total size limits default to 1 GB and 10 GB, and unfinished uploads are discarded after upload_file.max_uploading_time, which defaults to 12 hours.
image
4.3.3 Create task
  1. [Data Import] > [Create Task] configures an import in four steps: Basic Information, Select Source Fields, Select Mapping Fields and Schedule.
  2. Basic Information takes the task name (1 to 48 Chinese characters, letters, digits or _), the target GraphSpace and graph, the source type and the data source.
  3. Multiple import tasks can be created and imported in parallel.
image
4.3.4 Setting up data mapping
  1. Set up data mapping for the selected source, including file settings and type settings

  2. File settings: check or fill in whether to include the header, separator, encoding format and other settings of the source itself, all set the default values, no need to fill in manually

  3. Type setting:

    1. Vertex map and edge map:

      【Vertex Type】: Select the vertex type, and map the column data of the source for its ID;

      【Edge Type】: Select the edge type and map the column data of the source to the ID column of its start point type and end point type;

    2. Mapping settings: map the column data of the source to the properties of the selected vertex type. Here, if the property name is the same as the header name of the file, the mapping property can be automatically matched, and there is no need to manually fill in the selection.

    3. After completing the setting, the setting list will be displayed before proceeding to the next step. It supports the operations of adding, editing and deleting mappings.

Fill in the settings map:

image

Mapping list:

image
4.3.5 Import data

The last step chooses when the task runs: Run Once for a one-off import, Scheduled with a Quartz cron expression such as 0 0/5 * * * ?, or Realtime for a Kafka source.

  1. Import settings
  • The import setting parameter items are as shown in the figure below, all set the default value, no need to fill in manually
image
  1. Import details
  • Run a task from the task list to start the import, and pause, edit or delete it from the same list
  • The execution history of a task provides the execution instance ID, the number of imported records, the average rate in records per second, the import duration and the status of each run
  • If the import fails, you can view the specific reason
image

4.4 Graph Query

4.4.1 Module entry

Left navigation, under Graph Query: [GQL Traversal].

image
4.4.2 Multi-graphs switching

The top bar carries the current GraphSpace and graph, so you can flexibly switch the operation space of multiple graphs without leaving the page.

image
4.4.3 Graph Analysis and Processing

HugeGraph supports Gremlin, a graph traversal query language of Apache TinkerPop3. Gremlin is a general graph database query language. By entering Gremlin statements and clicking execute, you can perform query and analysis operations on graph data, and create and delete vertices/edges, modify vertex/edge properties, etc. When the connected Server supports Cypher, a Cypher tab is offered next to Gremlin. A Text2GQL tab is present as a user interface preview only: it is not connected to a model or a query service, and nothing entered there is sent or executed.

Each statement can run in one of two modes. Immediate returns the result inline and suits analyses that finish within about 30 seconds; Async submits a task instead, and its progress and result appear under Async Tasks. Ctrl/Command + Enter runs the current statement.

After the query, below is the graph result display area, which provides 3 kinds of graph result display modes: [Graph Mode], [Table Mode], [Json Mode]. The graph canvas can be rendered in 2D or 3D.

⚠️ SEC Reminder: Hubble allows the direct input and execution of native Gremlin query statements on the web interface, which grants users relatively high operational privileges. Please avoid exposing the Hubble service to public network environments. It is recommended to ensure that the graph database server has enabled the Authentication System (Auth) combined with an IP Whitelist for strict permission control when in use, preventing unauthorized access or malware execution risks.

Support zoom, center, full screen, layout and style configuration, legend, minimap, undo and redo, and export operations. The canvas can be exported as JSON, CSV or an image, and a previously exported canvas can be imported again.

【Picture Mode】

image

【Table mode】

image

【Json mode】

image
4.4.4 Data Details

Click the vertex/edge entity to view the data details of the vertex/edge, including vertex/edge type, vertex ID, attribute and corresponding value, expand the information display dimension of the graph, and improve the usability.

4.4.5 Multidimensional Path Query of Graph Results

In addition to the global query, an in-depth customized query and hidden operations can be performed for the vertices in the query result to realize customized mining of graph results.

Right-click a vertex, and the menu entry of the vertex appears, which can be displayed, inquired, hidden, etc.

  • Expand: Click to display the vertices associated with the selected point.
  • Query: By selecting the edge type and edge direction associated with the selected point, and then selecting its attributes and corresponding filtering rules under this condition, a customized path display can be realized.
  • Hide: When clicked, hides the selected point and its associated edges.

Double-clicking a vertex also displays the vertex associated with the selected point.

image
4.4.6 Add vertex/edge
4.4.6.1 Added vertex

In the graph area, two entries can be used to dynamically add vertices, as follows:

  1. Click on the graph area panel, the Add Vertex entry appears
  2. Click the first icon in the action bar in the upper right corner

Complete the addition of vertices by selecting or filling in the vertex type, ID value, and attribute information.

The entry is as follows:

image

Add the vertex content as follows:

image
4.4.6.2 Add edge

Right-click a vertex in the graph result to add the outgoing or incoming edge of that point.

4.4.7 Execute the query of records and favorites
  1. Record each query record at the bottom of the graph area, including: query time, execution type, content, status, time-consuming, as well as [collection] and [load] operations, to achieve a comprehensive record of graph execution, with traces to follow, and Can quickly load and reuse execution content
  2. Provides the function of collecting sentences, which can be used to collect frequently used sentences, which is convenient for fast calling of high-frequency sentences.
image

4.5 Async Tasks

4.5.1 Module entry

Left navigation, under Graph Query: [Async Tasks].

image
4.5.2 Task Management
  1. Provide unified management and result viewing of asynchronous tasks. The task types are:
  • gremlin: Gremlin tasks
  • cypher: Cypher tasks
  • computer-dis: algorithm tasks
  • remove_schema: remove metadata
  • create_index: create an index
  • rebuild_index: rebuild the index
  • vermeer-task:load: Vermeer graph load tasks
  • vermeer-task:compute: Vermeer graph compute tasks
  1. The list displays the asynchronous task information of the current graph, including task ID, task name, task type, creation time, time-consuming, status, operation, and realizes the management of asynchronous tasks. The list refreshes every 5 seconds.
  2. Support filtering by task type and status
  3. Support searching for task ID and task name
  4. A running task can be cancelled, and asynchronous tasks can be deleted one by one or in batches
image
4.5.3 Gremlin asynchronous tasks
  1. Create a task
  • The graph query module supports two execution modes, immediate query and asynchronous task; if the user switches to the asynchronous mode, after clicking execute, an asynchronous task will be created in the asynchronous task center. A Cypher statement creates a Cypher task in the same way;
  1. Task submission
  • After the task is submitted successfully, the graph area returns the submission result and task ID
  1. Mission details
  • Provide [View] entry, you can jump to the task details to view the specific execution of the current task After jumping to the task center, the currently executing task line will be displayed directly
image

Click to view the entry to jump to the task management list, as follows:

image
  1. View the results
  • The results are displayed in the form of JSON, and a compact result can be expanded inline
4.5.4 Algorithm tasks

Batch algorithms submitted from [Built-in Graph Algorithms] land here as algorithm tasks, and so do Vermeer graph load and compute tasks. Find a task by ID in the list and open it to follow its progress and result. See section 4.6 for the algorithm forms themselves.

4.5.5 Delete metadata, rebuild index
  1. Create a task
  • In the metadata modeling module, when deleting metadata, an asynchronous task for deleting metadata can be created
image
  • When editing an existing vertex/edge type operation, when adding an index, an asynchronous task of creating an index can be created
image
  1. Task details
  • After confirming/saving, you can jump to the task center to view the details of the current task
image

4.6 Built-in Graph Algorithms

[Built-in Graph Algorithms] under Graph Query provides parameter forms for the algorithms the Server exposes, grouped by intent: explore neighborhoods, find paths and connections, compare and rank, measure importance, find communities, and analyze graph structure. Each algorithm links to its official API documentation.

Two execution modes are offered:

  • Interactive exploration runs the Server’s OLTP traverser APIs and returns results directly. It covers K-out and K-neighbor, shortest path in its single source, weighted, and multi-node forms, paths and all paths, customized and template paths, rings and rays, crosspoints and customized crosspoints, same neighbors, Jaccard similarity, fusiform similarity, Adamic-Adar, resource allocation, egonet, and the rank and neighbor rank APIs.
  • Cluster batch computation submits an asynchronous job over the whole graph and reports the result under Async Tasks. It covers PageRank and personal PageRank, degree, closeness and betweenness centrality, K-core, weakly connected components, label propagation, Louvain, triangle count, cluster coefficient, rings detection, subgraph matching and links, with Vermeer variants where the deployment provides Vermeer.

Batch algorithms need a HugeGraph Computer environment, including Kubernetes when the deployment requires it. When Computer cannot be reached, the page says so instead of submitting the task.

4.7 Sign-in and account management

When the connected Server has authentication enabled, Hubble opens the sign-in page at /login. Sign in with a HugeGraph Server account: Hubble forwards the credentials to the Server and keeps the returned token for the browser session, and it stores no accounts of its own. Login attempts are throttled, so after the first three failures for the same account and address, further attempts back off starting at 5 seconds and doubling up to 600 seconds. When the Server allows anonymous access, /login redirects to the home page and the profile and account pages are hidden.

[My Profile] shows the account details and changes the password. [Account Management] is available to accounts that may manage accounts or GraphSpace members. It creates accounts and assigns one of four access presets: Super Administrator, GraphSpace Read-only, GraphSpace Read-write and GraphSpace Administrator. Low-level role, target, access and belong records are not exposed in the interface.

4.8 Cluster operations

In PD mode, [System & Operations] adds [Cluster Overview] and [Node details] for accounts with the matching capabilities. Cluster Overview shows the topology, per-tier node status and cluster facts such as stores online, PD leader, capacity, data size, graphs, partitions and replicas. Node details lists every discovered node with filters for type and status, and opens a node profile with its metrics, leader role and Raft shards. Node details is also available in standalone mode; Cluster Overview needs PD.

An optional external dashboard can be linked from the navigation page through dashboard.address. It is a separate monitoring entry, and leaving it unconfigured does not affect Cluster Overview or Node details.

5 Configuration

HugeGraph-Hubble can be configured through the conf/hugegraph-hubble.properties file.

5.1 Service Configuration

Configuration ItemDefault ValueDescription
server.hostlocalhostThe address that Hubble binds to. The Docker image rewrites it to 0.0.0.0
server.port8088The port that Hubble listens on
server.protocolhttpProtocol used to reach HugeGraphServer, http or https
ssl.client_truststore_fileconf/hugegraph.truststoreClient truststore path, used when server.protocol=https
ssl.client_truststore_passwordhugegraphClient truststore password, used when server.protocol=https

5.2 Server and PD

ConfigurationDefaultDescription
pd.enabledfalseWhether to discover services through PD; keep false for a standalone Server
server.direct_urlhttp://127.0.0.1:8080Server address used when pd.enabled=false
pd.peers127.0.0.1:8686PD node address
pd.server127.0.0.1:8620PD service address
clusterhgName of the cluster Hubble connects to
route.typeNODE_PORTService routing mode: NODE_PORT, DDS, or BOTH
client.request_timeout60Request timeout in seconds for the HugeGraph client
client.url_cache_max_entries1024Discovered URL scopes retained for stale fallback

5.3 Gremlin Query Limits

These settings control query result limits to prevent memory issues:

Configuration ItemDefault ValueDescription
gremlin.suffix_limit250Maximum query suffix length
gremlin.vertex_degree_limit100Maximum vertex degree to display
gremlin.edges_total_limit500Maximum number of edges returned
gremlin.batch_query_ids100ID batch query size
execute-history.show_limit500Number of execution records kept for display

5.4 File Upload

These keys are not written into the packaged file; add them to override the defaults.

Configuration ItemDefault ValueDescription
upload_file.locationupload-filesDirectory that holds uploaded files
upload_file.format_listcsv,txtAccepted upload formats
upload_file.single_file_size_limit1 GBSize limit for one uploaded file
upload_file.total_file_size_limit10 GBTotal size limit for uploaded files
upload_file.max_uploading_time43200Seconds before unfinished upload parts are cleared

5.5 Cluster Operations

These keys drive the Cluster Overview and Node details pages.

Configuration ItemDefault ValueDescription
operations.connect_timeout_ms1500Connection timeout for each operations upstream
operations.read_timeout_ms2500Read timeout for each operations upstream
operations.max_response_bytes1048576Maximum accepted body size from an operations upstream
operations.cache_ttl_seconds5Lifetime of a fresh operations snapshot
operations.cache_max_entries1024Operations snapshots retained across credentials
operations.store_threads16Concurrent Store metric collection tasks
operations.store_deadline_ms5000Deadline for one Store metric collection pass
operations.store.allowed_targets[http://127.0.0.1:8520,http://[::1]:8520]Exact Store metric origins Hubble may contact
operations.pd.username / operations.pd.passwordhubble / emptyPD service identity used by the backend only
operations.store.username / operations.store.passwordhubble / emptyStore service identity used by the backend only
dashboard.address127.0.0.1:8092Optional external dashboard; empty hides the entry

The operations.store.allowed_targets default covers local testing only. A production deployment must list every trusted Store scheme, host and port explicitly, because discovery never adds an origin to this allowlist. HTTPS origins keep their configured hostname for TLS SNI and certificate verification. Supply the PD and Store passwords through a protected deployment configuration rather than the packaged file.

2.3 - Graph import

Choose an import tool when you need to write file, database, or message data into HugeGraph. Use Loader for a direct import, SeaTunnel Sink when an existing Source, Transform, and Sink pipeline should be reused, or Spark Connector from a Spark job.

2.3.1 - Import Graph Data with SeaTunnel Sink

SeaTunnel connects data sources such as databases and Kafka to HugeGraph. The connector has two parts: Source reads data and Sink writes data[1][2], with SeaTunnel transform components available between them. To export or migrate data from HugeGraph, see the SeaTunnel Source export and migration guide.

Version requirement: This guide targets SeaTunnel 3.0+. All examples use mappings

Loader imports data directly with graph mappings; SeaTunnel 3.0+ combines Source, Transform, and Sink, and both support JDBC, Kafka, and graph data

Click a diagram to view the original size.

1 Loader, Tools, and SeaTunnel

HugeGraph-Loader is suited to direct imports from common data sources. HugeGraph-Tools focuses on standalone graph management, backup, and export. SeaTunnel organizes a job as Source → Transform → Sink, so you can reuse existing connectors, transforms, and data pipelines.

Table legend

✅ Supported natively; ⚠️ conditional support or requires an extra component/external platform; ❌ not provided

ComparisonLoaderToolsSeaTunnel
Task coverage✅ Direct graph imports✅ Backup, restore, and export✅ Import, export, and migration with composable Source, Transform, and Sink stages
Job configurationJSON mapping file describing the source, vertices, and edgesCommand-line options and operationsHOCON job file[3] combining Source, Transform, and Sink
Default deployment✅ Standalone CLI; ⚠️ Spark Loader can extend it✅ Standalone CLI✅ Standalone; ✅ distributed
Execution engine⚠️ Mainly CLI; Spark Loader is a separate extension❌ Does not provide a Spark/Flink execution engine✅ HugeGraph Source and Sink support Zeta, Spark, and Flink[1][2][7][8][9][10]
Frontend and observability❌ No built-in frontend; inspect CLI logs❌ No built-in frontend; inspect CLI logs✅ Built-in Web UI job panel for task status and runtime information
Input and output⚠️ Focused on graph imports and common files, JDBC, Kafka, and similar sources⚠️ Focused on graph data and backup files in common storage✅ Dozens of connectors, including JDBC, Kafka, and SQL-CDC
Scheduling and resource management❌ No unified cross-task scheduling or resource allocation❌ No unified cross-task scheduling or resource allocation⚠️ Can integrate with DolphinScheduler for scheduling and task management
Simplicity✅ Focused and simple; a future binary CLI will make quick use easier✅ Direct commands for standalone operations⚠️ More runtime components, suited to long-lived data pipelines
High-throughput import✅ Supports bypass-server and other optimizations; measured peaks can reach 1-2 million records/s with specific backends and hardware, so benchmark the actual setup⚠️ Focuses on backup and export rather than bulk-import throughput✅ Scales throughput through parallelism, distributed engines, and connectors

SeaTunnel covers Loader’s graph-import and Tools’ export and migration scenarios in one expandable pipeline, and it also supports SQL-CDC and dozens of input and output types. Loader and Tools normally run on one machine, while SeaTunnel supports both standalone and distributed deployments and scales with data and task volume. Tools’ schedule-backup can create a crontab entry, but it does not provide unified workflow orchestration and resource management.

Existing Spark/Flink daily jobs

Both HugeGraph Source and Sink list SeaTunnel Engine (Zeta), Spark, and Flink as supported engines in SeaTunnel 3.0.0-release. If you express the daily job as a SeaTunnel job and submit it to that engine, records can move directly from Source to Transform to Sink without an intermediate file. If you keep the existing Spark/Flink DAG, SeaTunnel does not automatically take over its in-memory DataFrame or stream. Adapt it into a SeaTunnel job or expose the data through a Source connector

Loader and Tools are focused, direct, and quick to start. Use Loader for a direct graph import; use Tools for backup, restore, export, or daily operations. If a SeaTunnel job already exists, adding HugeGraph to that pipeline is usually simpler. For higher import throughput, Loader’s bypass-server path and other import optimizations are a better fit; measured peaks of 1-2 million records/s require a specific backend, data set, and hardware configuration and are not a general performance guarantee. For new SeaTunnel jobs, use 3.0+ and mappings. Recheck the connector configuration when using another version.

2 Prepare the environment

2.1 Get SeaTunnel 3.0+

The SeaTunnel 3.0+ setup guide lists JDK 8 and JDK 11 as supported. This guide uses JDK 11 and sets JAVA_HOME. Clone the SeaTunnel 3.0+[4] branch and build a distribution by following the upstream development setup guide[5]:

git clone --branch 3.0.0-release https://github.com/apache/seatunnel.git
cd seatunnel
./mvnw clean package -pl seatunnel-dist -am -Dmaven.test.skip=true

Extract the binary package from seatunnel-dist/target/. Run the remaining commands from the extracted SeaTunnel installation directory. When updating the feature set, switch to another version as needed. Keep the engine and connector plugins from the same build, and do not mix different plugin versions.

This guide uses the bundled Zeta engine in local mode[6][7]. Check that connectors/ contains HugeGraph and the JDBC or Kafka connector required by each example[11][12]. If a custom build does not include them, add the plugins produced by that same build. The JDBC examples also require the MySQL driver JAR in lib/, with driver class com.mysql.cj.jdbc.Driver.

2.2 Prepare HugeGraph and data sources

Start HugeGraph Server and create a graph for testing. The examples use the hugegraph graph in the DEFAULT graph space. Adjust these names to match the server configuration; graph space names are case-sensitive. If authentication is enabled, provide username and password in the HugeGraph Source and Sink configurations.

The following graph model is shared by the JDBC and Kafka examples. mappings creates missing PropertyKey, VertexLabel, and EdgeLabel definitions by default; existing schema definitions must be compatible.

Graph elementName and properties
Propertiesname is Text; age and since are Int
Vertexperson, primary key name, properties name and age
Edgeknows, from person to person, property since

The mysql, kafka, and hugegraph host names in the examples are placeholders. Replace them with addresses reachable from the SeaTunnel runtime. Inside a container, 127.0.0.1 points to that container; services on the same Docker network can use their service names. Set host to a host name or IP address, and set the port separately.

3 Import from a relational database (sql2graph)

Use two jobs for this import: write the person table as vertices first, then write the knows table as edges. Both edge endpoints will already exist when the edge job runs.

The person table creates marko and vadas vertices; the knows table creates a directed edge with since 2010 through endpoint fields

3.1 Import vertices

Prepare the sample data in the MySQL demo database and grant the configured account read access:

CREATE TABLE person (
  name VARCHAR(64) PRIMARY KEY,
  age INT NOT NULL
);
INSERT INTO person VALUES ('marko', 29), ('vadas', 27);

Save the following as config/sql2graph-person.conf and replace the database user name and password:

env {
  job.mode = "BATCH"
}

source {
  Jdbc {
    url = "jdbc:mysql://mysql:3306/demo?useSSL=false&serverTimezone=UTC"
    driver = "com.mysql.cj.jdbc.Driver"
    username = "seatunnel"
    password = "change_me"
    query = "SELECT name, age FROM person ORDER BY name"
  }
}

sink {
  HugeGraph {
    host = "hugegraph"
    port = 8080
    graph_name = "hugegraph"
    graph_space = "DEFAULT"
    batch_failure_fallback = false
    mappings = [
      {
        type = "VERTEX"
        label = "person"
        idStrategy = "PRIMARY_KEY"
        idFields = ["name"]
        properties = ["name", "age"]
      }
    ]
  }
}
./bin/seatunnel.sh --config ./config/sql2graph-person.conf -m local

Check the result in Hubble or Gremlin. You should find marko and vadas with their ages:

g.V().hasLabel('person').valueMap('name', 'age')

idFields = ["name"] uses the name to generate the primary key. Importing the same name again writes to the same vertex. properties lists the source fields to write.

3.2 Import edges

Prepare the relation table. Its two endpoint fields correspond to person.name from the vertex job:

CREATE TABLE knows (
  source_name VARCHAR(64) NOT NULL,
  target_name VARCHAR(64) NOT NULL,
  since INT NOT NULL
);
INSERT INTO knows VALUES ('marko', 'vadas', 2010);
Expand the configuration and save it as config/sql2graph-knows.conf
env {
  job.mode = "BATCH"
}

source {
  Jdbc {
    url = "jdbc:mysql://mysql:3306/demo?useSSL=false&serverTimezone=UTC"
    driver = "com.mysql.cj.jdbc.Driver"
    username = "seatunnel"
    password = "change_me"
    query = "SELECT source_name, target_name, since FROM knows ORDER BY source_name, target_name"
  }
}

sink {
  HugeGraph {
    host = "hugegraph"
    port = 8080
    graph_name = "hugegraph"
    graph_space = "DEFAULT"
    batch_failure_fallback = false
    check_vertex = true
    mappings = [
      {
        type = "EDGE"
        label = "knows"
        sourceConfig = {
          label = "person"
          idFields = ["source_name"]
        }
        targetConfig = {
          label = "person"
          idFields = ["target_name"]
        }
        fieldMapping = {
          source_name = "name"
          target_name = "name"
        }
        properties = ["since"]
      }
    ]
  }
}

After the vertex job succeeds, run the edge job:

./bin/seatunnel.sh --config ./config/sql2graph-knows.conf -m local

The following query should return a knows edge from marko to vadas with since set to 2010:

g.V().has('person', 'name', 'marko').outE('knows').where(inV().has('name', 'vadas')).valueMap()

sourceConfig and targetConfig identify the endpoint fields. fieldMapping maps them to the vertex primary key name, and properties = ["since"] writes only the edge property. The example enables check_vertex = true and disables per-record fallback after a batch failure (batch_failure_fallback = false), so a missing endpoint or write failure causes the job to fail.

If the relation table has only numeric foreign keys while the graph uses names as primary keys, join the names in SQL before passing the records to the Sink. See MySQL CDC Source[13] for MySQL CDC integration.

4 Import from Kafka (kafka2graph)

Kafka is useful for a continuous stream of events. Create the user-events topic and publish the following JSON message. Each message becomes one person vertex:

{"name":"marko","age":29}

Save the following as config/kafka2graph.conf:

env {
  job.mode = "STREAMING"
  checkpoint.interval = 10000
  sink.flush.interval = 5000
}

source {
  Kafka {
    bootstrap.servers = "kafka:9092"
    topic = "user-events"
    consumer.group = "hugegraph-import"
    start_mode = "earliest"
    format = "json"
    schema = {
      fields = {
        name = "string"
        age = "int"
      }
    }
  }
}

sink {
  HugeGraph {
    host = "hugegraph"
    port = 8080
    graph_name = "hugegraph"
    graph_space = "DEFAULT"
    batch_failure_fallback = false
    mappings = [
      {
        type = "VERTEX"
        label = "person"
        idStrategy = "PRIMARY_KEY"
        idFields = ["name"]
        properties = ["name", "age"]
      }
    ]
  }
}
./bin/seatunnel.sh --config ./config/kafka2graph.conf -m local

Use the Gremlin query from section 3.1 to check the data. The streaming job keeps running. checkpoint.interval saves job state every 10 seconds, while sink.flush.interval asks Zeta to flush every 5 seconds so a small number of messages does not wait for a full batch.

HugeGraph Sink writes with at-least-once semantics, so recovery can replay records. PRIMARY_KEY sends the same name to the same vertex, but it does not make every update exactly-once. Scheduled flushing is provided by Zeta and does not apply to Spark or Flink engines.

5 Common configuration and troubleshooting

The following table applies to the SeaTunnel 3.0+ version used by this guide:

ConfigurationPurpose
host, portSet the HugeGraph host and port
graph_name, graph_spaceSelect an existing graph and graph space
mappingsDefine how input fields become vertices or edges
propertiesList the source fields written by each mapping
schema_save_modemappings creates missing schema by default; existing schema must still be compatible
batch_sizeNumber of records per batch; default 500
env.sink.flush.intervalZeta scheduled flush interval in milliseconds
check_vertexCheck edge endpoints; the edge job in this guide sets it to true
batch_failure_fallback[2]Defaults to true, so a failed batch falls back to record-by-record retries, capped by max_insert_errors; the examples explicitly set false so a batch failure stops the job
max_insert_errorsNumber of failed records that record-by-record fallback may skip; default 500, -1 for unlimited, and only applies when batch_failure_fallback is enabled

Use these checks when a job fails:

  • mappings is unknown or HugeGraph Source is missing: Check that the engine and HugeGraph connector come from the same SeaTunnel 3.0+ build.
  • Connection failure: Check the host, port, graph space, authentication details, and whether the SeaTunnel runtime can reach the service.
  • Schema incompatibility: Check the ID strategy, property types, and edge endpoints. Automatic creation does not change an existing PRIMARY_KEY label into CUSTOMIZE_STRING.
  • Small Kafka batches do not appear promptly: Confirm that the job uses Zeta and set sink.flush.interval in env. In this version, batch_interval_ms is retained only for compatibility and cannot replace it.

6 Choosing a tool

Choose a tool based on the work to complete. Use Tools for graph management, Gremlin, backup, or cloning. Use Loader for a direct graph import. Choose SeaTunnel when you need to reuse a Source, Transform, and Sink pipeline. For SeaTunnel graph reads and migrations, prepare the environment using the SeaTunnel 3.0+ version used by this guide.

Choosing a tool: Tools for graph management, Loader for direct imports, and SeaTunnel for reusable data pipelines

7 References

HugeGraph connectors

[1] HugeGraph Source
[2] HugeGraph Sink

Configuration and deployment

[3] HOCON job configuration
[4] SeaTunnel 3.0.0-release branch
[5] SeaTunnel development setup
[6] SeaTunnel local deployment

Execution engines

[7] SeaTunnel Engine Overview
[8] SeaTunnel Spark Engine
[9] SeaTunnel Flink Engine
[10] Connector V2 multi-engine support

Data source connectors

[11] JDBC Source
[12] Kafka Source
[13] MySQL CDC Source

Legacy compatibility

[14] SeaTunnel 2.3.13 HugeGraph Sink

Legacy version note

This guide targets SeaTunnel 3.0+. Its Source, mappings, and graph migration examples do not apply to 2.3.13. That legacy version provides only the HugeGraph Sink, uses schema_config, and requires the graph schema to be created in advance. If you must use 2.3.13, follow the official Sink documentation[14] instead of copying this guide’s configuration

2.4 - HugeGraph-Loader Quick Start

1 HugeGraph-Loader Overview

HugeGraph-Loader is the data import component of HugeGraph, which can convert data from various data sources into graph vertices and edges and import them into the graph database in batches.

Currently supported data sources include:

  • Local disk file or directory, supports TEXT, CSV and JSON format files, supports compressed files
  • HDFS file or directory supports compressed files
  • Mainstream relational databases, such as MySQL, PostgreSQL, Oracle, SQL Server
  • Kafka topic
  • An existing HugeGraph graph, used to copy data from one graph into another

Local disk files and HDFS files support resumable uploads.

It will be explained in detail below.

Note: HugeGraph-Loader requires HugeGraph Server service, please refer to HugeGraph-Server Quick Start to download and start Server

Testing Guide: For running HugeGraph-Loader tests locally, please refer to HugeGraph Toolchain Local Testing Guide

2 Get HugeGraph-Loader

HugeGraph-Loader is available in the following three ways:

  • Use docker image (Convenient for Test/Dev)
  • Download the compiled tarball
  • Clone source code then compile and install

2.1 Use Docker image (Convenient for Test/Dev)

We can deploy the loader service using docker run -itd --name loader hugegraph/loader:1.7.0. For the data that needs to be loaded, it can be copied into the loader container either by mounting -v /path/to/data/file:/loader/file or by using docker cp.

Alternatively, to start the loader using docker-compose, the command is docker-compose up -d. An example of the docker-compose.yml is as follows:

version: '3'

services:
  server:
    image: hugegraph/hugegraph:1.7.0
    container_name: server
    ports:
      - 8080:8080

  hubble:
    image: hugegraph/hubble:1.7.0
    container_name: hubble
    ports:
      - 8088:8088

  loader:
    image: hugegraph/loader:1.7.0
    container_name: loader
    # mount your own data here
    # volumes:
      # - /path/to/data/file:/loader/file

The specific data loading process can be referenced under 4.5 User Docker to load data

Note:

  1. The docker image of hugegraph-loader is a convenience release to start hugegraph-loader quickly, but not official distribution artifacts. You can find more details from ASF Release Distribution Policy.

  2. Recommend to use release tag(like 1.7.0) for the stable version. Use latest tag to experience the newest functions in development.

2.2 Download the compiled archive

Download the latest version of the HugeGraph-Toolchain release package:

export VERSION=1.7.0
export ARCHIVE="apache-hugegraph-toolchain-incubating-${VERSION}"
wget "https://downloads.apache.org/hugegraph/${VERSION}/${ARCHIVE}.tar.gz"
tar zxf "${ARCHIVE}.tar.gz"

2.3 Clone source code to compile and install

Clone the latest version of HugeGraph-Loader source package:

# 1. get from github
git clone https://github.com/apache/hugegraph-toolchain.git

# 2. Download a released source package
export VERSION=1.7.0
export ARCHIVE="apache-hugegraph-toolchain-incubating-${VERSION}"
wget "https://downloads.apache.org/hugegraph/${VERSION}/${ARCHIVE}-src.tar.gz"
How to install OJDBC

Due to the license limitation of the Oracle OJDBC, you need to manually install ojdbc to the local maven repository. Visit the Oracle jdbc downloads page. Select Oracle Database 12c Release 2 (12.2.0.1) drivers, as shown in the following figure.

After opening the link, select “ojdbc8.jar”.

Install ojdbc8 to the local maven repository, enter the directory where ojdbc8.jar is located, and execute the following command.

mvn install:install-file -Dfile=./ojdbc8.jar -DgroupId=com.oracle -DartifactId=ojdbc8 -Dversion=12.2.0.1 -Dpackaging=jar

Compile and generate tar package:

cd hugegraph-toolchain
mvn clean package -pl hugegraph-loader -am -DskipTests -ntp

3 How to use

The basic process of using HugeGraph-Loader is divided into the following steps:

  • Write graph schema
  • Prepare data files
  • Write input source map files
  • Execute command import

3.1 Construct graph schema

This step is the modeling process. Users need to have a clear idea of ​​their existing data and the graph model they want to create, and then write the schema to build the graph model.

For example, if you want to create a graph with two types of vertices and two types of edges, the vertices are “people” and “software”, the edges are “people know people” and “people create software”, and these vertices and edges have some attributes, For example, the vertex “person” has: “name”, “age” and other attributes, “Software” includes: “name”, “sale price” and other attributes; side “knowledge” includes: “date” attribute and so on.

Example graph with person and software vertices connected by knows and created edges

graph model example

After designing the graph model, we can use groovy to write the definition of schema and save it to a file, here named schema.groovy.

// Create some properties
schema.propertyKey("name").asText().ifNotExist().create();
schema.propertyKey("age").asInt().ifNotExist().create();
schema.propertyKey("city").asText().ifNotExist().create();
schema.propertyKey("date").asText().ifNotExist().create();
schema.propertyKey("price").asDouble().ifNotExist().create();

// Create the person vertex type, which has three attributes: name, age, city, and the primary key is name
schema.vertexLabel("person").properties("name", "age", "city").primaryKeys("name").ifNotExist().create();
// Create a software vertex type, which has two properties: name, price, the primary key is name
schema.vertexLabel("software").properties("name", "price").primaryKeys("name").ifNotExist().create();

// Create the knows edge type, which goes from person to person
schema.edgeLabel("knows").sourceLabel("person").targetLabel("person").ifNotExist().create();
// Create the created edge type, which points from person to software
schema.edgeLabel("created").sourceLabel("person").targetLabel("software").ifNotExist().create();

Please refer to the corresponding section in hugegraph-client for the detailed description of the schema.

3.2 Prepare data

The data sources currently supported by HugeGraph-Loader include:

  • local disk file or directory
  • HDFS file or directory
  • Partial relational database
  • Kafka topic
  • An existing HugeGraph graph
3.2.1 Data source structure
3.2.1.1 Local disk file or directory

The user can specify a local disk file as the data source. If the data is scattered in multiple files, a certain directory is also supported as the data source, but multiple directories are not supported as the data source for the time being.

For example, my data is scattered in multiple files, part-0, part-1 … part-n. To perform the import, it must be ensured that they are placed in one directory. Then in the loader’s mapping file, specify path as the directory.

Supported file formats include:

  • TEXT
  • CSV
  • JSON

TEXT is a text file with custom delimiters, the first line is usually the header, and the name of each column is recorded, and no header line is allowed (specified in the mapping file). Each remaining row represents a record, which will be converted into a vertex/edge; each column of the row corresponds to a field, which will be converted into the id, label or attribute of the vertex/edge;

An example is as follows:

id|name|lang|price|ISBN
1|lop|java|328|ISBN978-7-107-18618-5
2|ripple|java|199|ISBN978-7-100-13678-5

CSV is a TEXT file with commas , as delimiters. When a column value itself contains a comma, the column value needs to be enclosed in double quotes, for example:

marko,29,Beijing
"li,nary",26,"Wu,han"

The JSON file requires that each line is a JSON string, and the format of each line needs to be consistent.

{"source_name": "marko", "target_name": "vadas", "date": "20160110", "weight": 0.5}
{"source_name": "marko", "target_name": "josh", "date": "20130220", "weight": 1.0}
3.2.1.2 HDFS file or directory

Users can also specify HDFS files or directories as data sources, all of the above requirements for local disk files or directories apply here. In addition, since HDFS usually stores compressed files, loader also provides support for compressed files, and local disk file or directory also supports compressed files.

Currently supported compressed file types include: GZIP, BZ2, XZ, LZMA, SNAPPY_RAW, SNAPPY_FRAMED, Z, DEFLATE, LZ4_BLOCK, LZ4_FRAMED, ORC, and PARQUET.

3.2.1.3 Mainstream relational database

The loader also supports some relational databases as data sources, and currently supports MySQL, PostgreSQL, Oracle, and SQL Server.

However, the requirements for the table structure are relatively strict at present. If association query needs to be done during the import process, such a table structure is not allowed. The associated query means: after reading a row of the table, it is found that the value of a certain column cannot be used directly (such as a foreign key), and you need to do another query to determine the true value of the column.

For example, Suppose there are three tables, person, software and created

// person schema
id | name | age | city
// software schema
id | name | lang | price
// created schema
id | p_id | s_id | date

If the id strategy of person or software is specified as PRIMARY_KEY when modeling (schema), choose name as the primary key (note: this is the concept of vertex-label in hugegraph), when importing edge data, the source vertex and target need to be spliced ​​out. For the id of the vertex, you must go to the person/software table with p_id/s_id to find the corresponding name. In the case of the schema that requires additional query, the loader does not support it temporarily. In this case, the following two methods can be used instead:

  1. The id strategy of person and software is still specified as PRIMARY_KEY, but the id column of the person table and software table is used as the primary key attribute of the vertex, so that the id can be generated by directly splicing p_id and s_id with the label of the vertex when importing an edge;
  2. Specify the id policy of person and software as CUSTOMIZE, and then directly use the id column of the person table and the software table as the vertex id, so that p_id and s_id can be used directly when importing edges;

The key point is to make the edge use p_id and s_id directly, don’t check it again.

3.2.2 Prepare vertex and edge data
3.2.2.1 Vertex Data

The vertex data file consists of data line by line. Generally, each line is used as a vertex, and each column is used as a vertex attribute. The following description uses CSV format as an example.

  • person vertex data (the data itself does not contain a header)
Tom,48,Beijing
Jerry,36,Shanghai
  • software vertex data (the data itself contains the header)
name,price
Photoshop,999
Office,388
3.2.2.2 Edge data

The edge data file consists of data line by line. Generally, each line is used as an edge. Some columns are used as the IDs of the source and target vertices, and other columns are used as edge attributes. The following uses JSON format as an example.

  • knows edge data
{"source_name": "Tom", "target_name": "Jerry", "date": "2008-12-12"}
  • created edge data
{"source_name": "Tom", "target_name": "Photoshop"}
{"source_name": "Tom", "target_name": "Office"}
{"source_name": "Jerry", "target_name": "Office"}

3.3 Write data source mapping file

3.3.1 Mapping file overview

The mapping file of the input source is used to describe how to establish the mapping relationship between the input source data and the vertex type/edge type of the graph. It is organized in JSON format and consists of multiple mapping blocks, each of which is responsible for mapping an input source. Mapped to vertices and edges.

Specifically, each mapping block contains an input source and multiple vertex mapping and edge mapping blocks, and the input source block corresponds to the local disk file or directory, HDFS file or directory and relational database are responsible for describing the basic information of the data source, such as where the data is, what format, what is the delimiter, etc. The vertex map/edge map is bound to the input source, which columns of the input source can be selected, which columns are used as ids, which columns are used as attributes, and what attributes are mapped to each column, the values ​​of the columns are mapped to what values ​​of attributes, and so on.

In the simplest terms, each mapping block describes: where is the file to be imported, which type of vertices/edges each line of the file is to be used as which columns of the file need to be imported, and the corresponding vertices/edges of these columns. what properties, etc.

Note: The format of the mapping file before version 0.11.0 and the format after 0.11.0 has changed greatly. For the convenience of expression, the mapping file (format) before 0.11.0 is called version 1.0, and the version after 0.11.0 is version 2.0. And unless otherwise specified, the “map file” refers to version 2.0.

Click to expand/collapse the skeleton of the map file for version 2.0
{
  "version": "2.0",
  "structs": [
    {
      "id": "1",
      "input": {
      },
      "vertices": [
        {},
        {}
      ],
      "edges": [
        {},
        {}
      ]
    }
  ]
}

Two versions of the mapping file are given directly here (the above graph model and data file are described)

Click to expand/collapse the mapping file for version 2.0
{
  "version": "2.0",
  "structs": [
    {
      "id": "1",
      "skip": false,
      "input": {
        "type": "FILE",
        "path": "vertex_person.csv",
        "file_filter": {
          "extensions": [
            "*"
          ]
        },
        "format": "CSV",
        "delimiter": ",",
        "date_format": "yyyy-MM-dd HH:mm:ss",
        "time_zone": "GMT+8",
        "skipped_line": {
          "regex": "(^#|^//).*|"
        },
        "compression": "NONE",
        "header": [
          "name",
          "age",
          "city"
        ],
        "charset": "UTF-8",
        "list_format": {
          "start_symbol": "[",
          "elem_delimiter": "|",
          "end_symbol": "]"
        }
      },
      "vertices": [
        {
          "label": "person",
          "skip": false,
          "id": null,
          "unfold": false,
          "field_mapping": {},
          "value_mapping": {},
          "selected": [],
          "ignored": [],
          "null_values": [
            ""
          ],
          "update_strategies": {}
        }
      ],
      "edges": []
    },
    {
      "id": "2",
      "skip": false,
      "input": {
        "type": "FILE",
        "path": "vertex_software.csv",
        "file_filter": {
          "extensions": [
            "*"
          ]
        },
        "format": "CSV",
        "delimiter": ",",
        "date_format": "yyyy-MM-dd HH:mm:ss",
        "time_zone": "GMT+8",
        "skipped_line": {
          "regex": "(^#|^//).*|"
        },
        "compression": "NONE",
        "header": null,
        "charset": "UTF-8",
        "list_format": {
          "start_symbol": "",
          "elem_delimiter": ",",
          "end_symbol": ""
        }
      },
      "vertices": [
        {
          "label": "software",
          "skip": false,
          "id": null,
          "unfold": false,
          "field_mapping": {},
          "value_mapping": {},
          "selected": [],
          "ignored": [],
          "null_values": [
            ""
          ],
          "update_strategies": {}
        }
      ],
      "edges": []
    },
    {
      "id": "3",
      "skip": false,
      "input": {
        "type": "FILE",
        "path": "edge_knows.json",
        "file_filter": {
          "extensions": [
            "*"
          ]
        },
        "format": "JSON",
        "delimiter": null,
        "date_format": "yyyy-MM-dd HH:mm:ss",
        "time_zone": "GMT+8",
        "skipped_line": {
          "regex": "(^#|^//).*|"
        },
        "compression": "NONE",
        "header": null,
        "charset": "UTF-8",
        "list_format": null
      },
      "vertices": [],
      "edges": [
        {
          "label": "knows",
          "skip": false,
          "source": [
            "source_name"
          ],
          "unfold_source": false,
          "target": [
            "target_name"
          ],
          "unfold_target": false,
          "field_mapping": {
            "source_name": "name",
            "target_name": "name"
          },
          "value_mapping": {},
          "selected": [],
          "ignored": [],
          "null_values": [
            ""
          ],
          "update_strategies": {}
        }
      ]
    },
    {
      "id": "4",
      "skip": false,
      "input": {
        "type": "FILE",
        "path": "edge_created.json",
        "file_filter": {
          "extensions": [
            "*"
          ]
        },
        "format": "JSON",
        "delimiter": null,
        "date_format": "yyyy-MM-dd HH:mm:ss",
        "time_zone": "GMT+8",
        "skipped_line": {
          "regex": "(^#|^//).*|"
        },
        "compression": "NONE",
        "header": null,
        "charset": "UTF-8",
        "list_format": null
      },
      "vertices": [],
      "edges": [
        {
          "label": "created",
          "skip": false,
          "source": [
            "source_name"
          ],
          "unfold_source": false,
          "target": [
            "target_name"
          ],
          "unfold_target": false,
          "field_mapping": {
            "source_name": "name",
            "target_name": "name"
          },
          "value_mapping": {},
          "selected": [],
          "ignored": [],
          "null_values": [
            ""
          ],
          "update_strategies": {}
        }
      ]
    }
  ]
}

Click to expand/collapse the mapping file for version 1.0
{
  "vertices": [
    {
      "label": "person",
      "input": {
        "type": "file",
        "path": "vertex_person.csv",
        "format": "CSV",
        "header": ["name", "age", "city"],
        "charset": "UTF-8"
      }
    },
    {
      "label": "software",
      "input": {
        "type": "file",
        "path": "vertex_software.csv",
        "format": "CSV"
      }
    }
  ],
  "edges": [
    {
      "label": "knows",
      "source": ["source_name"],
      "target": ["target_name"],
      "input": {
        "type": "file",
        "path": "edge_knows.json",
        "format": "JSON"
      },
      "field_mapping": {
        "source_name": "name",
        "target_name": "name"
      }
    },
    {
      "label": "created",
      "source": ["source_name"],
      "target": ["target_name"],
      "input": {
        "type": "file",
        "path": "edge_created.json",
        "format": "JSON"
      },
      "field_mapping": {
        "source_name": "name",
        "target_name": "name"
      }
    }
  ]
}

The 1.0 version of the mapping file is centered on the vertex and edge, and sets the input source; while the 2.0 version is centered on the input source, and sets the vertex and edge mapping. Some input sources (such as a file) can generate both vertices and edges. If you write in the 1.0 format, you need to write an input block in each of the vertex and edge mapping blocks. The two input blocks are exactly the same; and the 2.0 version only needs to write input once. Therefore, compared with version 1.0, version 2.0 can save some repetitive writing of input.

In the bin directory of hugegraph-loader-{version}, there is a script tool mapping-convert.sh that can directly convert the mapping file of version 1.0 to version 2.0. The usage is as follows:

bin/mapping-convert.sh struct.json

A struct-v2.json will be generated in the same directory as struct.json.

The bin directory also ships utf8-bom-to-utf8.sh, which strips the UTF-8 BOM from a single data file, or from every file under a directory. It is useful when a CSV or TEXT file exported by a Windows tool fails to parse because its first header column carries an invisible BOM:

bin/utf8-bom-to-utf8.sh /path/to/file-or-dir
3.3.2 Input Source

Input sources are currently divided into five categories: FILE, HDFS, JDBC, KAFKA and GRAPH, which are distinguished by the type node. We call them local file input sources, HDFS input sources, JDBC input sources, KAFKA input sources and GRAPH input source, which are described below.

3.3.2.1 Local file input source
  • id: The id of the input source. This field is used to support some internal functions. It is not required (it will be automatically generated if it is not filled in). It is strongly recommended to write it, which is very helpful for debugging;
  • skip: whether to skip the input source, because the JSON file cannot add comments, if you do not want to import an input source during a certain import, but do not want to delete the configuration of the input source, you can set it to true to skip it, the default is false, not required;
  • input: input source map block, composite structure
    • type: an input source type, file or FILE must be filled;
    • path: the path of the local file or directory, the absolute path or the relative path relative to the mapping file, it is recommended to use the absolute path, required;
    • file_filter: filter files with compound conditions from path, compound structure, currently only supports configuration extensions, represented by child node extensions, the default is “*”, which means to keep all files;
    • format: the format of the local file, the optional values are CSV, TEXT and JSON, which must be uppercase, the default is CSV, optional;
    • header: the column name of each column of the file, if not specified, the first line of the data file will be used as the header; when the file itself has a header and the header is specified, the first line of the file will be treated as a normal data line; JSON The file does not need to specify a header, optional;
    • has_header: for CSV and TEXT, the first line of every file is dropped when it is identical to the header, so a header repeated in each part file of a directory is not imported as data. Set this to false to turn that check off when the first line of a file is real data that happens to equal the header, optional;
    • delimiter: The column delimiter of the file line. The default depends on format: a comma "," for CSV and a tab "\t" for TEXT; a CSV file accepts no other delimiter. The JSON file does not need to be specified, optional;
    • charset: the encoded character set of the file, the default is UTF-8, optional;
    • date_format: custom date format, the default value is yyyy-MM-dd HH:mm:ss, optional; if the date is presented in the form of a timestamp, this item must be written as timestamp (fixed writing);
    • extra_date_formats: a list of fallback date formats, tried when a value does not match date_format, empty by default, optional;
    • time_zone: Set which time zone the date data is in, the default value is GMT+8, optional;
    • skipped_line: The line to be skipped, compound structure, currently only the regular expression of the line to be skipped can be configured, described by the child node regex. The default regex is (^#|^//).*|, which skips lines starting with # or // and empty lines; to keep such lines, set regex to a pattern that matches nothing, optional;
    • compression: The compression format of the file, the optional values ​​are NONE, GZIP, BZ2, XZ, LZMA, SNAPPY_RAW, SNAPPY_FRAMED, Z, DEFLATE, LZ4_BLOCK, LZ4_FRAMED, ORC and PARQUET, the default is NONE, which means a non-compressed file, optional; for ORC and PARQUET the header is matched case-insensitively;
    • list_format: When a column of the file (non-JSON) is a collection structure (the Cardinality of the PropertyKey in the corresponding figure is Set or List), you can use this item to set the start character, separator, and end character of the column, compound structure :
      • start_symbol: The start character of the collection structure column (the default value is the empty string "", JSON format currently does not support specification)
      • elem_delimiter: the delimiter of the collection structure column (the default value is |, and it must differ from delimiter; JSON format currently only supports native , delimiter)
      • end_symbol: the end character of the collection structure column (the default value is the empty string "", the JSON format does not currently support specification)
      • ignored_elems: the elements dropped after the column is split, the default value is [""], so empty elements are ignored
3.3.2.2 HDFS input source

The nodes and meanings of the above local file input source are basically applicable here. Only the different and unique nodes of the HDFS input source are listed below.

  • type: input source type, must fill in hdfs or HDFS, required;
  • path: the path of the HDFS file or directory, it must be the absolute path of HDFS, required;
  • core_site_path: the path of the core-site.xml file of the HDFS cluster, the key point is to specify the address of the NameNode (fs.default.name) and the implementation of the file system (fs.hdfs.impl), required;
  • hdfs_site_path: the path of the hdfs-site.xml file of the HDFS cluster, optional;
  • dir_filter: when path is a directory, decides which sub-directories are walked into, compound structure, optional:
    • include_regex: only directories whose name matches this regular expression are read, empty by default, which places no restriction;
    • exclude_regex: directories whose name matches this regular expression are skipped, empty by default;
  • kerberos_config: how to authenticate against a Kerberos-secured HDFS cluster, compound structure, optional:
    • enable: whether to authenticate with Kerberos, the default is false;
    • krb5_conf: the path of the krb5.conf file, required when enable is true;
    • principal: the Kerberos principal, required when enable is true;
    • keytab: the path of the keytab file, required when enable is true;
3.3.2.3 JDBC input source

As mentioned above, it supports multiple relational databases, but because their mapping structures are very similar, they are collectively referred to as JDBC input sources, and then use the vendor node to distinguish different databases.

  • type: input source type, must fill in jdbc or JDBC, required;
  • vendor: database type, optional options are [MySQL, PostgreSQL, Oracle, SQLServer], case-insensitive, required;
  • driver: the JDBC driver class, optional; when it is left out, the default driver of the vendor listed in the tables below is used;
  • url: the url of the database that jdbc wants to connect to, required;
  • database: the name of the database to be connected, required;
  • schema: The name of the schema to be connected, different databases have different requirements, and the details are explained below;
  • table: the name of the table to be connected, at least one of table or custom_sql is required;
  • custom_sql: custom SQL statement, at least one of table or custom_sql is required;
  • username: username to connect to the database, required;
  • password: password for connecting to the database, required;
  • where: an extra condition appended to the generated select statement, written without the where keyword, optional;
  • batch_size: The size of one page when obtaining table data by page, the default is 500, optional;

MYSQL

NodeFixed value or common value
vendorMYSQL
drivercom.mysql.cj.jdbc.Driver
urljdbc:mysql://127.0.0.1:3306

schema: nullable, if filled in, it must be the same as the value of database

POSTGRESQL

NodeFixed value or common value
vendorPOSTGRESQL
driverorg.postgresql.Driver
urljdbc:postgresql://127.0.0.1:5432

schema: nullable, default is “public”

ORACLE

NodeFixed value or common value
vendorORACLE
driveroracle.jdbc.driver.OracleDriver
urljdbc:oracle:thin:@127.0.0.1:1521

schema: nullable, the default value is the username in upper case

SQLSERVER

NodeFixed value or common value
vendorSQLSERVER
drivercom.microsoft.sqlserver.jdbc.SQLServerDriver
urljdbc:sqlserver://127.0.0.1:1433

schema: required

3.3.2.4 Kafka input source
  • type: input source type, kafka or KAFKA, required;
  • bootstrap_server: the list of kafka bootstrap servers, required;
  • topic: the topic to subscribe to, required;
  • group: group of Kafka consumers, required;
  • from_beginning: whether to start from the earliest offset of the topic (auto.offset.reset=earliest) instead of the latest one, default is false, optional;
  • format: format of each message, options are CSV, TEXT and JSON, must be uppercase, required;
  • header: column name of each column of a message; no header line is read from the topic, so it has to be given for CSV and TEXT, while JSON messages do not need it;
  • delimiter: delimiter of the message columns, used by TEXT only, since CSV always splits on ,, optional;
  • charset: encoding charset of the messages, default is UTF-8, optional;
  • date_format: customized date format, default value is yyyy-MM-dd HH:mm:ss, optional; if the date is presented in the form of timestamp, this item must be written as timestamp (fixed);
  • extra_date_formats: a customized list of another date formats, empty by default, optional; each item in the list is an alternate date format to the date_format specified date format;
  • time_zone: set which time zone the date data is in, default is GMT+8, optional;
  • skipped_line: the line you want to skip, composite structure, currently can only configure the regular expression of the line to be skipped, described by the child node regex, the default is not to skip any line, optional;
  • batch_size: the maximum number of records fetched in one poll (max.poll.records), default is 500, optional;
  • early_stop: the record pulled from Kafka broker at a certain time is empty, stop the task, default is false, only for debugging, optional;
3.3.2.5 GRAPH input Source

The GRAPH input source reads vertices and edges out of another HugeGraph graph, reached through HugeGraph-PD, and writes them into the target graph. When a mapping file contains a GRAPH input source, every input source in it that is not skipped has to be a GRAPH input source as well, and the loader puts the target graph into RESTORING mode for the duration of the import.

  • type: Data source type; must be filled in as graph or GRAPH (required);
  • graphspace: Source graphSpace name (required);
  • graph: Source graph name (required);
  • username: HugeGraph username; the --username command-line option is used when this is empty;
  • password: HugeGraph password; the --password command-line option is used when this is empty;
  • selected_vertices: the vertex labels to copy, each item written as {"label": "...", "properties": [...], "query": {...}}, where properties narrows the copied properties and query is an optional filter passed to the source graph;
  • ignored_vertices: the vertex labels to skip, each item written as {"label": "...", "properties": [...]};
  • selected_edges: the edge labels to copy, items have the same shape as in selected_vertices;
  • ignored_edges: the edge labels to skip, items have the same shape as in ignored_vertices;
  • pd-peers: HugeGraph-PD node addresses of the source cluster; the --pd-peers option is used when this is empty;
  • meta-endpoints: Meta service endpoints of the source cluster; the --meta-endpoints option is used when this is empty;
  • cluster: Source cluster name; the --cluster option is used when this is empty;
  • batch_size: Batch size for reading data from the source graph; default is 500;
3.3.3 Vertex and Edge Mapping

The nodes of vertex and edge mapping (a key in the JSON file) have a lot of the same parts. The same parts are introduced first, and then the unique nodes of vertex map and edge map are introduced respectively.

Nodes of the same section

  • label: label to which the vertex/edge data to be imported belongs, required;
  • skip: whether to skip this vertex/edge mapping while the input source and the other mappings stay active, the default is false, optional;
  • field_mapping: Map the column name of the input source column to the attribute name of the vertex/edge, optional;
  • value_mapping: map the data value of the input source to the attribute value of the vertex/edge, optional;
  • selected: select some columns to insert, other unselected ones are not inserted, cannot exist at the same time as ignored, optional;
  • ignored: ignore some columns so that they do not participate in insertion, cannot exist at the same time as selected, optional;
  • null_values: You can specify some strings to represent null values, such as “NULL”. If the vertex/edge attribute corresponding to this column is also a nullable attribute, the value of this attribute will not be set when constructing the vertex/edge, optional ;
  • update_strategies: If the data needs to be updated in batches in a specific way, you can specify a specific update strategy for each attribute (see below for details), optional;
  • unfold: Whether to unfold the column, each unfolded column will form a row with other columns, which is equivalent to unfolding into multiple rows; for example, the value of a certain column (id column) of the file is [1,2,3], The values ​​of other columns are 18,Beijing. When unfold is set, this row will become 3 rows, namely: 1,18,Beijing, 2,18,Beijing and 3,18, Beijing. Note that this will only expand the column selected as id. Default false, optional;

Update strategy supports 8 types: (requires all uppercase)

  1. Value accumulation: SUM
  2. Take the greater of the two numbers/dates: BIGGER
  3. Take the smaller of two numbers/dates: SMALLER
  4. Set property takes union: UNION
  5. Set attribute intersection: INTERSECTION
  6. List attribute append element: APPEND
  7. List/Set attribute delete element: ELIMINATE
  8. Override an existing property: OVERRIDE

Note: If the newly imported attribute value is empty, the existing old data will be used instead of the empty value. For the effect, please refer to the following example

// The update strategy is specified in the JSON file as follows
{
  "vertices": [
    {
      "label": "person",
      "update_strategies": {
        "age": "SMALLER",
        "set": "UNION"
      },
      "input": {
        "type": "file",
        "path": "vertex_person.txt",
        "format": "TEXT",
        "header": ["name", "age", "set"]
      }
    }
  ]
}

// 1. Write a line of data with the OVERRIDE update strategy (null means empty here)
'a b null null'

// 2. Write another line
'null null c d'

// 3. Finally we can get
'a b c d'   

// If there is no update strategy, you will get
'null null c d'

Note : After adopting the batch update strategy, the number of disk read requests will increase significantly, and the import speed will be several times slower than that of pure write coverage (at this time HDD disk [IOPS](https://en.wikipedia .org/wiki/IOPS) will be the bottleneck, SSD is recommended for speed)

Unique Nodes for Vertex Maps

  • id: Specify a column as the id column of the vertex. When the vertex id policy is CUSTOMIZE, it is required; when the id policy is PRIMARY_KEY, it must be empty;

Unique Nodes for Edge Maps

  • source: Select certain columns of the input source as the id column of source vertex. When the id policy of the source vertex is CUSTOMIZE, a certain column must be specified as the id column of the vertex; when the id policy of the source vertex is When PRIMARY_KEY, one or more columns must be specified for splicing the id of the generated vertex, that is, no matter which id strategy is used, this item is required;
  • target: Specify certain columns as the id columns of target vertex, similar to source, so I won’t repeat them;
  • unfold_source: Whether to unfold the source column of the file, the effect is similar to that in the vertex map, and will not be repeated;
  • unfold_target: Whether to unfold the target column of the file, the effect is similar to that in the vertex mapping, and will not be repeated;

3.4 Execute command import

After preparing the graph model, data file, and input source mapping relationship file, the data file can be imported into the graph database.

The import process is controlled by commands submitted by the user, and the user can control the specific process of execution through different parameters.

3.4.1 Parameter description
ParameterDefault valueRequired or notDescription
-f or --fileYPath to configure script
-g or --graphhugegraphGraph name
--graphspaceDEFAULTGraph space name
-s or --schemaSchema file path; optional when the Schema already exists
-h or --host or -ilocalhostAddress of HugeGraphServer
-p or --port8080Port number of HugeGraphServer
--usernamenullWhen HugeGraphServer enables permission authentication, the username of the current graph
--passwordnullWhen HugeGraphServer enables permission authentication, the password of the current graph
--create-graphfalseWhether to automatically create the graph if it does not exist
--tokennullWhen HugeGraphServer has enabled authorization authentication, the token of the current graph
--protocolhttpProtocol for sending requests to the server, optional http or https
--pd-peersPD service node addresses
--pd-tokenToken for accessing PD service
--meta-endpointsMeta information storage service addresses
--directfalseWhether to directly connect to HugeGraph-Store
--route-typeNODE_PORTRoute selection method (optional values: NODE_PORT / DDS / BOTH)
--clusterhgCluster name
--trust-store-fileWhen the request protocol is https, the client’s certificate file path
--trust-store-passwordWhen the request protocol is https, the client certificate password
--clear-all-datafalseWhether to clear the original data on the server before importing data
--clear-timeout240Timeout for clearing the original data on the server before importing data
--incremental-modefalseWhether to use the breakpoint resume mode; only input sources FILE and HDFS support this mode. Enabling this mode allows starting the import from where the last import stopped
--failure-modefalseWhen failure mode is true, previously failed data will be imported. Generally, the failed data file needs to be manually corrected and edited before re-importing
--batch-insert-threadsCPUsBatch insert thread pool size (CPUs is the number of logical cores available to the current OS)
--single-insert-threads8Size of single insert thread pool
--max-conn4 * CPUsThe maximum number of HTTP connections between HugeClient and HugeGraphServer; while it is left at its default, it is raised automatically to 4 * --batch-insert-threads
--max-conn-per-route2 * CPUsThe maximum number of HTTP connections for each route between HugeClient and HugeGraphServer; while it is left at its default, it is raised automatically to 2 * --batch-insert-threads
--batch-size500The number of data items in each batch when importing data
--max-parse-errors1The maximum number of data parsing errors allowed (per line); the program exits when this value is reached
--max-insert-errors500The maximum number of data insertion errors allowed (per row); the program exits when this value is reached
--timeout60Timeout (seconds) for insert result return
--shutdown-timeout10Waiting time for multithreading to stop (seconds)
--retry-times3Maximum number of retries after a timeout
--retry-interval10Interval before retry (seconds)
--check-vertexfalseWhether to check if the vertices connected by the edge exist when inserting the edge
--print-progresstrueWhether to print the number of imported items in real time on the console
--dry-runfalseEnable this mode to only parse data without importing; usually used for testing
--help or -helpfalsePrint help information
--parser-threads or --parallel-countmax(2,CPUs/2)Number of parallel read pipelines; --parallel-count is deprecated
--start-file0Start file index for partial loading
--end-file-1End file index for partial loading
--scatter-sourcesfalseScatter multiple sources for I/O optimization
--cdc-flush-interval30000The flush interval for Flink CDC
--cdc-sink-parallelism1The sink parallelism for Flink CDC
--max-read-errors1The maximum number of read error lines before exiting
--max-read-lines-1LThe maximum number of read lines, task stops when reached
--test-modefalseWhether the loader works in test mode
--use-prefilterfalseWhether to filter vertex in advance
--short-idMap a customized vertex ID to a shorter generated ID, written as label:field:type, where type is one of boolean, byte, int, long, float, double, text, blob, date and uuid; repeat the option to cover several labels
--vertex-edge-limit-1LThe maximum number of vertex’s edges
--sink-typetruespark-loader only: true writes through the HugeGraph server API, false generates HFiles and bulk-loads them into HBase
--vertex-partitions64The number of partitions of the HBase vertex table, used with --sink-type false
--edge-partitions64The number of partitions of the HBase edge table, used with --sink-type false
--vertex-table-nameHBase vertex table name, used with --sink-type false
--edge-table-nameHBase edge table name, used with --sink-type false
--hbase-zk-quorumHBase ZooKeeper quorum, used with --sink-type false
--hbase-zk-portHBase ZooKeeper port, used with --sink-type false
--hbase-zk-parentHBase ZooKeeper parent, used with --sink-type false
--restorefalseSet graph mode to RESTORING
--backendhstoreThe backend store type when creating graph if not exists
--serializerbinaryThe serializer type when creating graph if not exists
--scheduler-typedistributedThe task scheduler type when creating graph if not exists
--batch-failure-fallbacktrueWhether to fallback to single insert when batch insert fails

The loader prints its usage and exits when it is given fewer than three arguments, so -f struct.json on its own is not enough.

3.4.2 Breakpoint Continuation Mode

Usually, the Loader task takes a long time to execute. If the import interrupt process exits for some reason, and next time you want to continue the import from the interrupted point, this is the scenario of using breakpoint continuation.

The user sets the command line parameter –incremental-mode to true to open the breakpoint resume mode. The key to breakpoint continuation lies in the progress file. When the import process exits, the import progress at the time of exit will be recorded. Recorded in the progress file, the progress file is located in the ${struct} directory, the file name is like load-progress_${timestamp}, ${struct} is the prefix of the mapping file, and ${timestamp} is the start of the import moment, formatted as yyyyMMdd-HHmmss. For example, for an import task started at 2019-10-10 12:30:30, the mapping file used is struct-example.json, then the path of the progress file is the same as struct-example.json Sibling struct-example/load-progress_20191010-123030. When the directory holds several progress files, the resumed import reads the last one in name order, which is the most recent one.

Note: The generation of progress files is independent of whether –incremental-mode is turned on or not, and a progress file is generated at the end of each import.

If the data file formats are all legal and the import task is stopped by the user (CTRL + C or kill, kill -9 is not supported), that is to say, if there is no error record, the next import only needs to be set to Continue for the breakpoint.

But if the limit of –max-read-errors, –max-parse-errors or –max-insert-errors is reached because too much data is invalid or network abnormality is reached, Loader will record these original rows that failed into the failure file, after the user modifies the data lines in the failure file, set –failure-mode to true to import these “failure files” as input sources (does not affect the normal file import), Of course, if there is still a problem with the modified data line, it will be logged again to the failure file (don’t worry about duplicate lines, they are dropped when the file is closed). Failure mode lifts the three error limits above, so the whole failure file is scanned.

Each input source, that is each item of structs in the mapping file, gets its own failure file. The file is named after the id of that input source with the suffix .error and is stored in the ${struct}/failure-data directory. Every failed line is written as a pair of lines: a tip line starting with #### READ ERROR:, #### PARSE ERROR: or #### INSERT ERROR:, followed by the original data line. When the input source has a header, that header is written as JSON to a sibling ${id}.header file, so the failure file can be read back with the right columns. For example, if the mapping file has an input source with id 1 holding a vertex mapping person and an input source with id 3 holding an edge mapping knows, each of which has some error lines, you will see the following files in the ${struct}/failure-data directory when the Loader exits:

  • 1.error: the failed lines of input source 1, each preceded by its tip line
  • 1.header: the header of input source 1, written only when that input source has a header
  • 3.error: the failed lines of input source 3
  • 3.header: the header of input source 3

A .error file that turns out to be empty is deleted when the Loader exits, so only the input sources that really had failed lines leave a file behind. In incremental mode new failures are appended to the existing file, otherwise the file is rewritten from scratch.

3.4.3 logs directory file description

The log and error data during program execution will be written into the hugegraph-loader.log file.

3.4.4 Execute command

Run bin/hugegraph-loader.sh and pass in parameters

bin/hugegraph-loader.sh -g {GRAPH_NAME} -f ${INPUT_DESC_FILE} -s ${SCHEMA_FILE} -h {HOST} -p {PORT}

The script runs the JVM under JAVA_HOME when that variable is set, and java from the PATH otherwise. It passes the contents of the JVM_OPTS environment variable, then -Xmx10g and the class path built from lib/, to that JVM, so JVM_OPTS is the place to add JVM flags. Logging is configured by conf/log4j2.xml.

4 Complete example

Given below is an example in the example directory of the hugegraph-loader package. (GitHub address)

4.1 Prepare data

Vertex file: example/file/vertex_person.csv

marko,29,Beijing
vadas,27,Hongkong
josh,32,Beijing
peter,35,Shanghai
"li,nary",26,"Wu,han"
tom,null,NULL

Vertex file: example/file/vertex_software.txt

id|name|lang|price|ISBN
1|lop|java|328|ISBN978-7-107-18618-5
2|ripple|java|199|ISBN978-7-100-13678-5

Edge file: example/file/edge_knows.json

{"source_name": "marko", "target_name": "vadas", "date": "20160110", "weight": 0.5}
{"source_name": "marko", "target_name": "josh", "date": "20130220", "weight": 1.0}

Edge file: example/file/edge_created.json

{"aname": "marko", "bname": "lop", "date": "20171210", "weight": 0.4}
{"aname": "josh", "bname": "lop", "date": "20091111", "weight": 0.4}
{"aname": "josh", "bname": "ripple", "date": "20171210", "weight": 1.0}
{"aname": "peter", "bname": "lop", "date": "20170324", "weight": 0.2}

4.2 Write schema

Click to expand/collapse the schema file: example/file/schema.groovy
schema.propertyKey("name").asText().ifNotExist().create();
schema.propertyKey("age").asInt().ifNotExist().create();
schema.propertyKey("city").asText().ifNotExist().create();
schema.propertyKey("weight").asDouble().ifNotExist().create();
schema.propertyKey("lang").asText().ifNotExist().create();
schema.propertyKey("date").asText().ifNotExist().create();
schema.propertyKey("price").asDouble().ifNotExist().create();

schema.vertexLabel("person").properties("name", "age", "city").primaryKeys("name").ifNotExist().create();
schema.vertexLabel("software").properties("name", "lang", "price").primaryKeys("name").ifNotExist().create();

schema.indexLabel("personByAge").onV("person").by("age").range().ifNotExist().create();
schema.indexLabel("personByCity").onV("person").by("city").secondary().ifNotExist().create();
schema.indexLabel("personByAgeAndCity").onV("person").by("age", "city").secondary().ifNotExist().create();
schema.indexLabel("softwareByPrice").onV("software").by("price").range().ifNotExist().create();

schema.edgeLabel("knows").sourceLabel("person").targetLabel("person").properties("date", "weight").ifNotExist().create();
schema.edgeLabel("created").sourceLabel("person").targetLabel("software").properties("date", "weight").ifNotExist().create();

schema.indexLabel("createdByDate").onE("created").by("date").secondary().ifNotExist().create();
schema.indexLabel("createdByWeight").onE("created").by("weight").range().ifNotExist().create();
schema.indexLabel("knowsByWeight").onE("knows").by("weight").range().ifNotExist().create();

4.3 Write the input source mapping file example/file/struct.json

Click to expand/collapse the input source mapping file example/file/struct.json
{
  "vertices": [
    {
      "label": "person",
      "input": {
        "type": "file",
        "path": "example/file/vertex_person.csv",
        "format": "CSV",
        "header": ["name", "age", "city"],
        "charset": "UTF-8",
        "skipped_line": {
          "regex": "(^#|^//).*"
        }
      },
      "null_values": ["NULL", "null", ""]
    },
    {
      "label": "software",
      "input": {
        "type": "file",
        "path": "example/file/vertex_software.txt",
        "format": "TEXT",
        "delimiter": "|",
        "charset": "GBK"
      },
      "id": "id",
      "ignored": ["ISBN"]
    }
  ],
  "edges": [
    {
      "label": "knows",
      "source": ["source_name"],
      "target": ["target_name"],
      "input": {
        "type": "file",
        "path": "example/file/edge_knows.json",
        "format": "JSON",
        "date_format": "yyyyMMdd"
      },
      "field_mapping": {
        "source_name": "name",
        "target_name": "name"
      }
    },
    {
      "label": "created",
      "source": ["source_name"],
      "target": ["target_id"],
      "input": {
        "type": "file",
        "path": "example/file/edge_created.json",
        "format": "JSON",
        "date_format": "yyyy-MM-dd"
      },
      "field_mapping": {
        "source_name": "name"
      }
    }
  ]
}

4.4 Command to import

sh bin/hugegraph-loader.sh -g hugegraph -f example/file/struct.json -s example/file/schema.groovy

After the import is complete, statistics similar to the following will appear:

vertices/edges has been loaded this time : 8/6
--------------------------------------------------
count metrics
     input read success            : 14
     input read failure            : 0
     vertex parse success          : 8
     vertex parse failure          : 0
     vertex insert success         : 8
     vertex insert failure         : 0
     edge parse success            : 6
     edge parse failure            : 0
     edge insert success           : 6
     edge insert failure           : 0

4.5 Use Docker to load data

4.5.1 Use docker exec to load data directly
4.5.1.1 Prepare data

If you just want to try out the loader, you can import the built-in example dataset without needing to prepare additional data yourself.

If using custom data, before importing data with the loader, we need to copy the data into the container.

First, following the steps in 4.1–4.3, we can prepare the data and then use docker cp to copy the prepared data into the loader container.

Suppose we’ve prepared the corresponding dataset following the above steps, stored in the hugegraph-dataset folder with the following file structure:

tree -f hugegraph-dataset/

hugegraph-dataset
├── hugegraph-dataset/edge_created.json
├── hugegraph-dataset/edge_knows.json
├── hugegraph-dataset/schema.groovy
├── hugegraph-dataset/struct.json
├── hugegraph-dataset/vertex_person.csv
└── hugegraph-dataset/vertex_software.txt

Copy the files into the container.

docker cp hugegraph-dataset loader:/loader/dataset
docker exec -it loader ls /loader/dataset

edge_created.json  edge_knows.json  schema.groovy  struct.json  vertex_person.csv  vertex_software.txt
4.5.1.2 Data loading

Taking the built-in example dataset as an example, we can use the following command to load the data.

If you need to import your custom dataset, you need to modify the paths for -f (data script) and -s (schema) configurations.

You can refer to 3.4.1-Parameter description for the rest of the parameters.

docker exec -it loader bin/hugegraph-loader.sh -g hugegraph -f example/file/struct.json -s example/file/schema.groovy -h server -p 8080

If loading a custom dataset, following the previous example, you would use:

docker exec -it loader bin/hugegraph-loader.sh -g hugegraph -f /loader/dataset/struct.json -s /loader/dataset/schema.groovy -h server -p 8080

If loader and server are in the same Docker network, you can specify -h {server_container_name}; otherwise, you need to specify the IP of the server host (in our example, server_container_name is server).

Then we can see the result:

HugeGraphLoader worked in NORMAL MODE
vertices/edges loaded this time : 8/6
--------------------------------------------------
count metrics
    input read success            : 14                  
    input read failure            : 0                   
    vertex parse success          : 8                   
    vertex parse failure          : 0                   
    vertex insert success         : 8                   
    vertex insert failure         : 0                   
    edge parse success            : 6                   
    edge parse failure            : 0                   
    edge insert success           : 6                   
    edge insert failure           : 0                   
--------------------------------------------------
meter metrics
    total time                    : 0.199s              
    read time                     : 0.046s              
    load time                     : 0.153s              
    vertex load time              : 0.077s              
    vertex load rate(vertices/s)  : 103                 
    edge load time                : 0.112s              
    edge load rate(edges/s)       : 53   

You can also use curl or hubble to observe the import result. Here’s an example using curl:

> curl "http://localhost:8080/graphs/hugegraph/graph/vertices" | gunzip
{"vertices":[{"id":1,"label":"software","type":"vertex","properties":{"name":"lop","lang":"java","price":328.0}},{"id":2,"label":"software","type":"vertex","properties":{"name":"ripple","lang":"java","price":199.0}},{"id":"1:tom","label":"person","type":"vertex","properties":{"name":"tom"}},{"id":"1:josh","label":"person","type":"vertex","properties":{"name":"josh","age":32,"city":"Beijing"}},{"id":"1:marko","label":"person","type":"vertex","properties":{"name":"marko","age":29,"city":"Beijing"}},{"id":"1:peter","label":"person","type":"vertex","properties":{"name":"peter","age":35,"city":"Shanghai"}},{"id":"1:vadas","label":"person","type":"vertex","properties":{"name":"vadas","age":27,"city":"Hongkong"}},{"id":"1:li,nary","label":"person","type":"vertex","properties":{"name":"li,nary","age":26,"city":"Wu,han"}}]}

If you want to check the import result of edges, you can use curl "http://localhost:8080/graphs/hugegraph/graph/edges" | gunzip.

4.5.2 Enter the docker container to load data

Besides using docker exec directly for data import, we can also enter the container for data loading. The basic process is similar to 4.5.1.

Enter the container by docker exec -it loader bash and execute the command:

sh bin/hugegraph-loader.sh -g hugegraph -f example/file/struct.json -s example/file/schema.groovy -h server -p 8080

The results of the execution will be similar to those shown in 4.5.1.

4.6 Import data by spark-loader

The current source uses Spark 3.2.2 and Scala 2.12. Other combinations need independent verification.

The parameters of spark-loader are divided into two parts. Note: Because the abbreviations of these two-parameter names have overlapping parts, please use the full name of the parameter. And there is no need to guarantee the order between the two parameters.

Example:

sh bin/hugegraph-spark-loader.sh --master yarn \
--deploy-mode cluster --name spark-hugegraph-loader --file ./hugegraph.json \
--username admin --token admin --host xx.xx.xx.xx --port 8093 \
--graph graph-test --num-executors 6 --executor-cores 16 --executor-memory 15g

bin/hugegraph-spark-loader.sh submits org.apache.hugegraph.loader.spark.HugeGraphSparkLoader through ${SPARK_HOME}/bin/spark-submit, so SPARK_HOME has to point at a Spark installation. Every jar under lib/ is put on the class path. The Spark application name defaults to hugegraph-spark-loader and can be changed through the APP_NAME environment variable.

bin/get-params.sh splits the command line: only the options below are handed to the loader, every other argument is passed to spark-submit unchanged. The splitter matches long option names only, so short forms such as -f and -g are not recognised.

--graph --schema --host --port --username --token --protocol
--trust-store-file --trust-store-password --clear-all-data --clear-timeout
--incremental-mode --failure-mode --batch-insert-threads --single-insert-threads
--max-conn --max-conn-per-route --batch-size --max-parse-errors --max-insert-errors
--timeout --shutdown-timeout --retry-times --retry-interval --check-vertex
--print-progress --dry-run --sink-type --vertex-partitions --edge-partitions --help

--file is treated separately: with --deploy-mode cluster the mapping file is shipped to the executors through --files and the loader receives only its base name, otherwise the path is passed through as written.

In this mode the loader reads FILE, HDFS and JDBC input sources; a KAFKA or GRAPH input source is rejected.

By default (--sink-type true) each Spark partition opens a HugeClient and writes vertices and edges through the HugeGraph server API. With --sink-type false the loader generates HFiles and bulk-loads them into HBase instead, taking the table names and ZooKeeper settings from --vertex-table-name, --edge-table-name, --hbase-zk-quorum, --hbase-zk-port, --hbase-zk-parent, --vertex-partitions and --edge-partitions.

The current source uses Flink 1.13.5 with flink-connector-mysql-cdc 2.2.1 and Scala 2.12. Other combinations need independent verification.

bin/hugegraph-flinkcdc-loader.sh submits org.apache.hugegraph.loader.flink.HugeGraphFlinkCDCLoader through ${FLINK_HOME}/bin/flink run, so FLINK_HOME has to be set. The job captures MySQL change events with Flink CDC and applies them to the graph, which keeps the graph in step with the source tables.

The mapping file uses the same format as for the command-line loader, but every input source has to be a JDBC input source over MySQL: the loader takes url, database, table, username and password from it and parses the host and port out of url. Vertex and edge mappings work as usual. --cdc-flush-interval and --cdc-sink-parallelism in 3.4.1 apply to this mode only.

The command line is split by bin/get-params.sh in the same way as for spark-loader, with the arguments that are not loader options going to flink run.

Example:

sh bin/hugegraph-flinkcdc-loader.sh --file ./mysql-cdc.json \
--host xx.xx.xx.xx --port 8080 --graph hugegraph --username admin --token admin

2.5 - Graph export and migration

Choose an export or migration tool when you need to back up, export, or move data between graphs. Tools is suited to standalone operations and backups; SeaTunnel Source connects graph reads to an expandable data pipeline.

2.5.1 - Export and Migrate Graph Data with SeaTunnel Source

If you need to copy data from one HugeGraph graph to another, use graph2graph: HugeGraph Source reads vertices and edges from the source graph (graph A), and HugeGraph Sink writes them to the target graph (graph B), with an optional Transform in between. The data path is graph A → HugeGraph Source → (optional Transform) → HugeGraph Sink → graph B. If you need to export graph data to a file, JDBC, Kafka, or another system, use graph2any, where a downstream Sink receives the records read by HugeGraph Source. This page covers both job types.

Version requirement: This guide targets SeaTunnel 3.0+

Before starting, complete the shared environment and configuration steps on the import page. They cover JDK, HOCON, plugin installation, and the sample graph model.

1 Migrate a HugeGraph graph (graph2graph)

The following example migrates person vertices and knows edges from a source graph. Use a separate target graph. This section uses CUSTOMIZE_STRING to preserve vertex IDs. Do not reuse the person label created earlier with PRIMARY_KEY.

These two jobs migrate only the selected labels and properties. They do not copy every source schema setting, such as indexes and TTLs. Pause writes to the source graph during the migration so both jobs read a consistent point in time. Afterward, compare vertex and edge counts and sample properties.

Regenerating a primary key can change 1:marko to 2:marko; CUSTOMIZE_STRING preserves the original ID so edge endpoints still resolve

1.1 Migrate vertices first

Source adds a ~id column for the original ID, and Sink stores it as a string. Do not declare ~id in schema.fields; manually declaring this reserved column is rejected.

Expand the configuration and save it as config/graph2graph-person.conf
env {
  job.mode = "BATCH"
}

source {
  HugeGraph {
    host = "source-hugegraph"
    port = 8080
    graph_name = "hugegraph"
    graph_space = "DEFAULT"
    label = "person"
    label_type = "VERTEX"
    schema = {
      fields = {
        name = "string"
        age = "int"
      }
    }
  }
}

sink {
  HugeGraph {
    host = "target-hugegraph"
    port = 8080
    graph_name = "hugegraph"
    graph_space = "DEFAULT"
    batch_failure_fallback = false
    mappings = [
      {
        type = "VERTEX"
        label = "person"
        idStrategy = "CUSTOMIZE_STRING"
        idFields = ["~id"]
        properties = ["name", "age"]
      }
    ]
  }
}
./bin/seatunnel.sh --config ./config/graph2graph-person.conf -m local

1.2 Migrate edges second

After the vertex job succeeds, use the ~source_id and ~target_id columns added by Source to locate endpoints. Because the previous job preserved the original IDs, these columns can refer directly to vertices in the target graph.

Expand the configuration and save it as config/graph2graph-knows.conf
env {
  job.mode = "BATCH"
}

source {
  HugeGraph {
    host = "source-hugegraph"
    port = 8080
    graph_name = "hugegraph"
    graph_space = "DEFAULT"
    label = "knows"
    label_type = "EDGE"
    schema = {
      fields = {
        since = "int"
      }
    }
  }
}

sink {
  HugeGraph {
    host = "target-hugegraph"
    port = 8080
    graph_name = "hugegraph"
    graph_space = "DEFAULT"
    check_vertex = true
    batch_failure_fallback = false
    mappings = [
      {
        type = "EDGE"
        label = "knows"
        sourceConfig = {
          label = "person"
          idFields = ["~source_id"]
        }
        targetConfig = {
          label = "person"
          idFields = ["~target_id"]
        }
        properties = ["since"]
      }
    ]
  }
}
./bin/seatunnel.sh --config ./config/graph2graph-knows.conf -m local

This example checks endpoints and makes write errors fail the job. The default check_vertex = false does not guarantee a consistent result: a missing endpoint can create a dangling edge, so a successful job is not a substitute for checking the migrated graph.

Why preserve IDs? A HugeGraph PRIMARY_KEY ID contains the internal ID of the vertex label, and that internal ID can differ between graphs. For example, a source vertex can be 1:marko, while regenerating the primary key in the target graph can produce 2:marko. Reusing the source edge endpoints after regenerating vertex IDs can connect edges to the wrong vertices. This example stores the original ID as a string, which changes the target graph’s ID strategy

When Source reads every label, omit label to read all labels of label_type (default VERTEX). It produces one output table per label. Bind each Sink mapping to its table with sourceTable, for example sourceTable = "default.person"; use the full table name shown in the Writer log for the exact value. Do not reuse the single-label configuration from this section. See the HugeGraph Source documentation for other limitations.

2 Export to another system (graph2any)

graph2any uses HugeGraph Source[1] to read vertices or edges and sends them to a downstream Sink. The example below exports person vertices to local JSON files; to export to JDBC, Kafka, or another system, replace LocalFile[2] and its options.

env {
  job.mode = "BATCH"
}

source {
  HugeGraph {
    host = "hugegraph"
    port = 8080
    graph_name = "hugegraph"
    graph_space = "DEFAULT"
    label = "person"
    label_type = "VERTEX"
    schema = {
      fields = {
        name = "string"
        age = "int"
      }
    }
  }
}

sink {
  LocalFile {
    path = "/tmp/hugegraph-export/${table_name}"
    file_format_type = "json"
  }
}

Save this as config/graph2file-person.conf and run it from the SeaTunnel installation directory:

./bin/seatunnel.sh --config ./config/graph2file-person.conf -m local

To export edges, change the Source label to an edge label, set label_type = "EDGE", and declare the edge properties in schema.fields. Source also outputs the reserved columns ~source_id, ~source_label, ~target_id, and ~target_label; write them to the file or pass them to downstream transforms as needed.

This page covers row reads and writes. It does not copy source indexes, TTLs, or other schema settings. For the complete Source options and shared environment guidance, return to the SeaTunnel graph import guide[3].

3 References

Connectors

[1] HugeGraph Source
[2] LocalFile Sink

Related guide

[3] SeaTunnel graph import guide

2.6 - Tools Quick Start

1 HugeGraph-Tools Overview

HugeGraph-Tools is an automated deployment, management and backup/restore component of HugeGraph.

Testing Guide: For running HugeGraph-Tools tests locally, please refer to HugeGraph Toolchain Local Testing Guide

2 Get HugeGraph-Tools

HugeGraph-Tools is included in the Toolchain distribution. You can download the distribution or build it from source.

  • Download the compiled tarball
  • Clone source code then compile and install

2.1 Download the compiled archive

Download the latest version of the HugeGraph-Toolchain package:

export VERSION=1.7.0
export ARCHIVE="apache-hugegraph-toolchain-incubating-${VERSION}"
wget "https://downloads.apache.org/hugegraph/${VERSION}/${ARCHIVE}.tar.gz"
tar zxf "${ARCHIVE}.tar.gz"
# hugegraph-tools ships inside the toolchain package, in a directory
# whose version suffix is the same as the archive's
cd "${ARCHIVE}/apache-hugegraph-tools-incubating-${VERSION}"

2.2 Clone source code to compile and install

Please ensure that the wget command is installed before compiling the source code

Download the latest version of the HugeGraph-Tools source package:

# 1. get from github
git clone https://github.com/apache/hugegraph-toolchain.git

# 2. Download a released source package
export VERSION=1.7.0
export ARCHIVE="apache-hugegraph-toolchain-incubating-${VERSION}"
wget "https://downloads.apache.org/hugegraph/${VERSION}/${ARCHIVE}-src.tar.gz"

Compile and generate tar package:

cd hugegraph-toolchain
mvn package -pl hugegraph-tools -am -DskipTests -ntp

The package is generated as hugegraph-tools/target/apache-hugegraph-tools-${version}.tar.gz, and the unpacked directory hugegraph-tools/apache-hugegraph-tools-${version} (containing bin/ and lib/) is created next to it.

3 How to use

3.1 Function overview

After decompression, enter the apache-hugegraph-tools-${version} directory, you can use bin/hugegraph or bin/hugegraph help to view the usage information, and bin/hugegraph help <sub-command> to view the usage of a single sub-command. mainly divided:

  • Graph management type, graph-mode-set, graph-mode-get, graph-list, graph-get, graph-clear, graph-create, graph-clone and graph-drop
  • Asynchronous task management type, task-list, task-get, task-delete, task-cancel and task-clear
  • Gremlin type, gremlin-execute and gremlin-schedule
  • Backup/Restore type, backup, restore, migrate, schedule-backup and dump
  • Authentication data backup/restore type, auth-backup and auth-restore
  • Install deployment type, deploy, clear, start-all and stop-all
Usage: hugegraph [options] [command] [command options]
3.2 [options]-Global Variable

options is a global variable of HugeGraph-Tools, which can be configured in hugegraph-tools/bin/hugegraph, including:

  • –graph,HugeGraph-Tools The name of the graph to operate on, the default value is hugegraph
  • –url,The service address of HugeGraph-Server, the default is http://127.0.0.1:8080
  • –user,When HugeGraph-Server opens authentication, pass username
  • –password,When HugeGraph-Server opens authentication, pass the user’s password
  • –timeout,Timeout when connecting to HugeGraph-Server, the default is 30s
  • –trust-store-file,The path of the certificate file, when –url uses https, the truststore file used by HugeGraph-Client, the default is empty, which means using the built-in truststore file conf/hugegraph.truststore of hugegraph-tools
  • –trust-store-password,The password of the certificate file, when –url uses https, the password of the truststore used by HugeGraph-Client, the default is empty, representing the password of the built-in truststore file of hugegraph-tools
  • –throw-mode, whether HugeGraph-Tools throws the exception instead of printing the error message and exiting, the default is false (mainly used by tests)

The protocol is taken from the scheme of –url: use https://... to connect over https. –trust-store-file and –trust-store-password can only be set when –url uses https, and both –user and –password must be given together or omitted together.

The above global variables can also be set through environment variables. One way is to use export on the command line to set temporary environment variables, which are valid until the command line is closed

Global VariableEnvironment VariableExample
–urlHUGEGRAPH_URLexport HUGEGRAPH_URL=http://127.0.0.1:8080
–graphHUGEGRAPH_GRAPHexport HUGEGRAPH_GRAPH=hugegraph
–userHUGEGRAPH_USERNAMEexport HUGEGRAPH_USERNAME=admin
–passwordHUGEGRAPH_PASSWORDexport HUGEGRAPH_PASSWORD=test
–timeoutHUGEGRAPH_TIMEOUTexport HUGEGRAPH_TIMEOUT=30
–trust-store-fileHUGEGRAPH_TRUST_STORE_FILEexport HUGEGRAPH_TRUST_STORE_FILE=/tmp/trust-store
–trust-store-passwordHUGEGRAPH_TRUST_STORE_PASSWORDexport HUGEGRAPH_TRUST_STORE_PASSWORD=xxxx

Another way is to set the environment variable in the bin/hugegraph script:

#!/bin/bash

# Set environment here if needed
#export HUGEGRAPH_URL=
#export HUGEGRAPH_GRAPH=
#export HUGEGRAPH_USERNAME=
#export HUGEGRAPH_PASSWORD=
#export HUGEGRAPH_TIMEOUT=
#export HUGEGRAPH_TRUST_STORE_FILE=
#export HUGEGRAPH_TRUST_STORE_PASSWORD=

bin/hugegraph also reads JAVA_HOME (a warning is printed when it is not set, and it is needed for https) and JAVA_OPTIONS (JVM options; when it is empty the script uses -Xms512m plus an -Xmx computed from the free memory of the machine).

3.3 Graph Management Type, graph-mode-set, graph-mode-get, graph-list, graph-get, graph-clear, graph-create, graph-clone and graph-drop
  • graph-mode-set, set graph restore mode
    • –graph-mode or -m, required, specifies the mode to be set, legal values include [NONE, RESTORING, MERGING, LOADING]
  • graph-mode-get, get graph restore mode
  • graph-list, list all graphs in a HugeGraph-Server
  • graph-get, get a graph and its storage backend type
  • graph-clear, clear all schema and data of a graph
    • –confirm-message or -c, required, delete confirmation information, manual input is required, double confirmation to prevent accidental deletion, “I’m sure to delete all data”, including double quotes
  • graph-create, create a new graph with configuration file
    • –name or -n, optional, the name of the new graph, default is g
    • –file or -f, the path to the graph configuration file, the content of the file is sent to HugeGraph-Server as the config of the new graph
  • graph-clone, clone an existing graph
    • –name or -n, optional, the name of the cloned graph, default is g
    • –clone-graph-name, optional, the name of the source graph to clone from, default is hugegraph
  • graph-drop, drop a graph (different from graph-clear, this completely removes the graph)
    • –confirm-message or -c, required, confirmation message “I’m sure to drop the graph”, including double quotes

graph-create, graph-clone, graph-clear and graph-drop raise –timeout to at least 300 seconds.

When you need to restore the backup graph to a new graph, you need to set the graph mode to RESTORING mode; when you need to merge the backup graph into an existing graph, you need to first set the graph mode to MERGING model.

3.4 Asynchronous task management Type,task-list、task-get、task-delete、task-cancel and task-clear
  • task-list,List the asynchronous tasks in a graph, which can be filtered according to the status of the tasks
    • –status,Optional, specify the status of the task to view, i.e. filter tasks by status, legal values include [UNKNOWN, NEW, QUEUED, RESTORING, RUNNING, SUCCESS, CANCELLED, FAILED] (case insensitive)
    • –limit,Optional, specify the number of tasks to be obtained, the default is -1, which means to obtain all eligible tasks, a value passed explicitly must be positive
  • task-get,Get detailed information about an asynchronous task
    • –task-id,Required, specifies the ID of the asynchronous task
  • task-delete,Delete information about an asynchronous task
    • –task-id,Required, specifies the ID of the asynchronous task
  • task-cancel,Cancel the execution of an asynchronous task
    • –task-id,Required, the ID of the asynchronous task to cancel
  • task-clear,Clean up completed asynchronous tasks
    • –force,Optional. When set, it means to clean up all asynchronous tasks. Unfinished ones are canceled first, and then all asynchronous tasks are cleared. By default, only completed asynchronous tasks are cleaned up
3.5 Gremlin Type,gremlin-execute and gremlin-schedule

⚠️ SEC Reminder: The execution of Gremlin depends on the actual logic of the statements, which may involve scenarios such as large-scale data modification and high-risk system calls with potential implicit hazards. Please use this tool only in secure and trusted network environments. It is imperative to configure and secure HugeGraph-Server with the Authentication System (Auth) and an IP Whitelist to restrict execution requests on the server side. Never hand over the tool or expose the execution entry to unauthorized personnel.

  • gremlin-execute, send Gremlin statements to HugeGraph-Server to execute query or modification operations, execute synchronously, and return results after completion
    • –file or -f, specify the script file to execute, UTF-8 encoding, mutually exclusive with –script
    • –script or -s, specifies the script string to execute, mutually exclusive with –file
    • –aliases or -a, Gremlin alias settings, the format is: key1=value1,key2=value2,…
    • –bindings or -b, Gremlin binding settings, the format is: key1=value1,key2=value2,…
    • –language or -l, the language of the Gremlin script, the default is gremlin-groovy

    –file and –script are mutually exclusive, one of them must be set

  • gremlin-schedule, send Gremlin statements to HugeGraph-Server to perform query or modification operations, asynchronous execution, and return the asynchronous task id immediately after the task is submitted
    • –file or -f, specify the script file to execute, UTF-8 encoding, mutually exclusive with –script
    • –script or -s, specifies the script string to execute, mutually exclusive with –file
    • –bindings or -b, Gremlin binding settings, the format is: key1=value1,key2=value2,…
    • –language or -l, the language of the Gremlin script, the default is gremlin-groovy

    –file and –script are mutually exclusive, one of them must be set

3.6 Backup/Restore Type
  • backup, back up the schema or data in a certain graph out of the HugeGraph system, and store it on the local disk or HDFS in the form of JSON
    • –format, the backup format, optional values include [json, text], the default is json
    • –all-properties, whether to back up all properties of vertices/edges, only valid when –format is text, default false
    • –label, the vertex label or edge label to be backed up, only applied when –format is text; when it is set, –huge-types must name exactly one type and that type must be vertex or edge, otherwise the command fails
    • –properties, properties of vertices/edges to be backed up, separated by commas, only valid when –format is text, valid only when backing up vertices or edges
    • –compress, whether to compress data during backup, the default is true
    • –directory or -d, the directory to store schema or data, the default is ‘./{graphName}’ for local directory, and ‘{fs.default.name}/{graphName}’ for HDFS
    • –huge-types or -t, the data types to be backed up, separated by commas, the optional value is ‘all’ or a combination of one or more [vertex, edge, vertex_label, edge_label, property_key, index_label], ‘all’ Represents all 6 types, namely vertices, edges and all schemas, ‘schema’ represents the 4 schema types [vertex_label, edge_label, property_key, index_label]
    • –log or -l, specify the log directory, the default is ./logs
    • –retry, specify the number of failed retries, the default is 3
    • –thread-num or -T, the number of threads to use, default is Math.min(10, Math.max(4, CPUs / 2))
    • –split-size or -s, specifies the size of splitting vertices or edges when backing up, the default is 1048576, and it must be at least 1048576 (1M)
    • -D, use the mode of -Dkey=value to specify dynamic parameters, and specify HDFS configuration items when backing up data to HDFS, for example: -Dfs.default.name=hdfs://localhost:9000

    If –timeout is less than 120 seconds, backup (and the backup step of migrate) uses 120 seconds

  • restore, restore schema or data stored in JSON format to a new graph (RESTORING mode) or merge into an existing graph (MERGING mode)
    • –directory or -d, the directory to store schema or data, the default is ‘./{graphName}’ for local directory, and ‘{fs.default.name}/{graphName}’ for HDFS
    • –clean, whether to delete the directory specified by –directory after the recovery map is completed, the default is false
    • –huge-types or -t, data types to restore, separated by commas, optional value is ‘all’ or a combination of one or more [vertex, edge, vertex_label, edge_label, property_key, index_label], ‘all’ Represents all 6 types, namely vertices, edges and all schemas, ‘schema’ represents the 4 schema types [vertex_label, edge_label, property_key, index_label]
    • –log or -l, specify the log directory, the default is ./logs
    • –retry, specify the number of failed retries, the default is 3
    • –thread-num or -T, the number of threads to use, default is Math.min(10, Math.max(4, CPUs / 2))
    • -D, use the mode of -Dkey=value to specify dynamic parameters, which are used to specify HDFS configuration items when restoring graphs from HDFS, for example: -Dfs.default.name=hdfs://localhost:9000

    restore command can be used only if –format is executed as backup for json restore requires the graph to be in RESTORING or MERGING mode (set it with graph-mode-set first), otherwise the command fails

  • migrate, migrate the currently connected graph to another HugeGraphServer
    • –target-graph, the name of the target graph, the default is hugegraph
    • –target-url, the HugeGraphServer where the target graph is located, the default is http://127.0.0.1:8081
    • –target-user, the username used to access the target graph
    • –target-password, the password to access the target map
    • –target-timeout, the timeout for accessing the target map
    • –target-trust-store-file, access the truststore file used by the target graph
    • –target-trust-store-password, the password to access the truststore used by the target map
    • –directory or -d, during the migration process, the directory where the schema or data of the source graph is stored. For a local directory, the default is ‘./{graphName}’; for HDFS, the default is ‘{fs.default.name}/ {graphName}’
    • –huge-types or -t, the data types to be migrated, separated by commas, the optional value is ‘all’ or a combination of one or more [vertex, edge, vertex_label, edge_label, property_key, index_label], ‘all’ Represents all 6 types, namely vertices, edges and all schemas, ‘schema’ represents the 4 schema types [vertex_label, edge_label, property_key, index_label]
    • –log or -l, specify the log directory, the default is ./logs
    • –retry, specify the number of failed retries, the default is 3
    • –thread-num or -T, the number of threads to use, default is Math.min(10, Math.max(4, CPUs / 2))
    • –split-size or -s, specify the size of the vertex or edge block when backing up the source graph during the migration process, the default is 1048576, and it must be at least 1048576 (1M)
    • -D, use the mode of -Dkey=value to specify dynamic parameters, which are used to specify HDFS configuration items when the data needs to be backed up to HDFS during the migration process, for example: -Dfs.default.name=hdfs://localhost: 9000
    • –graph-mode or -m, the mode to set the target graph when restoring the source graph to the target graph, legal values include [RESTORING, MERGING], the default is RESTORING. The target graph is switched to this mode during the migration and switched back to its original mode afterwards
    • –keep-local-data, whether to keep the backup of the source map generated in the process of migrating the map, the default is false, that is, the backup of the source map is not kept after the default migration map ends
  • schedule-backup, periodically back up the graph and keep a certain number of the latest backups (currently only supports local file systems)
    • –directory or -d, required, specifies the directory of the backup data
    • –backup-num, optional, specifies the number of latest backups to save, defaults to 3
    • –interval, an optional item, specifies the backup cycle, the format is the same as the Linux crontab format, the default is “0 0 * * *” (every day at 00:00)

    schedule-backup adds a crontab entry that runs backup -t all into {directory}/{graph}/hugegraph-backup-{yyMMddHHmm}/ and keeps only the latest –backup-num backups. A relative –directory is resolved against the hugegraph-tools home directory, and {directory}/{graph} must not exist yet

  • dump, export all vertices and edges in the graph, using the vertex vertex-edge1 vertex-edge2... JSON format by default. To customize the format, implement a Formatter subclass such as CustomFormatter under hugegraph-tools/src/main/java/org/apache/hugegraph/formatter, then select it when running the command: bin/hugegraph dump -f CustomFormatter
    • –formatter or -f, specify the formatter to use, the default is JsonFormatter
    • –directory or -d, the directory where schema or data is stored, the default is ‘./{graphName}’ for local directory, and ‘{fs.default.name}/{graphName}’ for HDFS
    • –log or -l, specify the log directory, the default is ./logs
    • –retry, specify the number of failed retries, the default is 3
    • –thread-num or -T, the number of threads to use, default is Math.min(10, Math.max(4, CPUs / 2))
    • –split-size or -s, specifies the size of splitting vertices or edges when backing up, the default is 1048576, and it must be at least 1048576 (1M)
    • -D, use the mode of -Dkey=value to specify dynamic parameters, and specify HDFS configuration items when backing up data to HDFS, for example: -Dfs.default.name=hdfs://localhost:9000
3.7 Authentication data backup/restore type
  • auth-backup, backup authentication data to a specified directory
    • –types or -t, types of authentication data to back up, separated by commas, optional value is ‘all’ or a combination of one or more [user, group, target, belong, access], ‘all’ represents all 5 types; ‘belong’ requires ‘user’ and ‘group’ to be included, ‘access’ requires ‘group’ and ’target’ to be included
    • –directory, directory to store backup data, the default is ‘./auth-backup-restore’ for local directory, and ‘{fs.default.name}/auth-backup-restore’ for HDFS (this option has no -d short form)
    • –retry, specify the number of failed retries, the default is 3
    • -D, use the mode of -Dkey=value to specify dynamic parameters, and specify HDFS configuration items when backing up data to HDFS, for example: -Dfs.default.name=hdfs://localhost:9000
  • auth-restore, restore authentication data from a specified directory
    • –types or -t, types of authentication data to restore, separated by commas, optional value is ‘all’ or a combination of one or more [user, group, target, belong, access], ‘all’ represents all 5 types; ‘belong’ requires ‘user’ and ‘group’ to be included, ‘access’ requires ‘group’ and ’target’ to be included
    • –directory, directory where backup data is stored, the default is ‘./auth-backup-restore’ for local directory, and ‘{fs.default.name}/auth-backup-restore’ for HDFS (this option has no -d short form)
    • –retry, specify the number of failed retries, the default is 3
    • –strategy, conflict handling strategy, optional values are [stop, ignore], default is stop. stop means stop restoring when encountering conflicts, ignore means ignore conflicts and continue restoring
    • –init-password, initial password to set when restoring users, required when –types includes user
    • -D, use the mode of -Dkey=value to specify dynamic parameters, which are used to specify HDFS configuration items when restoring data from HDFS, for example: -Dfs.default.name=hdfs://localhost:9000
3.8 Install the deployment type
  • deploy, one-click download, install and start HugeGraph-Server and HugeGraph-Studio
    • -v, required, specifies the HugeGraph-Server and HugeGraph-Studio version to install, must be one of the versions listed in bin/version-map.yaml (0.6, 0.7, 0.8, 0.9, 0.10), which maps it to the matching server and studio release versions
    • -p, required, specifies the installed HugeGraph-Server and HugeGraph-Studio directories
    • -u, optional, specifies the link to download the HugeGraph-Server and HugeGraph-Studio compressed packages
  • clear, clean up HugeGraph-Server and HugeGraph-Studio directories and tarballs (refuses to run while a matching server or studio process is still alive, and prompts before each removal)
    • -p, required, specifies the directory of HugeGraph-Server and HugeGraph-Studio to be cleaned
  • start-all, start HugeGraph-Server and HugeGraph-Studio with one click
    • -v, required, specifies the installed HugeGraph-Server and HugeGraph-Studio version to start, same values as deploy
    • -p, required, specifies the directory where HugeGraph-Server and HugeGraph-Studio are installed
  • stop-all, close HugeGraph-Server and HugeGraph-Studio with one click

deploy, start-all, clear and stop-all are handed by bin/hugegraph straight to the shell scripts bin/deploy.sh, bin/start-all.sh, bin/clear.sh and bin/stop-all.sh, so the global options and environment variables in 3.2 do not apply to them.

There is an optional parameter -u in the deploy command. When provided, the specified download address will be used instead of the default download address to download the tar package, and the address will be written into the ~/hugegraph-download-url-prefix file; if no address is specified later When -u and ~/hugegraph-download-url-prefix are not specified, the tar package will be downloaded from the address specified by ~/hugegraph-download-url-prefix; if there is neither -u nor ~/hugegraph-download-url-prefix, it will be downloaded from the default download address https://github.com/hugegraph

3.9 Specific command parameters

The specific parameters of each subcommand are as follows:

Usage: hugegraph [options] [command] [command options]
  Options:
    --graph
      Name of graph
      Default: hugegraph
    --password
      Password of user
    --throw-mode
      Whether the hugegraph-tools work to throw an exception
      Default: false
    --timeout
      Connection timeout
      Default: 30
    --trust-store-file
      The path of client truststore file used when https protocol is enabled
    --trust-store-password
      The password of the client truststore file used when the https protocol 
      is enabled
    --url
      The URL of HugeGraph-Server
      Default: http://127.0.0.1:8080
    --user
      Name of user
  Commands:
    graph-create      Create graph with config
      Usage: graph-create [options]
        Options:
          --file, -f
            Creating graph config file
          --name, -n
            The name of new created graph, default is g
            Default: g

    graph-clone      Clone graph
      Usage: graph-clone [options]
        Options:
          --clone-graph-name
            The name of cloned graph, default is hugegraph
            Default: hugegraph
          --name, -n
            The name of new created graph, default is g
            Default: g

    graph-list      List all graphs
      Usage: graph-list

    graph-get      Get graph info
      Usage: graph-get

    graph-clear      Clear graph schema and data
      Usage: graph-clear [options]
        Options:
        * --confirm-message, -c
            Confirm message of graph clear is "I'm sure to delete all data". 
            (Note: include "")

    graph-drop      Drop graph
      Usage: graph-drop [options]
        Options:
        * --confirm-message, -c
            Confirm message of graph clear is "I'm sure to drop the graph". 
            (Note: include "")

    graph-mode-set      Set graph mode
      Usage: graph-mode-set [options]
        Options:
        * --graph-mode, -m
            Graph mode, include: [NONE, RESTORING, MERGING]
            Possible Values: [NONE, RESTORING, MERGING, LOADING]

    graph-mode-get      Get graph mode
      Usage: graph-mode-get

    task-list      List tasks
      Usage: task-list [options]
        Options:
          --limit
            Limit number, no limit if not provided
            Default: -1
          --status
            Status of task

    task-get      Get task info
      Usage: task-get [options]
        Options:
        * --task-id
            Task id
            Default: 0

    task-delete      Delete task
      Usage: task-delete [options]
        Options:
        * --task-id
            Task id
            Default: 0

    task-cancel      Cancel task
      Usage: task-cancel [options]
        Options:
        * --task-id
            Task id
            Default: 0

    task-clear      Clear completed tasks
      Usage: task-clear [options]
        Options:
          --force
            Force to clear all tasks, cancel all uncompleted tasks firstly, 
            and delete all completed tasks
            Default: false

    gremlin-execute      Execute Gremlin statements
      Usage: gremlin-execute [options]
        Options:
          --aliases, -a
            Gremlin aliases, valid format is: 'key1=value1,key2=value2...'
            Default: {}
          --bindings, -b
            Gremlin bindings, valid format is: 'key1=value1,key2=value2...'
            Default: {}
          --file, -f
            Gremlin Script file to be executed, UTF-8 encoded, exclusive to 
            --script 
          --language, -l
            Gremlin script language
            Default: gremlin-groovy
          --script, -s
            Gremlin script to be executed, exclusive to --file

    gremlin-schedule      Execute Gremlin statements as asynchronous job
      Usage: gremlin-schedule [options]
        Options:
          --bindings, -b
            Gremlin bindings, valid format is: 'key1=value1,key2=value2...'
            Default: {}
          --file, -f
            Gremlin Script file to be executed, UTF-8 encoded, exclusive to 
            --script 
          --language, -l
            Gremlin script language
            Default: gremlin-groovy
          --script, -s
            Gremlin script to be executed, exclusive to --file

    backup      Backup graph schema/data. If directory is on HDFS, use -D to 
            set HDFS params. For example: 
            -Dfs.default.name=hdfs://localhost:9000 
      Usage: backup [options]
        Options:
          --all-properties
            All properties to be backup flag
            Default: false
          --compress
            compress flag
            Default: true
          --directory, -d
            Directory of graph schema/data, default is './{graphname}' in 
            local file system or '{fs.default.name}/{graphname}' in HDFS
          --format
            File format, valid is [json, text]
            Default: json
          --huge-types, -t
            Type of schema/data. Concat with ',' if more than one. Other types 
            include 'all' and 'schema'. 'all' means all vertices, edges and 
            schema. In other words, 'all' equals with 'vertex, edge, 
            vertex_label, edge_label, property_key, index_label'. 'schema' 
            equals with 'vertex_label, edge_label, property_key, index_label'.
            Default: [PROPERTY_KEY, VERTEX_LABEL, EDGE_LABEL, INDEX_LABEL, VERTEX, EDGE]
          --label
            Vertex label or edge label, only valid when type is vertex or edge
          --log, -l
            Directory of log
            Default: ./logs
          --properties
            Vertex or edge properties to backup, only valid when type is 
            vertex or edge
            Default: []
          --retry
            Retry times, default is 3
            Default: 3
          --split-size, -s
            Split size of shard
            Default: 1048576
          --thread-num, -T
            Threads number to use, default is Math.min(10, Math.max(4, CPUs / 
            2)) 
            Default: 0
          -D
            HDFS config parameters
            Syntax: -Dkey=value
            Default: {}

    schedule-backup      Schedule backup task
      Usage: schedule-backup [options]
        Options:
          --backup-num
            The number of latest backups to keep
            Default: 3
        * --directory, -d
            The directory of backups stored
          --interval
            The interval of backup, format is: "a b c d e". 'a' means minute 
            (0 - 59), 'b' means hour (0 - 23), 'c' means day of month (1 - 
            31), 'd' means month (1 - 12), 'e' means day of week (0 - 6) 
            (Sunday=0), "*" means all
            Default: "0 0 * * *"

    dump      Dump graph to files
      Usage: dump [options]
        Options:
          --directory, -d
            Directory of graph schema/data, default is './{graphname}' in 
            local file system or '{fs.default.name}/{graphname}' in HDFS
          --formatter, -f
            Formatter to customize format of vertex/edge
            Default: JsonFormatter
          --log, -l
            Directory of log
            Default: ./logs
          --retry
            Retry times, default is 3
            Default: 3
          --split-size, -s
            Split size of shard
            Default: 1048576
          --thread-num, -T
            Threads number to use, default is Math.min(10, Math.max(4, CPUs / 
            2)) 
            Default: 0
          -D
            HDFS config parameters
            Syntax: -Dkey=value
            Default: {}

    restore      Restore graph schema/data. If directory is on HDFS, use -D to 
            set HDFS params if needed. For 
            example:-Dfs.default.name=hdfs://localhost:9000 
      Usage: restore [options]
        Options:
          --clean
            Whether to remove the directory of graph data after restored
            Default: false
          --directory, -d
            Directory of graph schema/data, default is './{graphname}' in 
            local file system or '{fs.default.name}/{graphname}' in HDFS
          --huge-types, -t
            Type of schema/data. Concat with ',' if more than one. Other types 
            include 'all' and 'schema'. 'all' means all vertices, edges and 
            schema. In other words, 'all' equals with 'vertex, edge, 
            vertex_label, edge_label, property_key, index_label'. 'schema' 
            equals with 'vertex_label, edge_label, property_key, index_label'.
            Default: [PROPERTY_KEY, VERTEX_LABEL, EDGE_LABEL, INDEX_LABEL, VERTEX, EDGE]
          --log, -l
            Directory of log
            Default: ./logs
          --retry
            Retry times, default is 3
            Default: 3
          --thread-num, -T
            Threads number to use, default is Math.min(10, Math.max(4, CPUs / 
            2)) 
            Default: 0
          -D
            HDFS config parameters
            Syntax: -Dkey=value
            Default: {}

    migrate      Migrate graph
      Usage: migrate [options]
        Options:
          --directory, -d
            Directory of graph schema/data, default is './{graphname}' in 
            local file system or '{fs.default.name}/{graphname}' in HDFS
          --graph-mode, -m
            Mode used when migrating to target graph, include: [RESTORING, 
            MERGING] 
            Default: RESTORING
            Possible Values: [NONE, RESTORING, MERGING, LOADING]
          --huge-types, -t
            Type of schema/data. Concat with ',' if more than one. Other types 
            include 'all' and 'schema'. 'all' means all vertices, edges and 
            schema. In other words, 'all' equals with 'vertex, edge, 
            vertex_label, edge_label, property_key, index_label'. 'schema' 
            equals with 'vertex_label, edge_label, property_key, index_label'.
            Default: [PROPERTY_KEY, VERTEX_LABEL, EDGE_LABEL, INDEX_LABEL, VERTEX, EDGE]
          --keep-local-data
            Whether to keep the local directory of graph data after restored
            Default: false
          --log, -l
            Directory of log
            Default: ./logs
          --retry
            Retry times, default is 3
            Default: 3
          --split-size, -s
            Split size of shard
            Default: 1048576
          --target-graph
            The name of target graph to migrate
            Default: hugegraph
          --target-password
            The password of target graph to migrate
          --target-timeout
            The timeout to connect target graph to migrate
            Default: 0
          --target-trust-store-file
            The trust store file of target graph to migrate
          --target-trust-store-password
            The trust store password of target graph to migrate
          --target-url
            The url of target graph to migrate
            Default: http://127.0.0.1:8081
          --target-user
            The username of target graph to migrate
          --thread-num, -T
            Threads number to use, default is Math.min(10, Math.max(4, CPUs / 
            2)) 
            Default: 0
          -D
            HDFS config parameters
            Syntax: -Dkey=value
            Default: {}

    deploy      Install HugeGraph-Server and HugeGraph-Studio
      Usage: deploy [options]
        Options:
        * -p
            Install path of HugeGraph-Server and HugeGraph-Studio
          -u
            Download url prefix path of HugeGraph-Server and HugeGraph-Studio
        * -v
            Version of HugeGraph-Server and HugeGraph-Studio

    start-all      Start HugeGraph-Server and HugeGraph-Studio
      Usage: start-all [options]
        Options:
        * -p
            Install path of HugeGraph-Server and HugeGraph-Studio
        * -v
            Version of HugeGraph-Server and HugeGraph-Studio

    clear      Clear HugeGraph-Server and HugeGraph-Studio
      Usage: clear [options]
        Options:
        * -p
            Install path of HugeGraph-Server and HugeGraph-Studio

    stop-all      Stop HugeGraph-Server and HugeGraph-Studio
      Usage: stop-all

    auth-backup      null
      Usage: auth-backup [options]
        Options:
          --directory
            Directory of auth information, default is 
            './{auth-backup-restore}' in local file system or 
            '{fs.default.name}/{auth-backup-restore}' in HDFS
          --retry
            Retry times, default is 3
            Default: 3
          --types, -t
            Type of auth data to restore and backup, concat with ',' if more 
            than one. 'all' means all auth information. In other words, 'all' 
            equals with 'user, group, target, belong, access'. In addition, 
            'belong' or 'access' can not backup or restore alone, if type 
            contains 'belong' then should contains 'user' and 'group'. If type 
            contains 'access' then should contains 'group' and 'target'.
            Default: [TARGET, GROUP, USER, ACCESS, BELONG]
          -D
            HDFS config parameters
            Syntax: -Dkey=value
            Default: {}

    auth-restore      null
      Usage: auth-restore [options]
        Options:
          --directory
            Directory of auth information, default is 
            './{auth-backup-restore}' in local file system or 
            '{fs.default.name}/{auth-backup-restore}' in HDFS
          --init-password
            Init user password, if restore type include 'user', please specify 
            the init-password of users.
            Default: <empty string>
          --retry
            Retry times, default is 3
            Default: 3
          --strategy
            The strategy needs to be chosen in the event of a conflict when 
            restoring. Valid strategies include 'stop' and 'ignore', default 
            is 'stop'. 'stop' means if there a conflict, stop restore. 
            'ignore' means if there a conflict, ignore and continue to 
            restore. 
            Default: STOP
            Possible Values: [STOP, IGNORE]
          --types, -t
            Type of auth data to restore and backup, concat with ',' if more 
            than one. 'all' means all auth information. In other words, 'all' 
            equals with 'user, group, target, belong, access'. In addition, 
            'belong' or 'access' can not backup or restore alone, if type 
            contains 'belong' then should contains 'user' and 'group'. If type 
            contains 'access' then should contains 'group' and 'target'.
            Default: [TARGET, GROUP, USER, ACCESS, BELONG]
          -D
            HDFS config parameters
            Syntax: -Dkey=value
            Default: {}

    help      Print usage
      Usage: help
3.10 Specific command example
1. gremlin statement
# Execute gremlin synchronously
./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph gremlin-execute --script 'g.V().count()'

# Execute gremlin asynchronously
./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph gremlin-schedule --script 'g.V().count()'
2. Show task status
./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph task-list

./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph task-list --limit 5

./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph task-list --status success
3. Set and show graph mode
./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph graph-mode-set -m RESTORING

./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph graph-mode-get

./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph graph-list
4. Cleanup Graph
./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph graph-clear -c "I'm sure to delete all data"
5. Backup Graph
./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph backup -t all --directory ./backup-test
6. Periodic Backup Graph
./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph schedule-backup -d ./backup --interval "*/2 * * * *"
7. Recovery Graph
# set graph mode
./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph graph-mode-set -m RESTORING

# recovery graph
./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph restore -t all --directory ./backup-test

# restore graph mode
./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph graph-mode-set -m NONE
8. Graph Migration
./bin/hugegraph --url http://127.0.0.1:8080 --graph hugegraph migrate --target-url http://127.0.0.1:8090 --target-graph hugegraph

2.7 - HugeGraph-Spark-Connector Quick Start

1 HugeGraph-Spark-Connector Overview

HugeGraph-Spark-Connector uses the Spark DataFrame API to write bulk data to HugeGraph. The current implementation provides vertex and edge writers.

Reading from HugeGraph is not implemented yet: the table only implements SupportsWrite, so spark.read.format(...) is not supported. The connector supports the CUSTOMIZE and PRIMARY_KEY vertex id strategies; the AUTOMATIC strategy is rejected.

2 Environment Requirements

  • Java 8+
  • Maven 3.6+
  • Spark 3.2.x (the module is built against Spark 3.2.2 with provided scope, so your Spark runtime must supply the Spark jars)
  • Scala 2.12 (built with Scala 2.12.11)

3 Building

3.1 Build without executing tests

git clone https://github.com/apache/hugegraph-toolchain.git
cd hugegraph-toolchain
mvn clean package -pl hugegraph-spark-connector -am -DskipTests -ntp

3.2 Build with default tests

mvn clean package -pl hugegraph-spark-connector -am -ntp

Both commands produce a fat jar at hugegraph-spark-connector/target/hugegraph-spark-connector-${revision}-jar-with-dependencies.jar (Spark itself is not bundled). Pass it to spark-submit --jars when you do not manage the dependency through Maven.

4 Usage

Add the dependency to pom.xml, replacing ${revision} with the release version you use:

<dependency>
    <groupId>org.apache.hugegraph</groupId>
    <artifactId>hugegraph-spark-connector</artifactId>
    <version>${revision}</version>
</dependency>

The format string must be the full class name org.apache.hugegraph.spark.connector.DataSource; the connector does not register a short name with Spark’s DataSourceRegister service loader. When HugeGraphServer has authentication enabled, add .option("username", ...) and .option("token", ...) to the examples below.

4.1 Schema Definition Example

If we have a graph, the schema is defined as follows:

schema.propertyKey("name").asText().ifNotExist().create()
schema.propertyKey("age").asInt().ifNotExist().create()
schema.propertyKey("city").asText().ifNotExist().create()
schema.propertyKey("weight").asDouble().ifNotExist().create()
schema.propertyKey("lang").asText().ifNotExist().create()
schema.propertyKey("date").asText().ifNotExist().create()
schema.propertyKey("price").asDouble().ifNotExist().create()

schema.vertexLabel("person")
        .properties("name", "age", "city")
        .useCustomizeStringId()
        .nullableKeys("age", "city")
        .ifNotExist()
        .create()

schema.vertexLabel("software")
        .properties("name", "lang", "price")
        .primaryKeys("name")
        .ifNotExist()
        .create()

schema.edgeLabel("knows")
        .sourceLabel("person")
        .targetLabel("person")
        .properties("date", "weight")
        .ifNotExist()
        .create()

schema.edgeLabel("created")
        .sourceLabel("person")
        .targetLabel("software")
        .properties("date", "weight")
        .ifNotExist()
        .create()

4.2 Vertex Sink (Scala)

val df = sparkSession.createDataFrame(Seq(
  Tuple3("marko", 29, "Beijing"),
  Tuple3("vadas", 27, "HongKong"),
  Tuple3("Josh", 32, "Beijing"),
  Tuple3("peter", 35, "ShangHai"),
  Tuple3("li,nary", 26, "Wu,han"),
  Tuple3("Bob", 18, "HangZhou"),
)) toDF("name", "age", "city")

df.show()

df.write
  .format("org.apache.hugegraph.spark.connector.DataSource")
  .option("host", "127.0.0.1")
  .option("port", "8080")
  .option("graph", "hugegraph")
  .option("data-type", "vertex")
  .option("label", "person")
  .option("id", "name")
  .option("batch-size", 2)
  .mode(SaveMode.Overwrite)
  .save()

4.3 Edge Sink (Scala)

val df = sparkSession.createDataFrame(Seq(
  Tuple4("marko", "vadas", "20160110", 0.5),
  Tuple4("peter", "Josh", "20230801", 1.0),
  Tuple4("peter", "li,nary", "20130220", 2.0)
)).toDF("source", "target", "date", "weight")

df.show()

df.write
  .format("org.apache.hugegraph.spark.connector.DataSource")
  .option("host", "127.0.0.1")
  .option("port", "8080")
  .option("graph", "hugegraph")
  .option("data-type", "edge")
  .option("label", "knows")
  .option("source-name", "source")
  .option("target-name", "target")
  .option("batch-size", 2)
  .mode(SaveMode.Overwrite)
  .save()

4.4 Vertex Sink with PRIMARY_KEY id strategy (Scala)

For a vertex label that uses primaryKeys(...), do not set the id option: the id is spliced from the primary key columns. Columns that are not part of the schema can be dropped with ignored-fields.

val df = sparkSession.createDataFrame(Seq(
  Tuple4("lop", "java", 328L, "ISBN978-7-107-18618-5"),
  Tuple4("ripple", "python", 199L, "ISBN978-7-100-13678-5"),
)).toDF("name", "lang", "price", "ISBN")

df.write
  .format("org.apache.hugegraph.spark.connector.DataSource")
  .option("host", "127.0.0.1")
  .option("port", "8080")
  .option("graph", "hugegraph")
  .option("data-type", "vertex")
  .option("label", "software")
  .option("ignored-fields", "ISBN")
  .option("batch-size", 2)
  .mode(SaveMode.Overwrite)
  .save()

4.5 Edge Sink with mixed id strategies (Scala)

source-name and target-name follow the id strategy of their own vertex label. Below, person uses a customized string id (one column) while software uses a primary key (its name column):

val df = sparkSession.createDataFrame(Seq(
  Tuple4("marko", "lop", "20171210", 0.5),
  Tuple4("Josh", "lop", "20091111", 0.4),
  Tuple4("peter", "ripple", "20171210", 1.0),
  Tuple4("vadas", "lop", "20171210", 0.2)
)).toDF("source", "name", "date", "weight")

df.write
  .format("org.apache.hugegraph.spark.connector.DataSource")
  .option("host", "127.0.0.1")
  .option("port", "8080")
  .option("graph", "hugegraph")
  .option("data-type", "edge")
  .option("label", "created")
  .option("source-name", "source") // customize id
  .option("target-name", "name")   // primary key
  .option("batch-size", 2)
  .mode(SaveMode.Overwrite)
  .save()

Note on save modes: SaveMode.Overwrite and SaveMode.Append both insert the rows. The overwrite path does not delete existing data from the graph first.

5 Configuration Parameters

Option keys are matched case-insensitively and trimmed. data-type and label are always required; source-name and target-name are required when data-type is edge; all other options have defaults.

5.1 Client Configs

Client Configs are used to configure hugegraph-client.

ParameterDefault ValueDescription
hostlocalhostAddress of HugeGraphServer. A bare host name or IP, or a full http:// / https:// prefix
port8080Port of HugeGraphServer
graphhugegraphGraph name
protocolhttpProtocol for sending requests to the server, optional http or https
usernamenullUsername of the current graph when HugeGraphServer enables permission authentication. When unset, the graph name is used as the username
tokennullToken of the current graph when HugeGraphServer has enabled authorization authentication
timeout60Timeout (seconds) for inserting results to return
max-connCPUS * 4The maximum number of HTTP connections between HugeClient and HugeGraphServer
max-conn-per-routeCPUS * 2The maximum number of HTTP connections for each route between HugeClient and HugeGraphServer
trust-store-filenullThe client’s certificate file path when the request protocol is https. When unset under https, the connector reads conf/hugegraph.truststore under the directory given by the JVM system property connector.home.path, which must then be set
trust-store-tokennullThe client’s certificate password when the request protocol is https. When unset under https, hugegraph is used

5.2 Graph Data Configs

Graph Data Configs describe how DataFrame columns map to vertices or edges.

ParameterDefault ValueDescription
data-typeRequired. Graph data type, must be vertex or edge
labelRequired. Label to which the vertex/edge data to be imported belongs
idSpecify a column as the id column of the vertex. When the vertex id policy is CUSTOMIZE, it is required; when the id policy is PRIMARY_KEY, it must be empty. The AUTOMATIC id policy is not supported
source-nameRequired when data-type is edge. Select certain columns of the input source as the id column of source vertex. When the id policy of the source vertex is CUSTOMIZE, a certain column must be specified as the id column of the vertex; when the id policy of the source vertex is PRIMARY_KEY, one or more columns must be specified for splicing the id of the generated vertex, that is, no matter which id strategy is used, this item is required. Multiple columns are separated by , (the delimiter option does not apply here)
target-nameRequired when data-type is edge. Specify certain columns as the id columns of target vertex, similar to source-name
selected-fieldsSelect some columns to insert, other unselected ones are not inserted, cannot exist at the same time as ignored-fields
ignored-fieldsIgnore some columns so that they do not participate in insertion, cannot exist at the same time as selected-fields
batch-size500The number of data items in each batch when importing data. Applied per Spark task: each partition writer flushes its buffer to the server once it holds this many vertices/edges, and again at commit for the remainder

5.3 Common Configs

Common Configs contains some common configurations.

ParameterDefault ValueDescription
delimiter,Separator of selected-fields and ignored-fields. source-name and target-name are always split on ,

6 Notes and Limitations

  • Each Spark write task opens its own HugeClient, switches the graph to LOADING mode before writing and sets it back to NONE at commit or abort.
  • Vertex ids are limited to 128 bytes (UTF-8). This applies to customized string ids and to ids spliced from primary keys.
  • The AUTOMATIC vertex id strategy is not supported; the write fails with an IllegalArgumentException when the writer is created.
  • Properties with SET or LIST cardinality are not supported yet; only SINGLE cardinality values are converted.
  • Date properties: string values must use the format yyyy-MM-dd HH:mm:ss and are parsed in the GMT+8 time zone; numeric values are treated as epoch milliseconds.
  • Boolean properties given as strings accept true, 1, yes, y and false, 0, no, n (case-insensitive).
  • Rows whose customized string id, or any primary key value, is an empty string are skipped. A null id or primary key value raises an error instead.

7 License

The same as HugeGraph, hugegraph-spark-connector is also licensed under Apache 2.0 License.

3 - HugeGraph-AI

hugegraph-ai provides Python clients for HugeGraph, graph machine learning tools, and LLM tools for knowledge graph construction and GraphRAG applications.

Apache License 2.0 · Ask DeepWiki

Modules

  • hugegraph-llm: knowledge graph construction, GraphRAG, and natural-language graph queries.
  • hugegraph-ml: reads graph data from HugeGraph and runs graph learning models.
  • hugegraph-python-client: a Python SDK for managing schemas and graph data and running Gremlin queries.
  • vermeer-python-client: a Python SDK for the Vermeer graph computing service.

The repository uses a uv workspace whose members are hugegraph-llm and hugegraph-python-client. hugegraph-ml and vermeer-python-client are editable path dependencies rather than workspace members. The current repository version is 1.7.0.

Requirements

  • HugeGraph-LLM: Python 3.10 or 3.11 (>=3.10,<3.12)
  • HugeGraph-ML: Python 3.10 or later
  • HugeGraph Python client and Vermeer Python client: Python 3.9 or later
  • uv 0.7 or later
  • HugeGraph Server 1.3 or later (1.5 or later recommended)

Optional Dependency Groups

The root project declares one extra per module plus a few combined ones:

ExtraInstalls
llmhugegraph-llm
mlhugegraph-ml
python-clienthugegraph-python-client
vermeervermeer-python-client
devpytest, pytest-cov, coverage, pylint, ruff, mypy, ty, pre-commit
nk-llmhugegraph-llm, hugegraph-python-client, and Nuitka for the compiled image
allall four module packages

hugegraph-llm itself declares a vectordb extra that adds pymilvus and qdrant-client.

Deploy with Docker Compose

The repository includes a Compose file that starts both HugeGraph Server and the RAG service:

git clone https://github.com/apache/hugegraph-ai.git
cd hugegraph-ai
cp docker/env.template docker/.env
# Edit docker/.env and set PROJECT_PATH to the absolute path of this repository
touch hugegraph-llm/.env
cd docker
docker compose -f docker-compose-network.yml up -d

Default addresses:

  • HugeGraph Server: http://localhost:8080
  • RAG service and Web UI: http://localhost:8001

Start the RAG Service from Source

git clone https://github.com/apache/hugegraph-ai.git
cd hugegraph-ai
uv sync --extra llm
source .venv/bin/activate
cd hugegraph-llm
python -m hugegraph_llm.demo.rag_demo.app

uv sync creates .venv at the repository root. Do not create a separate environment under hugegraph-llm, because doing so can bypass the dependencies locked by the workspace.

Install ML Dependencies

cd hugegraph-ai
uv sync --extra ml
source .venv/bin/activate
cd hugegraph-ml/src

Example scripts are under hugegraph-ml/src/hugegraph_ml/examples/.

Next Steps

3.1 - HugeGraph-LLM

HugeGraph-LLM connects graph databases with large language models for knowledge graph construction, GraphRAG, and natural-language graph queries. Its demo service hosts the Gradio UI and FastAPI endpoints in the same process and listens on port 8001 by default.

Requirements

AI-generated project documentation: Ask DeepWiki

  • Python 3.10 or 3.11 (>=3.10,<3.12)
  • uv 0.7 or later
  • HugeGraph Server 1.3 or later (1.5 or later recommended)

Deploy with Docker Compose

Prepare the environment files from the HugeGraph-AI repository root:

git clone https://github.com/apache/hugegraph-ai.git
cd hugegraph-ai
cp docker/env.template docker/.env
# Edit docker/.env and set PROJECT_PATH to the absolute path of this repository
touch hugegraph-llm/.env
cd docker
docker compose -f docker-compose-network.yml up -d
docker compose -f docker-compose-network.yml ps

After startup, HugeGraph Server is available at http://localhost:8080, and the RAG service and Web UI are available at http://localhost:8001.

The Compose file mounts ${PROJECT_PATH}/hugegraph-llm/.env into the container at /home/work/hugegraph-llm/.env, so the file has to exist before the container starts. The resource directory hugegraph-llm/src/hugegraph_llm/resources can be mounted the same way; the mount is commented out by default.

Container Images

ImageBuilt fromContents
hugegraph/ragdocker/Dockerfile.llmPython 3.10 runtime with the source tree, started with python -m hugegraph_llm.demo.rag_demo.app --host 0.0.0.0 --port 8001
hugegraph/rag-bindocker/Dockerfile.nkNuitka-compiled binary built from the nk-llm extra, started with ./app.dist/app.bin

Both images expose port 8001, run as the non-root user work, declare a volume for hugegraph-llm/src/hugegraph_llm/resources, and use curl -f http://localhost:8001/ as their health check.

scripts/build_llm_image.sh builds docker/Dockerfile.llm and tags the result hugegraph/graphrag:1.7.0.

Deploy on Kubernetes

docker/charts/hg-llm is a Helm chart for the RAG service. It deploys the hugegraph/graphrag image and, by default, publishes a NodePort service that maps node port 8039 and service port 8080 onto container port 8001. The release name is fixed to hg-llm-service. Ingress and horizontal pod autoscaling are present but disabled by default.

The chart still defaults image.tag to v0.0.1, so set --set image.tag=1.7.0 or edit values.yaml to match the tag you built.

The chart ships the .env and prompt YAML mounts commented out in values.yaml. To supply your own configuration, create the two config maps and then uncomment the matching volumes and volumeMounts blocks:

kubectl create configmap hugegraph-llm-env --from-file=/path/to/.env
kubectl create configmap hugegraph-llm-prompt-config --from-file=/path/to/config_prompt.yaml

Start from Source

Install dependencies through the workspace at the repository root:

git clone https://github.com/apache/hugegraph-ai.git
cd hugegraph-ai
uv sync --extra llm
source .venv/bin/activate
cd hugegraph-llm
python -m hugegraph_llm.demo.rag_demo.app

To use a custom address and port:

python -m hugegraph_llm.demo.rag_demo.app \
  --host 127.0.0.1 \
  --port 18001

Set HG_DEV_RELOAD=1 to start uvicorn with auto-reload during development.

The service stores model, HugeGraph, and login settings in hugegraph-llm/.env. Prompts are stored separately in hugegraph-llm/src/hugegraph_llm/resources/demo/config_prompt.yaml. The configuration code creates missing files with default values.

The .env location is resolved in this order: HUGEGRAPH_LLM_ENV_PATH if it is set, then hugegraph-llm/.env when the package runs from a source checkout, then .env in the current working directory.

Main Capabilities

Build RAG Indexes

The first Web UI tab splits text into a chunk vector index, extracts vertices and edges according to a schema, writes the graph to HugeGraph, and updates the vertex vector index. Input can be typed into the text tab or uploaded through the file tab, which accepts .txt, .docx, and .pdf files and allows selecting several at once. Encrypted PDFs and scanned PDFs without an extractable text layer are rejected.

The schema can be inline JSON or the name of an existing graph. Through the REST API, a graph name requires a matching client_config.graph; inline JSON neither connects to HugeGraph nor accepts client_config.

The tab also carries two generators. Graph Schema Generator derives a schema from query examples plus a few-shot example. Graph Extraction Prompt Generator writes an extraction prompt from a described scenario and a selected reference example. A Graph Extraction Split Type dropdown chooses document, paragraph, or sentence granularity before extraction.

GraphRAG

The query pipeline can combine direct LLM answers, chunk-vector retrieval, and graph retrieval. Graph retrieval first extracts keywords and matches vertices, then attempts Text2Gremlin. If generation or execution fails, it can fall back to predefined graph traversals. Request parameters control result limits, vector distance thresholds, template counts, and reranking.

The same tab has a batch back-testing panel that reads questions from an .xlsx or .csv file, answers each one, and returns a downloadable file. A template file is offered for download next to the upload control.

Knowledge graph builder

Text2Gremlin

POST /text2gremlin generates Gremlin from natural language, the graph schema, and optional examples. A custom prompt must retain {query}, {schema}, {example}, and {vertices}.

The matching UI tab can first build the example vector index from a .json or .csv file of question and Gremlin pairs. The bundled resources/demo/text2gremlin.csv is used when no file is supplied.

Graph and Admin Tools

The Graph Tools tab runs a Gremlin query directly, triggers a manual graph backup, and can initialize demo data in HugeGraph. The Admin Tools tab shows the last lines of logs/llm-server.log behind an ADMIN_TOKEN prompt, and can refresh or clear that file.

Two background tasks run for the lifetime of the process: a cron job that backs up the graph every day at 01:00, and a task that keeps vertex-id embeddings up to date.

Models and Vector Backends

Chat, information extraction, and Text2Gremlin can independently use an OpenAI-compatible endpoint, Ollama, or LiteLLM. The embedding model is configured separately and supports the same three providers. Reranking supports Cohere and SiliconFlow.

FAISS is the default vector index. CUR_VECTOR_INDEX selects Faiss, Milvus, or Qdrant, and the same choice is available in the 5. Set up the vector engine. panel of the Web UI. Milvus and Qdrant require the optional dependencies:

cd hugegraph-ai
uv sync --package hugegraph-llm --extra vectordb

See the workflow guide, the configuration reference, and the REST API for details.

Programmatic Use

The former RAGPipeline and KgBuilder classes were replaced by a pipeline scheduler. Call a flow by name through SchedulerSingleton:

from hugegraph_llm.flows.scheduler import SchedulerSingleton

scheduler = SchedulerSingleton.get_instance()
res = scheduler.schedule_flow(
    "rag_graph_only",
    query="Tell me about Al Pacino.",
    graph_only_answer=True,
    vector_only_answer=False,
    raw_answer=False,
    gremlin_tmpl_num=-1,
    gremlin_prompt=None,
)
print(res.get("graph_only_answer"))

The registered flow names are rag_raw, rag_vector_only, rag_graph_only, rag_graph_vector, text2gremlin, build_examples_index, build_vector_index, graph_extract, import_graph_data, update_vid_embeddings, get_graph_index_info, build_schema, and prompt_generate. schedule_stream_flow is the async streaming variant.

Development Checks

Install the module and the development tools from the repository root, then run the checks that mirror CI:

cd hugegraph-ai
uv sync --extra llm --extra dev
uv run ruff format --check .
uv run ruff check .

cd hugegraph-llm
SKIP_EXTERNAL_SERVICES=true uv run pytest src/tests/config/ src/tests/document/ src/tests/middleware/ \
  src/tests/operators/ src/tests/models/ src/tests/indices/ src/tests/test_utils.py -v --tb=short
SKIP_EXTERNAL_SERVICES=true uv run pytest src/tests/integration/test_graph_rag_pipeline.py \
  src/tests/integration/test_kg_construction.py src/tests/integration/test_rag_pipeline.py -v --tb=short

Git hooks are available through pre-commit:

cd hugegraph-ai
pre-commit install
pre-commit run --all-files

3.2 - HugeGraph-ML

HugeGraph-ML reads graph data from HugeGraph and converts it to DGL graphs for tasks such as node embedding, node classification, graph classification, link prediction and fraud detection. Model implementations are under hugegraph-ml/src/hugegraph_ml/models/.

Requirements

  • Python 3.10 or later
  • HugeGraph Server 1.0 or later; 1.5 or later is recommended
  • uv 0.7 or later

All server access goes through hugegraph-python-client (the pyhugegraph package) from the same repository. HugeGraph2DGL pulls vertices and edges over the Gremlin endpoint with g.V().hasLabel(...) and g.E().hasLabel(...), and the dataset importers write through the schema and batch vertex/edge APIs in batches of 500.

The ML stack is version pinned at the repository root under [tool.uv] constraint-dependencies:

PackagePin
torch==2.2.0
dgl~=2.1.0
ogb~=1.3.6
torchdata~=0.7.0
catboost~=1.2.3
category-encoders~=2.6.3
numpy~=1.24.4
pandas~=2.2.3

Those pins install CPU builds. Every task accepts a gpu argument that defaults to -1, meaning CPU; pass a device index only after installing CUDA builds of torch and dgl yourself.

Installation

git clone https://github.com/apache/hugegraph-ai.git
cd hugegraph-ai
uv sync --extra ml
source .venv/bin/activate
cd hugegraph-ml/src

HugeGraph-ML is a path dependency of the root project but is not a uv workspace member. Select the ml extra at the repository root instead of creating another lock file in the subdirectory.

Implemented Models

Every module below lives in hugegraph-ml/src/hugegraph_ml/models/. models/__init__.py re-exports nothing, so import from the module file directly.

ModelModuleEntry classUsed forPaper
AGNNagnn.pyAGNNNode classification1803.03735
APPNPappnp.pyAPPNPNode classification1810.05997
ARMAarma.pyARMA4NCNode classification1901.01343
BGNNbgnn.pyBGNNPredictorGradient boosting over node features combined with a GNN; the bundled example runs regression2101.08543
BGRLbgrl.pyBGRLSelf-supervised node embedding2102.06514
CARE-GNNcare_gnn.pyCAREGNNFraud detection2008.08692
Cluster-GCNcluster_gcn.pySAGENode classification with subgraph sampling1905.07953
C&Scorrect_and_smooth.pyMLP, CorrectAndSmooth, LabelPropagationCorrecting and smoothing base predictions2010.13993
DAGNNdagnn.pyDAGNNNode classification2007.09296
DeeperGCNdeepergcn.pyDeeperGCNNode classification with edge features2006.07739
DGIdgi.pyDGISelf-supervised node embedding1809.10341
DiffPooldiffpool.pyDiffPoolGraph classification1806.08804
GATNEgatne.pyDGLGATNEHeterogeneous network embedding1905.01669
GINgin_global_pool.pyGINGraph classification
GRACEgrace.pyGRACESelf-supervised node embedding2006.04131
GRANDgrand.pyGRANDNode classification2005.11079
JKNetjknet.pyJKNetNode classification1806.03536
MLPmlp.pyMLPClassifierDownstream classifier over learned embeddings
P-GNNpgnn.pyPGNNLink predictionyou19b
SEALseal.pyDGCNN, SEALDataLink prediction1802.09691

GIN accepts pooling values sum (default), mean, max, global_attention and set2set.

Reading Graph Data

HugeGraph2DGL in hugegraph-ml/src/hugegraph_ml/data/hugegraph2dgl.py opens a PyHugeClient and converts query results into DGL objects:

from hugegraph_ml.data.hugegraph2dgl import HugeGraph2DGL

hg2d = HugeGraph2DGL(
    url="http://127.0.0.1:8080",
    graph="hugegraph",
    user="",
    pwd="",
    graphspace=None,
)
MethodReturnsNotes
convert_graph(vertex_label, edge_label, feat_key="feat", label_key="label", mask_keys=None)dgl.DGLGraphmask_keys falls back to ["train_mask", "val_mask", "test_mask"]
convert_hetero_graph(vertex_labels, edge_labels, feat_key="feat", label_key="label", mask_keys=None)DGL heterographTakes lists of labels
convert_graph_dataset(graph_vertex_label, vertex_label, edge_label, feat_key="feat", label_key="label")HugeGraphDatasetFills info with n_graphs, max_n_nodes, n_feat_dim, n_classes
convert_graph_nx(vertex_label, edge_label)networkx.GraphUsed by P-GNN
convert_graph_with_edge_feat(vertex_label, edge_label, node_feat_key="feat", edge_feat_key="edge_feat", label_key="label", mask_keys=None)dgl.DGLGraphAlso fills edata["feat"]
convert_graph_ogb(vertex_label, edge_label, split_label)(dgl.DGLGraph, split_edge)Used by SEAL
convert_hetero_graph_bgnn(vertex_labels, edge_labels, feat_key="feat", label_key="class", cat_key="cat_features", mask_keys=None)DGL heterographUsed by BGNN

Node features land in ndata["feat"], labels in ndata["label"] and each mask in ndata[<mask key>]. NodeEmbed requires feat only; NodeClassify, NodeClassifyWithEdge and NodeClassifyWithSample require feat, label, train_mask, val_mask and test_mask and raise ValueError when one is missing.

Importing Sample Datasets

hugegraph_ml.utils.dgl2hugegraph_utils writes DGL, OGB and NetworkX datasets into HugeGraph so the conversion layer has something to read. Every function takes the same url, graph, user, pwd and graphspace arguments as HugeGraph2DGL, and most upper-case the dataset name before matching it.

FunctionAccepted datasetsLabels created
import_graph_from_dglCORA, CITESEER, PUBMED<NAME>_vertex, <NAME>_edge
import_graphs_from_dglMUTAG, COLLAB, NCI1, PROTEINS, PTC, ENZYMES, DD<NAME>_graph_vertex, <NAME>_vertex, <NAME>_edge
import_hetero_graph_from_dglACM<NAME>_<ntype>_v, <NAME>_<etype>_e
import_hetero_graph_from_dgl_no_featAMAZONGATNE<NAME>_<ntype>_v, <NAME>_<etype>_e
import_hetero_graph_from_dgl_bgnnAVAZU<NAME>_<ntype>_v, <NAME>_<etype>_e
import_graph_from_nxCAVEMAN<NAME>_vertex, <NAME>_edge
import_graph_from_dgl_with_edge_featCORA, CITESEER, PUBMED<NAME>_edge_feat_vertex, <NAME>_edge_feat_edge
import_graph_from_ogbogbl-collab, matched without upper-casing<NAME>_vertex, <NAME>_edge
import_split_edge_from_ogbogbl-collab, matched without upper-casing<NAME>_split_edge

Any other name raises ValueError("dataset not supported"). import_split_edge_from_ogb additionally requires the idx_to_vertex_id mapping and a max_nodes cap returned by the vertex import.

clear_all_data() drops every vertex and edge in the target graph. The test fixture calls it, loads CORA, MUTAG and ACM, and calls it again on teardown.

AMAZONGATNE and AVAZU are not fetched automatically. Their archive URLs are recorded in comments above import_hetero_graph_from_dgl_no_feat and import_hetero_graph_from_dgl_bgnn.

Tasks

Task classes live in hugegraph-ml/src/hugegraph_ml/tasks/. Each one takes the converted graph and a model instance.

ClassModuleEntry points
NodeEmbednode_embed.pytrain_and_embed(add_self_loop=True, lr=1e-3, weight_decay=0, n_epochs=200, patience=inf, gpu=-1) returns the graph with ndata["feat"] replaced by the embedding
NodeClassifynode_classify.pytrain(lr, weight_decay, n_epochs, patience, early_stopping_monitor, gpu) then evaluate(), which returns {"accuracy": ..., "loss": ...}
NodeClassifyWithEdgenode_classify_with_edge.pySame shape, for models that also read edata["feat"]
NodeClassifyWithSamplenode_classify_with_sample.pyCluster-GCN style training on ClusterGCNSampler partitions; runs on CPU and takes no gpu argument
GraphClassifygraph_classify.pytrain(batch_size=20, lr, weight_decay, n_epochs, patience, early_stopping_monitor, clip=2.0, gpu) over a HugeGraphDataset, split 70/20/10
DetectorCaregnnfraud_detector_caregnn.pyCARE-GNN training; evaluate() reports recall and ROC AUC and reads ndata["feature"] rather than ndata["feat"]
HeteroSampleEmbedGATNEhetero_sample_embed_gatne.pytrain_and_embed(lr=1e-3, n_epochs=200, gpu=-1)
LinkPredictionPGNNlink_prediction_pgnn.pytrain(lr, weight_decay, n_epochs, gpu)
LinkPredictionSeallink_prediction_seal.pyThe constructor calls data_prepare() itself, then train(lr=1e-3, n_epochs=200, gpu=-1)

patience defaults to float("inf"). EarlyStopping in utils/early_stopping.py monitors either loss or accuracy, keeps a copy of the best weights and restores them when training stops.

Runnable Examples

Scripts sit in hugegraph-ml/src/hugegraph_ml/examples/. From hugegraph-ml/src, run one with:

python ./hugegraph_ml/examples/dgi_example.py

Each script also exposes a function of the same name, so it can be imported and called with a smaller epoch count.

ScriptModelTaskReads
agnn_example.pyAGNNNodeClassifyCORA_vertex, CORA_edge
appnp_example.pyAPPNPNodeClassifyCORA_vertex, CORA_edge
arma_example.pyARMA4NCNodeClassifyCORA_vertex, CORA_edge
bgnn_example.pyBGNNPredictorIts own fit()AVAZU__N_v, AVAZU__E_e
bgrl_example.pyBGRLNodeEmbed, NodeClassifyCORA_vertex, CORA_edge
care_gnn_example.pyCAREGNNDetectorCaregnnAMAZON_user_v plus AMAZON_net_upu_e, AMAZON_net_usu_e, AMAZON_net_uvu_e
cluster_gcn_example.pySAGENodeClassifyWithSampleCORA_vertex, CORA_edge
correct_and_smooth_example.pyMLP from correct_and_smoothNodeClassifyCORA_vertex, CORA_edge
dagnn_example.pyDAGNNNodeClassifyCORA_vertex, CORA_edge
deepergcn_example.pyDeeperGCNNodeClassifyWithEdgeCORA_vertex, CORA_edge through convert_graph_with_edge_feat
dgi_example.pyDGINodeEmbed, NodeClassifyCORA_vertex, CORA_edge
diffpool_example.pyDiffPoolGraphClassifyMUTAG_graph_vertex, MUTAG_vertex, MUTAG_edge
gatne_example.pyDGLGATNEHeteroSampleEmbedGATNEAMAZONGATNE__N_v, AMAZONGATNE_1_e, AMAZONGATNE_2_e
gin_example.pyGINGraphClassifyMUTAG_graph_vertex, MUTAG_vertex, MUTAG_edge
grace_example.pyGRACENodeEmbed, NodeClassifyCORA_vertex, CORA_edge
grand_example.pyGRANDNodeClassifyCORA_vertex, CORA_edge
jknet_example.pyJKNetNodeClassifyCORA_vertex, CORA_edge
pgnn_example.pyPGNNLinkPredictionPGNNCAVEMAN_vertex, CAVEMAN_edge
seal_example.pyDGCNNLinkPredictionSealogbl-collab_vertex, ogbl-collab_edge, ogbl-collab_split_edge

DGI Node Embedding Example

First import DGL’s Cora dataset into HugeGraph. The name is upper-cased before use, so cora and CORA both produce the CORA_vertex and CORA_edge labels:

from hugegraph_ml.utils.dgl2hugegraph_utils import import_graph_from_dgl

import_graph_from_dgl("cora")

Read the graph and train DGI:

from hugegraph_ml.data.hugegraph2dgl import HugeGraph2DGL
from hugegraph_ml.models.dgi import DGI
from hugegraph_ml.models.mlp import MLPClassifier
from hugegraph_ml.tasks.node_classify import NodeClassify
from hugegraph_ml.tasks.node_embed import NodeEmbed

hg2d = HugeGraph2DGL()
graph = hg2d.convert_graph(vertex_label="CORA_vertex", edge_label="CORA_edge")

embed_model = DGI(n_in_feats=graph.ndata["feat"].shape[1])
embed_task = NodeEmbed(graph=graph, model=embed_model)
embedded_graph = embed_task.train_and_embed(
    add_self_loop=True, n_epochs=300, patience=30
)

classifier = MLPClassifier(
    n_in_feat=embedded_graph.ndata["feat"].shape[1],
    n_out_feat=embedded_graph.ndata["label"].unique().shape[0],
)
classify_task = NodeClassify(graph=embedded_graph, model=classifier)
classify_task.train(lr=1e-3, n_epochs=400, patience=40)
print(classify_task.evaluate())

evaluate() returns a dictionary such as {'accuracy': 0.82, 'loss': 0.5714246034622192}. The complete script is hugegraph-ml/src/hugegraph_ml/examples/dgi_example.py.

GRAND Node Classification Example

from hugegraph_ml.data.hugegraph2dgl import HugeGraph2DGL
from hugegraph_ml.models.grand import GRAND
from hugegraph_ml.tasks.node_classify import NodeClassify

hg2d = HugeGraph2DGL()
graph = hg2d.convert_graph(vertex_label="CORA_vertex", edge_label="CORA_edge")
model = GRAND(
    n_in_feats=graph.ndata["feat"].shape[1],
    n_out_feats=graph.ndata["label"].unique().shape[0],
)
task = NodeClassify(graph, model)
task.train(lr=1e-2, weight_decay=5e-4, n_epochs=2000, patience=100)
print(task.evaluate())

GRAND returns a list of logits per augmentation sample, and NodeClassify masks each element of that list before computing the loss. The complete script is hugegraph-ml/src/hugegraph_ml/examples/grand_example.py.

Troubleshooting

  • Connection failures: check the HugeGraph Server address, port, and credentials.
  • Schema mismatches: the examples use CORA_vertex and CORA_edge; pass the actual labels for your own data.
  • ValueError: Graph is missing required node attribute ...: the node classification tasks need feat, label, train_mask, val_mask and test_mask in ndata. Import a dataset that carries masks, or pass your own mask_keys to convert_graph.
  • ValueError: dataset not supported: the importer only accepts the names in the table above, and import_graph_from_ogb matches ogbl-collab without upper-casing.
  • DGL or PyTorch import failures: rerun uv sync --extra ml from the repository root and confirm that Python comes from the root .venv.
  • bgrl_example.py currently fails on import: it asks for MLP_Predictor from hugegraph_ml.models.bgrl, but that module defines the class as MLPPredictor.
  • care_gnn_example.py reads AMAZON_user_v and the three AMAZON_net_*_e edge labels. No bundled importer creates them, so load that dataset yourself before running the script.

3.3 - HugeGraph-LLM Workflow

This page explains the processing flow in the HugeGraph-LLM Web UI. See HugeGraph-LLM for startup instructions.

0. Configuration Panel

Above the tabs sits a collapsible configuration panel with five sections: 1. Set up the HugeGraph server., 2. Set up the LLM., 3. Set up the Embedding., 4. Set up the Reranker., and 5. Set up the vector engine.. Each section has its own apply button, and applying a change writes the supported fields back to .env. The header also shows the current prompt language.

1. Build RAG Indexes

The first tab splits documents into a chunk vector index. It also extracts vertices and edges according to a schema, writes them to HugeGraph, and maintains a vertex vector index.

flowchart TD
    A[Input document] --> B[Split text]
    B --> C[Generate chunk vectors]
    C --> D[Write vector index]
    B --> E[LLM extracts vertices and edges from schema]
    E --> F[Write to HugeGraph]
    F --> G[Update vertex vector index]

Input comes from either the text sub-tab or the file sub-tab. Uploads accept .txt, .docx, and .pdf, and several files can be selected at once.

Common operations are Import into Vector, Extract Graph Data (1), Load into GraphDB (2), and Update Vid Embedding. Load into GraphDB (2) also refreshes the vertex vector index, so the separate Update Vid Embedding step is only needed when the graph already held data. The Graph Extraction Split Type dropdown next to these buttons chooses document, paragraph, or sentence. document keeps the whole input as one unit; the other two split long documents before extraction.

The page can also inspect or clear chunk indexes, vertex indexes, and graph data. Clearing removes existing data, so first confirm that the current graph and indexes are not still used by other queries.

Two collapsed helpers sit below the main controls:

  • Graph Schema Generator takes query examples and a few-shot example and produces a schema for the Graph Schema field.
  • Graph Extraction Prompt Generator takes an expected scenario, such as social relationships or a financial knowledge graph, and a selected reference example, and produces a Graph Extract Prompt Header.

2. GraphRAG Queries

The second tab can answer directly with the LLM, use only chunk-vector retrieval, use only graph retrieval, or combine graph and vector retrieval.

flowchart TD
    Q[Question] --> V[Query chunk vector index]
    Q --> K[Extract keywords]
    K --> M[Match graph vertices]
    M --> T[Generate and execute Gremlin]
    T -->|Failure| B[Fallback to BFS graph traversal]
    T --> R[Prepare graph results]
    B --> R
    V --> S[Merge and rerank]
    R --> S
    S --> A[Generate answer]

Graph retrieval first matches HugeGraph vertices exactly by keyword and then uses vector similarity if no exact match exists. The matched vertices are passed to Text2Gremlin. If generation or execution fails, the pipeline can fall back to a predefined traversal.

Template Num controls how Text2Gremlin participates in graph retrieval:

  • A negative value skips Text2Gremlin entirely, so graph retrieval goes straight to the predefined traversal.
  • 0 generates Gremlin without any examples (zero-shot).
  • A positive value retrieves that many similar examples from the example index and uses the template-guided result. The example count is clamped to the range 0 to 10.

Other controls on this tab are Rerank method (bleu or reranker), Graph Ratio, Near neighbor first, and Query related information, plus editable Query Prompt and Keywords Extraction Prompt fields.

Below the single-question panel is a batch back-testing panel. Upload an .xlsx or .csv file of questions, set Max Lines To Show, and click Generate Answer (Batch). The answers appear in a preview table and can be downloaded as a file. A template file is offered next to the upload control.

3. Text2Gremlin

The third tab has two parts. The upper part builds the example vector index from a .json or .csv file of question and Gremlin pairs; the bundled resources/demo/text2gremlin.csv is used when no file is uploaded.

The lower part reads the graph schema, retrieves similar natural-language and Gremlin examples, fills the prompt with the question, schema, examples, and matched vertices, then generates Gremlin and optionally executes it. Number of refer examples sets how many examples are retrieved, from 0 to 10, and defaults to 2. The results appear in four fields: Gremlin with a template, Gremlin without a template, and the execution output for each.

RAG query scope selector

A custom prompt must contain {query}, {schema}, {example}, and {vertices}. The REST API rejects a request if any placeholder is missing.

4. Graph and Administration Tools

Graph Tools runs a Gremlin query directly against the configured graph, triggers a manual graph backup, and can initialize demo data in HugeGraph through a beta action. A background job also backs up the graph every day at 01:00, and a second background task keeps vertex-id embeddings up to date while the process runs.

Admin Tools is password protected. Entering the configured ADMIN_TOKEN reveals the tail of logs/llm-server.log, which refreshes every 60 seconds, along with buttons to refresh or clear it. Access is refused while ADMIN_TOKEN is empty or still set to the placeholder xxxx.

When ENABLE_LOGIN=True, the Web UI asks for basic credentials with the fixed user name rag and USER_TOKEN as the password, and the REST API requires USER_TOKEN as a Bearer token. The log endpoint additionally requires a separately configured, secure ADMIN_TOKEN.

Keywords extracted in the RAG UI

5. Prompt Language

Set LANGUAGE=EN or LANGUAGE=CN in hugegraph-llm/.env, then restart the service. This selects the language of built-in prompts; it does not translate input documents and is not a field in the /rag request body.

6. REST Calls

The Web UI and REST API use the same pipeline. For application integration, use /rag, /rag/graph, /graph/extract, and /text2gremlin; see the REST API for request formats.

3.4 - Configuration Reference

HugeGraph-LLM reads runtime settings from hugegraph-llm/.env. Prompts are stored separately in hugegraph-llm/src/hugegraph_llm/resources/demo/config_prompt.yaml and are not written to .env.

The .env path is resolved in this order:

  1. HUGEGRAPH_LLM_ENV_PATH, if that environment variable is set. A leading ~ is expanded.
  2. hugegraph-llm/.env, when the package runs from a source checkout.
  3. .env in the current working directory, for an installed package.

Create or update the files from configuration-class defaults with:

cd hugegraph-ai/hugegraph-llm
python -m hugegraph_llm.config.generate --update

--update is on by default, so running the module without arguments does the same thing. The command writes the HugeGraph, admin, LLM, and index settings, then regenerates the prompt YAML. If .env already exists, it asks for confirmation before overwriting.

.env contains keys and passwords. Do not commit it to version control.

Basic Options

SettingDefaultDescription
LANGUAGEENPrompt language: EN or CN
CHAT_LLM_TYPEopenaiAnswer model: openai, litellm, or ollama/local
EXTRACT_LLM_TYPEopenaiInformation extraction model; same choices as above
TEXT2GQL_LLM_TYPEopenaiText2Gremlin model; same choices as above
EMBEDDING_TYPEopenaiEmbedding model; same choices as above, or empty
RERANKER_TYPEemptycohere or siliconflow
KEYWORD_EXTRACT_TYPEllmllm, textrank, or hybrid
WINDOW_SIZE3TextRank window size, from 1 to 10
HYBRID_LLM_WEIGHTS0.5Weight of LLM results in hybrid mode, from 0 to 1

OpenAI-Compatible APIs

Chat, extraction, and Text2Gremlin can use different endpoints, keys, and models.

PurposeAPI baseKeyModelDefault maximum tokens
AnswerOPENAI_CHAT_API_BASEOPENAI_CHAT_API_KEYOPENAI_CHAT_LANGUAGE_MODELOPENAI_CHAT_TOKENS=8192
ExtractionOPENAI_EXTRACT_API_BASEOPENAI_EXTRACT_API_KEYOPENAI_EXTRACT_LANGUAGE_MODELOPENAI_EXTRACT_TOKENS=256
Text2GremlinOPENAI_TEXT2GQL_API_BASEOPENAI_TEXT2GQL_API_KEYOPENAI_TEXT2GQL_LANGUAGE_MODELOPENAI_TEXT2GQL_TOKENS=4096
EmbeddingOPENAI_EMBEDDING_API_BASEOPENAI_EMBEDDING_API_KEYOPENAI_EMBEDDING_MODELNot applicable

The default API base is https://api.openai.com/v1. The default language model for all three tasks is gpt-4.1-mini, and the default embedding model is text-embedding-3-small.

OPENAI_BASE_URL and OPENAI_API_KEY provide general fallback values. Embeddings also support OPENAI_EMBEDDING_BASE_URL and OPENAI_EMBEDDING_API_KEY as fallback values.

LiteLLM

PurposeAPI baseKeyModelDefault maximum tokens
AnswerLITELLM_CHAT_API_BASELITELLM_CHAT_API_KEYLITELLM_CHAT_LANGUAGE_MODELLITELLM_CHAT_TOKENS=8192
ExtractionLITELLM_EXTRACT_API_BASELITELLM_EXTRACT_API_KEYLITELLM_EXTRACT_LANGUAGE_MODELLITELLM_EXTRACT_TOKENS=256
Text2GremlinLITELLM_TEXT2GQL_API_BASELITELLM_TEXT2GQL_API_KEYLITELLM_TEXT2GQL_LANGUAGE_MODELLITELLM_TEXT2GQL_TOKENS=4096
EmbeddingLITELLM_EMBEDDING_API_BASELITELLM_EMBEDDING_API_KEYLITELLM_EMBEDDING_MODELNot applicable

The default language model is openai/gpt-4.1-mini, and the default embedding model is openai/text-embedding-3-small. Model names generally use the provider/model form; supported values depend on the LiteLLM service.

Ollama

PurposeHostPortModel
AnswerOLLAMA_CHAT_HOSTOLLAMA_CHAT_PORTOLLAMA_CHAT_LANGUAGE_MODEL
ExtractionOLLAMA_EXTRACT_HOSTOLLAMA_EXTRACT_PORTOLLAMA_EXTRACT_LANGUAGE_MODEL
Text2GremlinOLLAMA_TEXT2GQL_HOSTOLLAMA_TEXT2GQL_PORTOLLAMA_TEXT2GQL_LANGUAGE_MODEL
EmbeddingOLLAMA_EMBEDDING_HOSTOLLAMA_EMBEDDING_PORTOLLAMA_EMBEDDING_MODEL

The default host is 127.0.0.1 and the default port is 11434. Model names have no defaults; pull the required models in Ollama before use.

Reranking

SettingDefaultDescription
COHERE_BASE_URLhttps://api.cohere.com/v1/rerankCohere rerank endpoint; CO_API_URL is a fallback
RERANKER_API_KEYemptyCohere or SiliconFlow key
RERANKER_MODELemptyModel name supported by the service

HugeGraph Connection and Retrieval Limits

SettingDefaultDescription
GRAPH_URL127.0.0.1:8080HugeGraph address; it is not split into IP and port
GRAPH_NAMEhugegraphGraph name
GRAPH_USERadminUser name
GRAPH_PWDxxxPassword
GRAPH_SPACEemptyGraphSpace name
LIMIT_PROPERTYFalseWhether to limit returned properties; read as a string by the configuration class
MAX_GRAPH_PATH10Maximum graph path length
MAX_GRAPH_ITEMS30Maximum number of graph retrieval items
EDGE_LIMIT_PRE_LABEL8Result limit for each edge label
VECTOR_DIS_THRESHOLD0.9Results beyond this vector-distance threshold are ignored
TOPK_PER_KEYWORD1Candidates per keyword
TOPK_RETURN_RESULTS20Results returned after reranking

Vector Index Backend

SettingDefaultDescription
CUR_VECTOR_INDEXFaissActive vector store: Faiss, Milvus, or Qdrant
QDRANT_HOSTempty
QDRANT_PORT6333
QDRANT_API_KEYempty
MILVUS_HOSTempty
MILVUS_PORT19530
MILVUS_USERempty
MILVUS_PASSWORDempty

FAISS is local and needs no extra dependency. Selecting Milvus or Qdrant without the optional dependencies raises an error that names the missing package, so install them first:

cd hugegraph-ai
uv sync --package hugegraph-llm --extra vectordb

The same choice is available in the 5. Set up the vector engine. panel of the Web UI, which also persists the connection settings for the selected engine.

Login and Log API

SettingDefaultDescription
ENABLE_LOGINFalseWhether to require a Bearer token; read as a string by the configuration class
USER_TOKEN4321Token for the Web UI and regular APIs
ADMIN_TOKENxxxxAdministrator token used by /logs

/logs returns 403 when ADMIN_TOKEN is empty or still set to xxxx. Replace both the user and administrator tokens in production.

Minimal OpenAI Configuration

LANGUAGE=EN
CHAT_LLM_TYPE=openai
EXTRACT_LLM_TYPE=openai
TEXT2GQL_LLM_TYPE=openai
EMBEDDING_TYPE=openai

OPENAI_API_KEY=your-api-key
OPENAI_BASE_URL=https://api.openai.com/v1
OPENAI_CHAT_LANGUAGE_MODEL=gpt-4.1-mini
OPENAI_EXTRACT_LANGUAGE_MODEL=gpt-4.1-mini
OPENAI_TEXT2GQL_LANGUAGE_MODEL=gpt-4.1-mini
OPENAI_EMBEDDING_MODEL=text-embedding-3-small

GRAPH_URL=127.0.0.1:8080
GRAPH_NAME=hugegraph
GRAPH_USER=admin
GRAPH_PWD=your-password

Configuration Loading

Configuration classes supply code defaults and then apply overrides from .env and the process environment. The Web UI and configuration APIs can update current settings at runtime and write supported fields back to .env. Restart the service after editing .env manually; prompt YAML can be refreshed by the page-loading logic.

Unknown keys in .env are ignored rather than rejected, and empty values fall back to the code default. Keys are matched case-insensitively.

Configuration definitions are in:

  • hugegraph-llm/src/hugegraph_llm/config/llm_config.py
  • hugegraph-llm/src/hugegraph_llm/config/hugegraph_config.py
  • hugegraph-llm/src/hugegraph_llm/config/index_config.py
  • hugegraph-llm/src/hugegraph_llm/config/admin_config.py
  • hugegraph-llm/src/hugegraph_llm/config/prompt_config.py
  • hugegraph-llm/src/hugegraph_llm/config/models/base_config.py for the loading and file-sync behaviour

3.5 - HugeGraph-LLM REST API

The HugeGraph-LLM demo process serves both the Web UI and REST API. The default address is http://localhost:8001:

cd hugegraph-ai/hugegraph-llm
python -m hugegraph_llm.demo.rag_demo.app \
  --host 127.0.0.1 \
  --port 8001

All endpoints are POST:

PathSuccess statusPurpose
/rag200Answer a question with the selected retrieval modes
/rag/graph200Graph retrieval only, without a final answer
/graph/extract200Extract vertices and edges from text
/text2gremlin200Generate Gremlin from natural language
/config/graph201Update the HugeGraph connection
/config/llm201Update the language model
/config/embedding201Update the embedding model
/config/rerank201Update the reranker
/logs200Stream the server log

Authentication

Enable login in .env:

ENABLE_LOGIN=True
USER_TOKEN=replace-with-a-secret

Requests then require a Bearer token:

Authorization: Bearer replace-with-a-secret

The same setting puts the Gradio UI behind basic authentication, with the fixed user name rag and USER_TOKEN as the password. A wrong token returns 401 with a WWW-Authenticate: Bearer header. When ENABLE_LOGIN is left at False, every endpoint is open.

RAG

POST /rag

Returns one or more answer types according to the switches. When none is explicitly selected, only graph_only is enabled.

curl -X POST http://localhost:8001/rag \
  -H 'Content-Type: application/json' \
  -d '{
    "query": "Which movies feature Al Pacino?",
    "raw_answer": false,
    "vector_only": false,
    "graph_only": true,
    "graph_vector_answer": false,
    "max_graph_items": 30,
    "topk_return_results": 20,
    "vector_dis_threshold": 0.9,
    "topk_per_keyword": 1,
    "gremlin_tmpl_num": 1,
    "client_config": {
      "url": "127.0.0.1:8080",
      "graph": "hugegraph",
      "user": "admin",
      "pwd": "admin",
      "gs": "DEFAULT"
    }
  }'

The response contains only enabled answer fields:

{
  "query": "Which movies feature Al Pacino?",
  "graph_only": "..."
}

Other optional parameters include graph_ratio (default 0.5), rerank_method (bleu or reranker, default bleu), near_neighbor_first (default false), custom_priority_info, and the three custom prompt fields answer_prompt, keywords_extract_prompt, and gremlin_prompt. Omitting a prompt field uses the value from config_prompt.yaml.

gremlin_tmpl_num selects how Text2Gremlin runs during graph retrieval. A negative value skips Text2Gremlin and goes straight to the predefined traversal, 0 generates Gremlin without examples, and a positive value retrieves that many examples from the example index.

An empty or whitespace-only query returns 400.

POST /rag/graph

Runs graph retrieval without generating a final natural-language answer:

curl -X POST http://localhost:8001/rag/graph \
  -H 'Content-Type: application/json' \
  -d '{
    "query": "Which movies feature Al Pacino?",
    "get_vertex_only": false,
    "gremlin_tmpl_num": 1,
    "rerank_method": "bleu"
  }'

graph_recall in the response can contain query, keywords, match_vids, graph_result_flag, gremlin, graph_result, and vertex_degree_list. Set get_vertex_only=true to return immediately after vertex matching; the endpoint then replaces match_vids with the full vertex details.

An empty query returns 400, a type error in the request returns 400, and any other failure returns 500.

Graph Extraction

POST /graph/extract

An inline schema does not connect to HugeGraph:

curl -X POST http://localhost:8001/graph/extract \
  -H 'Content-Type: application/json' \
  -d '{
    "texts": ["Alice works at Acme."],
    "schema": {
      "vertexlabels": [
        {"name": "person", "properties": ["name"]},
        {"name": "company", "properties": ["name"]}
      ],
      "edgelabels": [
        {
          "name": "works_at",
          "source_label": "person",
          "target_label": "company",
          "properties": []
        }
      ]
    },
    "language": "en",
    "split_type": "sentence",
    "include_meta": true
  }'

Request fields:

FieldDefaultNotes
textsrequiredA string or an array of strings; empty or blank entries are dropped and an empty result is rejected
schemarequiredInline JSON object or string, or the name of an existing graph
example_promptprompt YAML valueExtraction prompt header
extract_typeproperty_graphOnly value currently accepted
languagezhzh or en, used for chunk splitting
split_typedocumentdocument, paragraph, or sentence
include_metafalseAdds vertex_count, edge_count, and text_count to meta
client_confignoneOnly allowed with a graph-name schema

An inline schema must be an object with vertexlabels and edgelabels lists. Every vertex label needs a non-empty name and a non-empty properties list; every edge label needs a non-empty name, source_label, and target_label. propertykeys is optional and must be a list when present.

When schema is an existing graph name, also pass client_config, and make client_config.graph match that name. client_config here accepts only graph, user, pwd, and gs; unknown fields are rejected, and there is no url field:

{
  "texts": "Alice works at Acme.",
  "schema": "hugegraph",
  "client_config": {
    "graph": "hugegraph",
    "user": "admin",
    "pwd": "admin",
    "gs": "DEFAULT"
  }
}

A successful response always contains status (always succeeded), result.vertices, result.edges, warnings, and meta. meta stays empty unless include_meta is true.

Text2Gremlin

POST /text2gremlin

curl -X POST http://localhost:8001/text2gremlin \
  -H 'Content-Type: application/json' \
  -d '{
    "query": "Find all person vertices",
    "example_num": 1,
    "output_types": ["template_gremlin", "template_execution_result"]
  }'

output_types can contain:

  • match_result
  • template_gremlin
  • raw_gremlin
  • template_execution_result
  • raw_execution_result

If omitted, only template_gremlin is returned by default. An empty array lets the implementation return all outputs. A custom gremlin_prompt must contain {query}, {schema}, {example}, and {vertices}; a missing placeholder fails request validation and names the placeholders that are absent.

example_num defaults to 0, which means no templates, and is clamped to the range 0 to 10. client_config overrides the HugeGraph connection for the request; the schema used for generation is the active graph name. An empty query returns 400, and a generation failure returns 500.

Runtime Configuration

POST /config/graph

{
  "url": "127.0.0.1:8080",
  "graph": "hugegraph",
  "user": "admin",
  "pwd": "admin",
  "gs": "DEFAULT"
}

user and pwd default to empty strings, and gs is optional.

POST /config/llm and POST /config/embedding

Both endpoints use the same request model. /config/llm sets chat_llm_type, extract_llm_type, and text2gql_llm_type to the same value; per-task types can only be set separately through .env or the Web UI. OpenAI or LiteLLM example:

{
  "llm_type": "openai",
  "api_key": "your-key",
  "api_base": "https://api.openai.com/v1",
  "language_model": "gpt-4.1-mini",
  "max_tokens": "4096"
}

Ollama requests still require the common fields; api_key and api_base can be empty strings:

{
  "llm_type": "ollama/local",
  "api_key": "",
  "api_base": "",
  "language_model": "qwen2.5:7b",
  "host": "127.0.0.1",
  "port": "11434"
}

POST /config/rerank

{
  "reranker_type": "siliconflow",
  "reranker_model": "BAAI/bge-reranker-v2-m3",
  "api_key": "your-key"
}

reranker_type accepts cohere or siliconflow. Cohere also accepts cohere_base_url.

All four configuration endpoints return 201 on success. They change the process’s active configuration and may write values back to .env. /config/llm, /config/embedding, and /config/rerank restore the previous values if applying a change raises; /config/graph does not.

client_config in /rag, /rag/graph, and /text2gremlin overrides the HugeGraph connection for one request, and only the fields actually present in the request are applied. The current implementation still changes process-global settings temporarily, so do not issue long-running requests with different connections concurrently.

Logs

POST /logs

This endpoint requires ADMIN_TOKEN in .env to be changed to a secure value. Example request body:

{
  "admin_token": "replace-with-an-admin-secret",
  "log_file": "llm-server.log"
}

log_file defaults to llm-server.log, must be a file name under logs/, and cannot be absolute, contain path separators, or resolve to . or ... Invalid names return 400.

An unset or placeholder ADMIN_TOKEN returns 403 before the token is even compared, and a wrong token returns a 403 body with the message Invalid admin_token.

The successful response is a text/plain stream that first replays the last 125 lines of the file and then follows it, in the manner of tail -f.

3.6 - Vermeer Python Client

vermeer-python-client is the Python SDK for Vermeer, the memory-first graph computing engine written in Go. The SDK wraps the REST API of the Vermeer master so you can list graphs, submit load and compute tasks, and read task state from Python. The import package is pyvermeer.

The module does not pin a Vermeer server version. It talks to the Vermeer master over HTTP using the endpoints listed in API Surface.

Requirements

  • Python 3.9 or later for the module on its own. The HugeGraph-AI repository as a whole requires Python 3.10 or later.
  • A running Vermeer master reachable over HTTP on its default port 6688. Docker deployments must publish 6688:6688; see the Vermeer quick start.
  • uv (recommended) or pip

Runtime dependencies: requests, urllib3, python-dateutil, decorator, rich, and setuptools.

Installation

The distribution name in the packaging metadata is vermeer-python-client and the version is managed independently of the repository version. The package is not published on PyPI yet, so install it from source.

From the root of the HugeGraph-AI repository, the vermeer extra installs it into the shared virtual environment:

git clone https://github.com/apache/hugegraph-ai.git
cd hugegraph-ai
uv sync --extra vermeer
source .venv/bin/activate

vermeer-python-client is wired in as an editable path dependency rather than a uv workspace member, so a plain uv sync at the repository root does not install it. You have to ask for the extra (or for --all-extras).

To install the module standalone:

git clone https://github.com/apache/hugegraph-ai.git
cd hugegraph-ai/vermeer-python-client
uv sync
source .venv/bin/activate

Connect to a Vermeer Master

from pyvermeer.client.client import PyVermeerClient

client = PyVermeerClient(
    ip="127.0.0.1",
    port=6688,
    token="",
    timeout=(0.5, 15.0),
    log_level="INFO",
)

Constructor parameters:

ParameterTypeDefaultDescription
ipstrrequiredHost name or IP address of the Vermeer master
portintrequiredREST port of the Vermeer master
tokenstrrequiredSent verbatim as the Authorization request header
timeout(float, float) or NoneNoneConnect and read timeouts in seconds
log_levelstr"INFO"Level applied to the shared VermeerClient logger

Behavior worth knowing before you connect:

  • token may be an empty string when the master does not check authorization, but it cannot be None. The session raises ValueError("Vermeer Token must be provided.") in that case.
  • timeout is a (connect, read) pair. VermeerConfig has its own default of (0.5, 15.0), but the client always forwards its own argument, so omitting timeout stores None and the request waits without a deadline. Pass the pair explicitly if you want one.
  • The base URL is always built as http://{ip}:{port}/, so the client speaks plain HTTP.
  • Every request sets Content-Type: application/json and serializes params into the request body, including for GET requests.
  • The underlying session retries up to 3 times with a backoff factor of 0.1 on HTTP 500, 502, and 504.
  • log_level sets the level of the shared logger named VermeerClient. Its console handler is fixed at INFO, so DEBUG records are not printed to the console today.

End-to-End Example

The module ships a runnable demo at vermeer-python-client/src/pyvermeer/demo/task_demo.py. The version below adds task polling with timeout and failure handling, waits for a successful load before reading the graph, and reads the HugeGraph password from the environment:

import os
import time

from pyvermeer.client.client import PyVermeerClient
from pyvermeer.structure.task_data import TaskCreateRequest

client = PyVermeerClient(
    ip="127.0.0.1",
    port=6688,
    token="",
    timeout=(0.5, 15.0),
    log_level="INFO",
)

# List the tasks the master knows about
tasks = client.tasks.get_tasks()
print(tasks.to_dict())

# Load a graph from HugeGraph into Vermeer
create_response = client.tasks.create_task(
    create_task=TaskCreateRequest(
        task_type="load",
        graph_name="DEFAULT-example",
        params={
            "load.hg_pd_peers": '["127.0.0.1:8686"]',
            "load.hugegraph_name": "DEFAULT/example/g",
            "load.hugegraph_username": "admin",
            "load.hugegraph_password": os.environ["HUGEGRAPH_PASSWORD"],
            "load.parallel": "10",
            "load.type": "hugegraph",
        },
    )
)
print(create_response.errcode, create_response.message)
if create_response.errcode != 0:
    raise RuntimeError(f"Could not create load task: {create_response.message}")

# Poll this load task until it succeeds, fails, or times out
task_id = create_response.task.id
poll_timeout = 300.0
deadline = time.monotonic() + poll_timeout
while time.monotonic() < deadline:
    task = client.tasks.get_task(task_id)
    if task.errcode != 0:
        raise RuntimeError(f"Could not read task {task_id}: {task.message}")
    state = task.task.state
    print(task_id, state)
    if state == "loaded":
        break
    if state in ("error", "canceled"):
        raise RuntimeError(f"Load task {task_id} ended with state {state}")
    remaining = deadline - time.monotonic()
    if remaining > 0:
        time.sleep(min(1.0, remaining))
else:
    raise TimeoutError(f"Load task {task_id} did not finish within {poll_timeout}s")

# Once the graph is loaded, inspect it
print(client.graph.get_graph("DEFAULT-example").to_dict())

A load task succeeds with state loaded; error or canceled stops the example without reading the graph. Adjust poll_timeout (300 seconds here) for your data size. The polling deadline is independent of HTTP connect and read timeouts, and an in-flight request and SDK retries can extend the actual wait beyond it. A timeout stops the client from waiting; it does not cancel the server-side task.

Never hardcode a real HugeGraph password into a script or a configuration file. Read it from an environment variable or a credential store, as above.

The bundled task_demo.py uses 8688. Before running it, change the PyVermeerClient port to 6688 to match the default master HTTP port. Use the command corresponding to your installation directory:

Repository-root installation (from hugegraph-ai/):

python vermeer-python-client/src/pyvermeer/demo/task_demo.py

Standalone installation (from hugegraph-ai/vermeer-python-client/):

python src/pyvermeer/demo/task_demo.py

API Surface

PyVermeerClient exposes its API groups as attributes. Two groups are registered today, graph and tasks.

client.graph

MethodVermeer endpointReturns
get_graphs()GET /graphsGraphsResponse
get_graph(graph_name)GET /graphs/{graph_name}GraphResponse

client.tasks

MethodVermeer endpointReturns
get_tasks()GET /tasksTasksResponse
get_task(task_id)GET /task/{task_id}TaskResponse
create_task(create_task)POST /tasks/createTaskCreateResponse

pyvermeer/api/master.py and pyvermeer/api/worker.py contain only the license header, and neither group is registered on the client. Master and worker information is therefore not reachable from the client yet, even though MasterResponse and WorkersResponse already exist under pyvermeer/structure/.

client.send_request(method, endpoint, params) is the shared entry point behind both groups. You can call it directly to reach a Vermeer endpoint that has no wrapper yet; it returns the decoded JSON body as a plain dict.

Requests and Responses

TaskCreateRequest(task_type, graph_name, params) is serialized as {"task_type": ..., "graph": ..., "params": ...}. Note that graph_name becomes graph on the wire, which matches the payload documented for the Vermeer REST API.

Every response type extends BaseResponse and exposes errcode and message, plus a to_dict() helper. errcode is 0 on success and 1 on error; -1 means the field was missing from the response body.

  • GraphsResponse.graphs and GraphResponse.graph yield VermeerGraph objects with name, space_name, status, create_time, update_time, vertex_count, edge_count, workers, worker_group, use_out_edges, use_property, use_out_degree, use_undirected, on_disk, and backend_option.
  • TasksResponse.tasks, TaskResponse.task, and TaskCreateResponse.task yield TaskInfo objects with id, state, create_user, create_type, create_time, start_time, update_time, graph_name, space_name, type, params, and workers.
  • Timestamps are parsed with python-dateutil into datetime objects. An empty timestamp string becomes None.

Task Parameters

The client does not validate params. Keys and values are passed straight through to Vermeer, so the accepted names come from the engine, not from the SDK. For the load parameters and the parameters of the supported algorithms, see the Vermeer quick start.

The usual sequence is the same as with the REST API directly: create a load task to read the graph into Vermeer, wait for it to finish, then create computation tasks against the loaded graph.

Errors

pyvermeer.utils.exception defines four exceptions, all raised from the underlying requests or JSON failure:

ExceptionRaised when
ConnectErrorrequests.ConnectionError, the master is unreachable
TimeOutErrorrequests.Timeout, the connect or read deadline expired
JsonDecodeErrorThe response body is not valid JSON
UnknownErrorAny other failure during the request
from pyvermeer.utils.exception import ConnectError, TimeOutError

try:
    graphs = client.graph.get_graphs()
except (ConnectError, TimeOutError) as error:
    print(error)

The client does not check the HTTP status code of the response, so inspect errcode and message on the returned object to tell success from a Vermeer-side error.

Development Checks

Run the formatting and static checks from the root of the HugeGraph-AI repository:

./style/code_format_and_analysis.sh

The source lives under vermeer-python-client/src/pyvermeer/. The module currently ships no test suite.

References

4 - HugeGraph Computing (OLAP)

The HugeGraph-Computer repository contains two OLAP systems: Vermeer, an in-memory graph computing platform implemented in Go, and Computer, a distributed BSP framework implemented in Java.

DeepWiki provides real-time updated project documentation with more comprehensive and accurate content, suitable for quickly understanding the latest project information.

📖 https://deepwiki.com/apache/hugegraph-computer/

4.1 - HugeGraph-Vermeer Quick Start

1. Overview of Vermeer

1.1 Architecture

Vermeer is a high-performance, memory-first graph computing framework written in Go (start once, execute any task), supporting ultra-fast computation of 15+ OLAP graph algorithms (most tasks complete in seconds to minutes), with master and worker roles. Currently, there is only one master (HA can be added), and there can be multiple workers.

The master is responsible for communication, forwarding, and aggregation, with minimal computation and resource usage. Workers are computation nodes used to store graph data and run computation tasks, consuming a large amount of memory and CPU. The grpc and rest modules handle internal communication and external calls, respectively.

The framework’s runtime configuration can be passed via command-line parameters or specified in configuration files located in the config/ directory. The --env parameter can specify which configuration file to use, e.g., --env=master specifies using master.ini. Note that the master needs to specify the listening port, and the worker needs to specify the listening port and the master’s ip:port.

The default master HTTP port is 6688 for REST API and Python clients. Workers connect to the master through gRPC port 6689. The Docker examples below publish HTTP with 6688:6688; keep http_peer=0.0.0.0:6688 in the master configuration.

1.2 Running Method

For both Docker options below, prepare a host configuration directory containing the provided master.ini and worker.ini files. In the existing [default] section of worker.ini, change master_peer as follows, keeping the other settings:

[default]
master_peer=vermeer-master:6689

Inside the worker container, the shipped 127.0.0.1:6689 points to the worker itself. vermeer-master resolves to the master container on the shared Docker network in both examples. Keep grpc_peer=0.0.0.0:6689 in master.ini, and mount this configuration directory at /go/bin/config in both containers. Publishing HTTP port 6688 alone does not configure the worker’s gRPC connection.

  1. Option 1: Docker Compose (Recommended)

Run the following steps from the Vermeer root directory. You can use the repository’s existing docker-compose.yaml or create one from the example below. In either case, apply the required port and volume changes below before starting the services:

services:
  vermeer-master:
    image: hugegraph/vermeer
    container_name: vermeer-master
    ports:
      - "6688:6688"
    volumes:
      - ~/.config:/go/bin/config # Change here to your actual config path
    command: --env=master
    networks:
      vermeer_network:
        ipv4_address: 172.20.0.10 # Assign a static IP for the master

  vermeer-worker:
    image: hugegraph/vermeer
    container_name: vermeer-worker
    volumes:
      - ~/.config:/go/bin/config # Change here to your actual config path
    command: --env=worker
    networks:
      vermeer_network:
        ipv4_address: 172.20.0.11 # Assign a static IP for the worker

networks:
  vermeer_network:
    driver: bridge
    ipam:
      config:
        - subnet: 172.20.0.0/24 # Define the subnet for your network

Before starting, update docker-compose.yaml whether you use the repository’s file or the example above:

  • Ports: Under services.vermeer-master, add ports: ["6688:6688"] if this mapping is missing, so host-side curl and Python clients can reach the master HTTP API.
  • Volumes: In both vermeer-master and vermeer-worker, set the bind mount for /go/bin/config to /home/user/config:/go/bin/config, replacing /home/user/config with the absolute configuration directory prepared above. Replace the existing mount regardless of whether it uses ~/ (the repository’s file) or ~/.config (the example above).
  • Subnet: Modify the subnet IP based on your actual situation. Note that the ports each container needs to access are specified in the config file. Please refer to the contents of the project’s config folder for details.

Build the Image and Start in the Project Directory (or docker build first, then docker-compose up)

# Build the image (in the project root vermeer directory)
docker build -t hugegraph/vermeer .

# Start the services (in the vermeer root directory)
docker-compose up -d
# Or use the new CLI:
# docker compose up -d

View Logs / Stop / Remove

docker-compose logs -f
docker-compose down
  1. Option 2: Start individually via docker run (Manually create network and assign static IP)

Set CONFIG_DIR to the configuration directory prepared above, with master_peer=vermeer-master:6689 in worker.ini. Ensure it has proper read/execute permissions for the Docker process.

Build the image:

docker build -t hugegraph/vermeer .

Create a custom bridge network (one-time operation):

docker network create --driver bridge \
  --subnet 172.20.0.0/24 \
  vermeer_network

Run master (adjust CONFIG_DIR to your absolute configuration path, and you can adjust the IP as needed based on your actual situation).

CONFIG_DIR=/home/user/config

docker run -d \
  --name vermeer-master \
  --network vermeer_network --ip 172.20.0.10 \
  -p 6688:6688 \
  -v ${CONFIG_DIR}:/go/bin/config \
  hugegraph/vermeer \
  --env=master

Run worker:

docker run -d \
  --name vermeer-worker \
  --network vermeer_network --ip 172.20.0.11 \
  -v ${CONFIG_DIR}:/go/bin/config \
  hugegraph/vermeer \
  --env=worker

View logs / Stop / Remove:

docker logs -f vermeer-master
docker logs -f vermeer-worker

docker stop vermeer-master vermeer-worker
docker rm vermeer-master vermeer-worker

# Remove the custom network (if needed)
docker network rm vermeer_network
  1. Option 3: Build from Source

Build. You can refer Vermeer Readme.

go build

Enter the directory and input ./vermeer --env=master or ./vermeer --env=worker01.

After starting the master, check its HTTP port from the host:

curl --fail --show-error http://localhost:6688/graphs

The request should return HTTP 200 with errcode set to 0 in the JSON response.

2. Task Creation REST API

2.1 Introduction

This REST API provides all task creation functions, including reading graph data and various computation functions, offering both asynchronous and synchronous return interfaces. The returned content includes information about the created tasks. The overall process of using Vermeer is to first create a task to read the graph data, and after the graph is read, create a computation task to execute the computation. The graph will not be automatically deleted; multiple computation tasks can be run on one graph without repeated reading. If deletion is needed, the delete graph interface can be used. Task statuses can be divided into graph reading task status and computation task status. Generally, the client only needs to know four statuses: created, in progress, completed, and error. The graph status is the basis for determining whether the graph is available. If the graph is being read or the graph status is erroneous, the graph cannot be used to create computation tasks. The delete graph interface is only available when the graph is in the loaded or error status and has no computation tasks.

Available URLs are as follows:

  • Asynchronous return interface: POST http://master_ip:port/tasks/create returns only whether the task creation is successful, and the task status needs to be actively queried to determine completion.
  • Synchronous return interface: POST http://master_ip:port/tasks/create/sync returns after the task is completed.

2.2 Loading Graph Data

Refer to the Vermeer parameter list document for specific parameters.

Vermeer provides three ways to load data:

  1. Load from Local Files

You can obtain the dataset in advance, such as the Twitter-2010 dataset. Acquisition method: https://snap.stanford.edu/data/twitter-2010.html The first Twitter-2010.text.gz is sufficient.

Request Example:

POST http://localhost:6688/tasks/create
{
 "task_type": "load",
 "graph": "testdb",
 "params": {
  "load.parallel": "50",
  "load.type": "local",
  "load.vertex_files": "{\"localhost\":\"data/twitter-2010.v_[0,99]\"}",
  "load.edge_files": "{\"localhost\":\"data/twitter-2010.e_[0,99]\"}",
  "load.use_out_degree": "1",
  "load.use_outedge": "1"
 }
}
  1. Load from HugeGraph

Request Example:

⚠️ Security Warning: Never store real passwords in configuration files or code. Use environment variables or a secure credential management system instead.

POST http://localhost:6688/tasks/create
{
  "task_type": "load",
  "graph": "testdb",
  "params": {
    "load.parallel": "50",
    "load.type": "hugegraph",
    "load.hg_pd_peers": "[\"<your-hugegraph-ip>:8686\"]",
    "load.hugegraph_name": "DEFAULT/hugegraph2/g",
    "load.hugegraph_username": "admin",
    "load.hugegraph_password": "<your-password-here>",
    "load.use_out_degree": "1",
    "load.use_outedge": "1"
  }
}
  1. Load from HDFS

Request Example:

POST http://localhost:6688/tasks/create
{
  "task_type": "load",
  "graph": "testdb",
  "params": {
    "load.parallel": "50",
    "load.type": "hdfs",
    "load.hdfs_namenode": "name_node1:9000",
    "load.hdfs_conf_path": "/path/to/conf",
    "load.krb_realm": "EXAMPLE.COM",
    "load.krb_name": "user@EXAMPLE.COM",
    "load.krb_keytab_path": "/path/to/keytab",
    "load.krb_conf_path": "/path/to/krb5.conf",
    "load.hdfs_use_krb": "1",
    "load.vertex_files": "/data/graph/vertices",
    "load.edge_files": "/data/graph/edges",
    "load.use_out_degree": "1",
    "load.use_outedge": "1"
  }
}

2.3 Output Computation Results

All Vermeer computation tasks support multiple result output methods, which can be customized: local, hdfs, afs, or hugegraph. Add the corresponding parameters under the params parameter when sending the request to take effect. When output.need_statistics is set to 1, it supports outputting statistical information of the computation results, which will be written in the interface task information. The statistical mode operators currently support “count” and “modularity,” but only for community detection algorithms.

Refer to the Vermeer parameter list document for specific parameters.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "pagerank",
 "compute.parallel": "10",
 "compute.max_step": "10",
 "output.type": "local",
 "output.parallel": "1",
 "output.file_path": "result/pagerank"
  }
}

3. Supported Algorithms

3.1 PageRank

The PageRank algorithm, also known as the web ranking algorithm, is a technique used by search engines to calculate the relevance and importance of web pages (nodes) based on their mutual hyperlinks.

  • If a web page is linked to by many other web pages, it indicates that the web page is relatively important, and its PageRank value will be relatively high.
  • If a web page with a high PageRank value links to other web pages, the PageRank value of the linked web pages will also increase accordingly.

The PageRank algorithm is suitable for scenarios such as web page ranking and identifying key figures in social networks.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "pagerank",
 "compute.parallel":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/pagerank",
 "compute.max_step":"10"
 }
}

3.2 WCC (Weakly Connected Components)

The weakly connected components algorithm calculates all connected subgraphs in an undirected graph and outputs the weakly connected subgraph ID to which each vertex belongs, indicating the connectivity between points and distinguishing different connected communities.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "wcc",
 "compute.parallel":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/wcc",
 "compute.max_step":"10"
 }
}

3.3 LPA (Label Propagation Algorithm)

The label propagation algorithm is a graph clustering algorithm commonly used in social networks to discover potential communities.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "lpa",
 "compute.parallel":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/lpa",
 "compute.max_step":"10"
 }
}

3.4 Degree Centrality

The degree centrality algorithm calculates the degree centrality value of each node in the graph, supporting both undirected and directed graphs. Degree centrality is an important indicator of node importance; the more edges a node has with other nodes, the higher its degree centrality value, and the more important the node is in the graph. In an undirected graph, degree centrality is calculated based on edge information to count the number of times a node appears, resulting in the degree centrality value of the node. In a directed graph, it is based on the direction of the edges, filtering based on input or output-edge information to count the number of times a node appears, resulting in the in-degree or out-degree value of the node. It indicates the importance of each point, with more important points having higher degrees.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "degree",
 "compute.parallel":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/degree",
 "degree.direction":"both"
 }
}

3.5 Closeness Centrality

Closeness centrality is used to calculate the inverse of the shortest distance from a node to all other reachable nodes, accumulating and normalizing the value. Closeness centrality can be used to measure the time it takes for information to be transmitted from the node to other nodes. The larger the closeness centrality of a node, the closer its position in the graph is to the center, suitable for scenarios such as identifying key nodes in social networks.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "closeness_centrality",
 "compute.parallel":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/closeness_centrality",
 "closeness_centrality.sample_rate":"0.01"
 }
}

3.6 Betweenness Centrality

The betweenness centrality algorithm determines the value of a node as a “bridge” node; the larger the value, the more likely it is to be a necessary path between two points in the graph. Typical examples include mutual followers in social networks. It is suitable for measuring the degree of aggregation around a node in a community.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "betweenness_centrality",
 "compute.parallel":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/betweenness_centrality",
 "betweenness_centrality.sample_rate":"0.01"
 }
}

3.7 Triangle Count

The triangle count algorithm calculates the number of triangles passing through each vertex, suitable for calculating the relationships between users and whether the associations form triangles. The more triangles, the higher the degree of association between nodes in the graph, and the tighter the organizational relationship. In social networks, triangles indicate cohesive communities, and identifying triangles helps understand clustering and interconnections among individuals or groups in the network. In financial or transaction networks, the presence of triangles may indicate suspicious or fraudulent activities, and triangle counting can help identify transaction patterns that may require further investigation.

The output result is the Triangle Count corresponding to each vertex, i.e., the number of triangles the vertex is part of.

Note: This algorithm is for undirected graphs and ignores edge directions.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "triangle_count",
 "compute.parallel":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/triangle_count"
 }
}

3.8 K-Core

The K-Core algorithm marks all vertices with a degree of K, suitable for graph pruning and finding the core part of the graph.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "kcore",
 "compute.parallel":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/kcore",
 "kcore.degree_k":"5"
 }
}

3.9 SSSP (Single Source Shortest Path)

The single source the shortest path algorithm calculates the shortest distance from one point to all other points.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "sssp",
 "compute.parallel":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/degree",
 "sssp.source":"tom"
 }
}

3.10 KOUT

Starting from a point, get the k-layer nodes of this point.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "kout",
 "compute.parallel":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/kout",
 "kout.source":"tom",
 "compute.max_step":"6"
 }
}

3.11 Louvain

The Louvain algorithm is a community detection algorithm based on modularity. The basic idea is that nodes in the network try to traverse all neighbor community labels and choose the community label that maximizes the modularity increment. After maximizing modularity, each community is regarded as a new node, and the process is repeated until the modularity no longer increases.

The distributed Louvain algorithm implemented on Vermeer is affected by factors such as node order and parallel computation. Due to the random traversal order of the Louvain algorithm, community compression also has a certain randomness, leading to different results in multiple executions. However, the overall trend will not change significantly.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "louvain",
 "compute.parallel":"10",
 "compute.max_step":"1000",
 "louvain.threshold":"0.0000001",
 "louvain.resolution":"1.0",
 "louvain.step":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/louvain"
  }
 }

3.12 Jaccard Similarity Coefficient

The Jaccard index, also known as the Jaccard similarity coefficient, is used to compare the similarity and diversity between finite sample sets. The larger the Jaccard coefficient value, the higher the similarity of the samples. It is used to calculate the Jaccard similarity coefficient between a given source point and all other points in the graph.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "jaccard",
 "compute.parallel":"10",
 "compute.max_step":"2",
 "jaccard.source":"123",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/jaccard"
 }
}

3.13 Personalized PageRank

The goal of personalized PageRank is to calculate the relevance of all nodes relative to user u. Starting from the node corresponding to user u, at each node, there is a probability of 1-d to stop walking and start again from u, or a probability of d to continue walking, randomly selecting a node from the nodes pointed to by the current node to walk down. It is used to calculate the personalized PageRank score starting from a given starting point, suitable for scenarios such as social recommendations.

Since the calculation requires using out-degree, load.use_out_degree needs to be set to 1 when reading the graph.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "ppr",
 "compute.parallel":"100",
 "compute.max_step":"10",
 "ppr.source":"123",
 "ppr.damping":"0.85",
 "ppr.diff_threshold":"0.00001",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/ppr"
 }
}

3.14 Global Kout

Calculate the k-degree neighbors of all nodes in the graph (excluding themselves and 1~k-1 degree neighbors). Due to the severe memory expansion of the global kout algorithm, k is currently limited to 1 and 2. Additionally, the global kout algorithm supports filtering functions (parameters such as “compute.filter”:“risk_level==1”), and the filtering condition is judged when calculating the k-degree. The final result set includes those that meet the filtering condition. The algorithm’s final output is the number of neighbors that meet the condition.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "kout_all",
 "compute.parallel":"10",
 "output.type":"local",
 "output.parallel":"10",
 "output.file_path":"result/kout",
 "compute.max_step":"2",
 "compute.filter":"risk_level==1"
 }
}

3.15 Clustering Coefficient

The clustering coefficient represents the coefficient of the clustering degree of nodes in a graph. In real networks, especially in specific networks, nodes tend to establish a tightly organized relationship due to relatively high-density connection points. The clustering coefficient algorithm (Cluster Coefficient) is used to calculate the clustering degree of nodes in the graph. This algorithm is for local clustering coefficients. The local clustering coefficient can measure the clustering degree around each node in the graph.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "clustering_coefficient",
 "compute.parallel":"100",
 "compute.max_step":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/cc"
 }
}

3.16 SCC (Strongly Connected Components)

In the mathematical theory of directed graphs, if every vertex of a graph can be reached from any other point in the graph, the graph is said to be strongly connected. The parts of any directed graph that can achieve strong connectivity are called strongly connected components. It indicates the connectivity between points and distinguishes different connected communities.

Request example:

POST http://localhost:6688/tasks/create
{
 "task_type": "compute",
 "graph": "testdb",
 "params": {
 "compute.algorithm": "scc",
 "compute.parallel":"10",
 "output.type":"local",
 "output.parallel":"1",
 "output.file_path":"result/scc",
 "compute.max_step":"200"
 }
}

🚧, further updates and improvements will be made at any time. Suggestions and feedback are welcome.

4.2 - HugeGraph-Computer Quick Start

1 HugeGraph-Computer Overview

The HugeGraph-Computer is a distributed graph processing system for HugeGraph (OLAP). It is an implementation of Pregel. It runs on a Kubernetes(K8s) framework.(It focuses on supporting graph data volumes of hundreds of billions to trillions, using disk for sorting and acceleration, which is one of the biggest differences from Vermeer)

Features

  • Support distributed MPP graph computing, and integrates with HugeGraph as graph input/output storage.
  • Based on the BSP (Bulk Synchronous Parallel) model, an algorithm performs computing through multiple parallel iterations; every iteration is a superstep.
  • Auto memory management. The framework will never be OOM(Out of Memory) since it will split some data to disk if it doesn’t have enough memory to hold all the data.
  • The part of edges or the messages of super node can be in memory, so you will never lose it.
  • You can load the data from HDFS or HugeGraph, or any other system.
  • You can output the results to HDFS or HugeGraph, or any other system.
  • Easy to develop a new algorithm. You just need to focus on vertex-only processing just like as in a single server, without worrying about message transfer and memory/storage management.

2 Dependency for Building/Running

2.1 Install Java 11 (JDK 11)

Must use ≥ Java 11 to run Computer, and configure by yourself.

Be sure to execute the java -version command to check the jdk version before reading

3 Get Started

3.1 Run PageRank algorithm locally

To run the algorithm with HugeGraph-Computer, you need to install Java 11 or later versions.

You also need to deploy HugeGraph-Server and Etcd.

There are two ways to get HugeGraph-Computer:

  • Download the compiled tarball
  • Clone source code then compile and package

3.1.1 Download the compiled archive

Download the latest version of the HugeGraph-Computer release package:

wget https://downloads.apache.org/hugegraph/${version}/apache-hugegraph-computer-incubating-${version}.tar.gz
tar zxvf apache-hugegraph-computer-incubating-${version}.tar.gz -C hugegraph-computer

3.1.2 Clone source code to compile and package

Clone the latest version of HugeGraph-Computer source package:

$ git clone https://github.com/apache/hugegraph-computer.git

Compile and generate tar package:

cd hugegraph-computer
mvn clean package -DskipTests

3.1.3 Configure computer.properties

Edit conf/computer.properties to configure the connection to HugeGraph-Server and etcd:

# Job configuration
job.id=local_pagerank_001
job.partitions_count=4

# HugeGraph connection (✅ Correct configuration keys)
hugegraph.url=http://localhost:8080
hugegraph.name=hugegraph
# If authentication is enabled on HugeGraph-Server
hugegraph.username=
hugegraph.password=

# BSP coordination (✅ Correct key: bsp.etcd_endpoints)
bsp.etcd_endpoints=http://localhost:2379
bsp.max_super_step=10

# Algorithm parameters (⚠️ Required)
algorithm.params_class=org.apache.hugegraph.computer.algorithm.centrality.pagerank.PageRankParams

Important Configuration Notes:

  • Use bsp.etcd_endpoints (NOT bsp.etcd.url) for etcd connection
  • algorithm.params_class is required for all algorithms
  • For multiple etcd endpoints, use comma-separated list: http://host1:2379,http://host2:2379

3.1.4 Start master node

You can use the -c parameter to specify the configuration file. For more computer configuration options, see Computer Config Options

cd hugegraph-computer
bin/start-computer.sh -d local -r master

3.1.5 Start worker node

bin/start-computer.sh -d local -r worker

3.1.6 Query algorithm results

3.1.6.1 Enable OLAP index query for server

If the OLAP index is not enabled, it needs to be enabled. More reference: modify-graphs-read-mode

PUT http://localhost:8080/graphspaces/DEFAULT/graphs/hugegraph/graph_read_mode

"ALL"

3.1.6.2 Query page_rank property value:

curl "http://localhost:8080/graphspaces/DEFAULT/graphs/hugegraph/graph/vertices?page&limit=3" | gunzip

3.2 Run PageRank algorithm in Kubernetes

To run an algorithm with HugeGraph-Computer, you need to deploy HugeGraph-Server first

3.2.1 Install HugeGraph-Computer CRD

# Kubernetes version >= v1.16
kubectl apply -f https://raw.githubusercontent.com/apache/hugegraph-computer/master/computer-k8s-operator/manifest/hugegraph-computer-crd.v1.yaml

# Kubernetes version < v1.16
kubectl apply -f https://raw.githubusercontent.com/apache/hugegraph-computer/master/computer-k8s-operator/manifest/hugegraph-computer-crd.v1beta1.yaml

3.2.2 Show CRD

kubectl get crd

NAME                                        CREATED AT
hugegraphcomputerjobs.hugegraph.apache.org   2021-09-16T08:01:08Z

3.2.3 Install hugegraph-computer-operator&etcd-server

kubectl apply -f https://raw.githubusercontent.com/apache/hugegraph-computer/master/computer-k8s-operator/manifest/hugegraph-computer-operator.yaml

3.2.4 Wait for hugegraph-computer-operator&etcd-server deployment to complete

kubectl get pod -n hugegraph-computer-operator-system

NAME                                                              READY   STATUS    RESTARTS   AGE
hugegraph-computer-operator-controller-manager-58c5545949-jqvzl   1/1     Running   0          15h
hugegraph-computer-operator-etcd-28lm67jxk5                       1/1     Running   0          15h

3.2.5 Submit a job

For more information about the computer CRD, see Computer CRD

For more computer configuration options, see Computer Config Options

Basic Example:

cat <<EOF | kubectl apply --filename -
apiVersion: hugegraph.apache.org/v1
kind: HugeGraphComputerJob
metadata:
  namespace: hugegraph-computer-operator-system
  name: &jobName pagerank-sample
spec:
  jobId: *jobName
  algorithmName: page_rank  # ✅ Correct: use underscore format (matches algorithm implementation)
  image: hugegraph/hugegraph-computer:latest
  jarFile: /hugegraph/hugegraph-computer/algorithm/builtin-algorithm.jar
  pullPolicy: Always
  workerCpu: "4"
  workerMemory: "4Gi"
  workerInstances: 5
  computerConf:
    job.partitions_count: "20"
    algorithm.params_class: org.apache.hugegraph.computer.algorithm.centrality.pagerank.PageRankParams
    hugegraph.url: http://${hugegraph-server-host}:${hugegraph-server-port}
    hugegraph.name: hugegraph
EOF

Complete Example with Advanced Features:

cat <<EOF | kubectl apply --filename -
apiVersion: hugegraph.apache.org/v1
kind: HugeGraphComputerJob
metadata:
  namespace: hugegraph-computer-operator-system
  name: &jobName pagerank-advanced
spec:
  jobId: *jobName
  algorithmName: page_rank  # ✅ Correct: underscore format
  image: hugegraph/hugegraph-computer:latest
  jarFile: /hugegraph/hugegraph-computer/algorithm/builtin-algorithm.jar
  pullPolicy: Always

  # Resource limits
  masterCpu: "2"
  masterMemory: "2Gi"
  workerCpu: "4"
  workerMemory: "4Gi"
  workerInstances: 5

  # JVM options
  jvmOptions: "-Xmx3g -Xms3g -XX:+UseG1GC"

  # Environment variables (optional)
  envVars:
    - name: REMOTE_JAR_URI
      value: "http://example.com/custom-algorithm.jar"  # Download custom algorithm JAR
    - name: LOG_LEVEL
      value: "INFO"

  # Computer configuration
  computerConf:
    # Job settings
    job.partitions_count: "20"

    # Algorithm parameters (⚠️ Required)
    algorithm.params_class: org.apache.hugegraph.computer.algorithm.centrality.pagerank.PageRankParams
    page_rank.alpha: "0.85"  # PageRank damping factor

    # HugeGraph connection
    hugegraph.url: http://hugegraph-server:8080
    hugegraph.name: hugegraph
    hugegraph.username: ""  # Fill if authentication is enabled
    hugegraph.password: ""

    # BSP configuration (⚠️ System-managed in K8s, do not override)
    # bsp.etcd_endpoints is automatically set by operator
    bsp.max_super_step: "20"
    bsp.log_interval: "30000"

    # Snapshot configuration (optional)
    snapshot.write: "true"       # Enable snapshot writing
    snapshot.load: "false"       # Do not load from snapshot this time
    snapshot.name: "pagerank-snapshot-v1"
    snapshot.minio_endpoint: "http://minio:9000"
    snapshot.minio_access_key: "minioadmin"
    snapshot.minio_secret_key: "minioadmin"
    snapshot.minio_bucket_name: "hugegraph-snapshots"

    # Output configuration
    output.result_name: "page_rank"
    output.batch_size: "500"
    output.with_adjacent_edges: "false"
EOF

Configuration Notes:

Configuration Key⚠️ Important Notes
algorithmNameMust use page_rank (underscore format), matches the algorithm’s name() method return value
bsp.etcd_endpointsSystem-managed in K8s - automatically set by operator, do not override in computerConf
algorithm.params_classRequired - must specify for all algorithms
REMOTE_JAR_URIOptional environment variable to download custom algorithm JAR from remote URL
snapshot.*Optional - enable snapshots for checkpoint recovery or repeated computations

3.2.6 Show job

kubectl get hcjob/pagerank-sample -n hugegraph-computer-operator-system

NAME               JOBID              JOBSTATUS
pagerank-sample    pagerank-sample    RUNNING

3.2.7 Show log of nodes

# Show the master log
kubectl logs -l component=pagerank-sample-master -n hugegraph-computer-operator-system

# Show the worker log
kubectl logs -l component=pagerank-sample-worker -n hugegraph-computer-operator-system

# Show diagnostic log of a job
# NOTE: diagnostic log exist only when the job fails, and it will only be saved for one hour.
kubectl get event --field-selector reason=ComputerJobFailed --field-selector involvedObject.name=pagerank-sample -n hugegraph-computer-operator-system

3.2.8 Show success event of a job

NOTE: it will only be saved for one hour

kubectl get event --field-selector reason=ComputerJobSucceed --field-selector involvedObject.name=pagerank-sample -n hugegraph-computer-operator-system

3.2.9 Query algorithm results

If the output to Hugegraph-Server is consistent with Locally, if output to HDFS, please check the result file in the directory of /hugegraph-computer/results/{jobId} directory.


3.3 Local Mode vs Kubernetes Mode

Understanding the differences helps you choose the right deployment mode for your use case.

FeatureLocal ModeKubernetes Mode
Configurationconf/computer.properties fileCRD YAML computerConf field
Etcd ManagementManual deployment of external etcdOperator auto-deploys etcd StatefulSet
Worker ScalingManual start of multiple processesCRD workerInstances field auto-scales
Resource IsolationShared host resourcesPod-level CPU/Memory limits
Remote JARJAR_FILE_PATH environment variableCRD remoteJarUri or envVars.REMOTE_JAR_URI
Log ViewingLocal logs/ directorykubectl logs command
Fault RecoveryManual process restartK8s auto-restarts failed pods
Use CasesDevelopment, testing, small datasetsProduction, large-scale data

Local Mode Prerequisites:

  • Java 11+
  • HugeGraph-Server running on localhost:8080
  • Etcd running on localhost:2379

K8s Mode Prerequisites:

  • Kubernetes cluster (version 1.16+)
  • HugeGraph-Server accessible from cluster
  • HugeGraph-Computer Operator installed

Configuration Key Differences:

# Local Mode (computer.properties)
bsp.etcd_endpoints=http://localhost:2379  # ✅ User-configured
job.workers_count=4                        # User-configured
# K8s Mode (CRD)
spec:
  workerInstances: 5  # Overrides job.workers_count
  computerConf:
    # bsp.etcd_endpoints is auto-set by operator, do NOT configure
    job.partitions_count: "20"

3.4 Common Troubleshooting

3.4.1 Configuration Errors

Error: “Failed to connect to etcd”

Symptoms: Master or Worker cannot connect to etcd

Local Mode Solutions:

# Check configuration key name (common mistake)
grep "bsp.etcd_endpoints" conf/computer.properties
# Should output: bsp.etcd_endpoints=http://localhost:2379

# ❌ WRONG: bsp.etcd.url (old/incorrect key)
# ✅ CORRECT: bsp.etcd_endpoints

# Test etcd connectivity
curl http://localhost:2379/version

K8s Mode Solutions:

# Check Operator etcd service
kubectl get svc hugegraph-computer-operator-etcd -n hugegraph-computer-operator-system

# Verify etcd pod is running
kubectl get pods -n hugegraph-computer-operator-system -l app=hugegraph-computer-operator-etcd
# Should show: Running status

# Test connectivity from worker pod
kubectl exec -it pagerank-sample-worker-0 -n hugegraph-computer-operator-system -- \
  curl http://hugegraph-computer-operator-etcd:2379/version

Error: “Algorithm class not found”

Symptoms: Cannot find algorithm implementation class

Cause: Incorrect algorithmName format

# ❌ WRONG formats:
algorithmName: pageRank   # Camel case
algorithmName: PageRank   # Title case

# ✅ CORRECT format (matches PageRank.name() return value):
algorithmName: page_rank  # Underscore lowercase

Verification:

# Check algorithm implementation in source code
# File: computer-algorithm/.../PageRank.java
# Method: public String name() { return "page_rank"; }

Error: “Required option ‘algorithm.params_class’ is missing”

Solution:

computerConf:
  algorithm.params_class: org.apache.hugegraph.computer.algorithm.centrality.pagerank.PageRankParams  # ⚠️ Required

3.4.2 K8s Deployment Issues

Issue: REMOTE_JAR_URI not working

Solution:

spec:
  envVars:
    - name: REMOTE_JAR_URI
      value: "http://example.com/my-algorithm.jar"

Issue: Etcd connection timeout in K8s

Check Operator etcd:

# Verify etcd is running
kubectl get pods -n hugegraph-computer-operator-system -l app=hugegraph-computer-operator-etcd
# Should show: Running

# From worker pod, test etcd connectivity
kubectl exec -it pagerank-sample-worker-0 -n hugegraph-computer-operator-system -- \
  curl http://hugegraph-computer-operator-etcd:2379/version

Issue: Snapshot/MinIO configuration problems

Verify MinIO service:

# Test MinIO reachability
kubectl run -it --rm debug --image=alpine --restart=Never -- sh
wget -O- http://minio:9000/minio/health/live

# Test bucket permissions (requires MinIO client)
mc config host add myminio http://minio:9000 minioadmin minioadmin
mc ls myminio/hugegraph-snapshots

3.4.3 Job Status Checks

Check job overall status:

kubectl get hcjob pagerank-sample -n hugegraph-computer-operator-system
# Output example:
# NAME              JOBSTATUS   SUPERSTEP   MAXSUPERSTEP   SUPERSTEPSTAT
# pagerank-sample   Running     5           20             COMPUTING

Check detailed events:

kubectl describe hcjob pagerank-sample -n hugegraph-computer-operator-system

Check failure reasons:

kubectl get events --field-selector reason=ComputerJobFailed \
  --field-selector involvedObject.name=pagerank-sample \
  -n hugegraph-computer-operator-system

Real-time master logs:

kubectl logs -f -l component=pagerank-sample-master -n hugegraph-computer-operator-system

All worker logs:

kubectl logs -l component=pagerank-sample-worker -n hugegraph-computer-operator-system --all-containers=true

4. Built-In algorithms document

4.1 Supported algorithms list:

Centrality Algorithm:
  • PageRank
  • BetweennessCentrality
  • ClosenessCentrality
  • DegreeCentrality
Community Algorithm:
  • ClusteringCoefficient
  • Kcore
  • Lpa
  • TriangleCount
  • Wcc
Path Algorithm:
  • RingsDetection
  • RingsDetectionWithFilter

More algorithms please see: Built-In algorithms

4.2 Algorithm describe

TODO

5 Algorithm development guide

TODO

6 Note

  • If some classes under computer-k8s cannot be found, you need to execute mvn compile in advance to generate corresponding classes.

4.3 - HugeGraph-Computer Configuration Reference

Computer Config Options

The defaults in the tables come from ComputerOptions.java in the computer-api module. When the distribution’s conf/computer.properties explicitly overrides an option, the table shows “code default (packaged: actual value)”. At runtime, values in the configuration file take precedence.


1. Basic Configuration

Core job settings for HugeGraph-Computer.

config optiondefault valuedescription
hugegraph.urlhttp://127.0.0.1:8080The HugeGraph server URL to load data and write results back.
hugegraph.namehugegraphThe graph name to load data and write results back.
hugegraph.username"" (empty)The username for HugeGraph authentication (leave empty if authentication is disabled).
hugegraph.password"" (empty)The password for HugeGraph authentication (leave empty if authentication is disabled).
job.idlocal_0001 (packaged: local_001)The job identifier on YARN cluster or K8s cluster.
job.namespace"" (empty)The job namespace used to separate different data sources. This option is managed by the runtime system.
job.workers_count1The number of workers for one graph algorithm job. In K8s, this option is set by the Operator.
job.partitions_count1The number of partitions for computing one graph algorithm job.
job.partitions_thread_nums4The number of threads for partition parallel compute.

2. Algorithm Configuration

Algorithm-specific configuration for computation logic.

config optiondefault valuedescription
algorithm.params_classComputerOptions.Null placeholder classRequired. The class used to pass algorithm parameters before the algorithm runs.
algorithm.result_classComputerOptions.Null placeholder classThe vertex value class used to store computation results.
algorithm.message_classComputerOptions.Null placeholder classThe message class passed while computing a vertex.

3. Input Configuration

Configuration for loading input data from HugeGraph or other sources.

3.1 Input Source

config optiondefault valuedescription
input.source_typehugegraph-serverThe source type to load input data, allowed values: [‘hugegraph-server’, ‘hugegraph-loader’]. The ‘hugegraph-loader’ means use hugegraph-loader to load data from HDFS or file. If using ‘hugegraph-loader’, please configure ‘input.loader_struct_path’ and ‘input.loader_schema_path’.
input.loader_struct_path"" (empty)The structure path for Loader input. It takes effect only when input.source_type=hugegraph-loader.
input.loader_schema_path"" (empty)The schema path for Loader input. It takes effect only when input.source_type=hugegraph-loader.

3.2 Input Splits

config optiondefault valuedescription
input.split_size1048576 (1 MB)The input split size in bytes.
input.split_max_splits10000000The maximum number of input splits.
input.split_page_size500The page size for streamed load input split data.
input.split_fetch_timeout300The timeout in seconds to fetch input splits.

3.3 Input Processing

config optiondefault valuedescription
input.filter_classorg.apache.hugegraph.computer.core.input.filter.DefaultInputFilterThe class to create input-filter object. Input-filter is used to filter vertex edges according to user needs.
input.edge_directionOUTThe direction of edges to load, allowed values: [OUT, IN, BOTH]. When the value is BOTH, edges in both OUT and IN directions will be loaded.
input.edge_freqMULTIPLEThe frequency of edges that can exist between a pair of vertices, allowed values: [SINGLE, SINGLE_PER_LABEL, MULTIPLE]. SINGLE means only one edge can exist between a pair of vertices (identified by sourceId + targetId); SINGLE_PER_LABEL means each edge label can have one edge between a pair of vertices (identified by sourceId + edgeLabel + targetId); MULTIPLE means many edges can exist between a pair of vertices (identified by sourceId + edgeLabel + sortValues + targetId).
input.max_edges_in_one_vertex200The maximum number of adjacent edges allowed to be attached to a vertex. The adjacent edges will be stored and transferred together as a batch unit.

3.4 Input Performance

config optiondefault valuedescription
input.send_thread_nums4The number of threads for parallel sending of vertices or edges.

4. Snapshot & Storage Configuration

HugeGraph-Computer supports snapshot functionality to save vertex/edge partitions to local storage or MinIO object storage, enabling checkpoint recovery or accelerating repeated computations.

4.1 Basic Snapshot Configuration

config optiondefault valuedescription
snapshot.writefalseWhether to write snapshots of input vertex/edge partitions.
snapshot.loadfalseWhether to load from snapshots of vertex/edge partitions.
snapshot.name"" (empty)User-defined snapshot name to distinguish different snapshots.

4.2 MinIO Integration (Optional)

MinIO can be used as a distributed object storage backend for snapshots in K8s deployments.

config optiondefault valuedescription
snapshot.minio_endpoint"" (empty)MinIO service endpoint (e.g., http://minio:9000). Required when using MinIO.
snapshot.minio_access_keyminioadminMinIO access key for authentication.
snapshot.minio_secret_keyminioadminMinIO secret key for authentication.
snapshot.minio_bucket_name"" (empty)MinIO bucket name for storing snapshot data.

Usage Scenarios:

  • Checkpoint Recovery: Resume from snapshots after job failures, avoiding data reloading
  • Repeated Computations: Load data from snapshots when running the same algorithm multiple times
  • A/B Testing: Save multiple snapshot versions of the same dataset to test different algorithm parameters

Example: Local Snapshot (in computer.properties):

snapshot.write=true
snapshot.name=pagerank-snapshot-20260201

Example: MinIO Snapshot (in K8s CRD computerConf):

computerConf:
  snapshot.write: "true"
  snapshot.name: "pagerank-snapshot-v1"
  snapshot.minio_endpoint: "http://minio:9000"
  snapshot.minio_access_key: "my-access-key"
  snapshot.minio_secret_key: "my-secret-key"
  snapshot.minio_bucket_name: "hugegraph-snapshots"

5. Worker & Master Configuration

Configuration for worker and master computation logic.

5.1 Master Configuration

config optiondefault valuedescription
master.computation_classorg.apache.hugegraph.computer.core.master.DefaultMasterComputationMaster-computation is computation that can determine whether to continue to the next superstep. It runs at the end of each superstep on the master.

5.2 Worker Computation

config optiondefault valuedescription
worker.computation_classorg.apache.hugegraph.computer.core.config.NullThe class to create worker-computation object. Worker-computation is used to compute each vertex in each superstep.
worker.combiner_classorg.apache.hugegraph.computer.core.config.NullCombiner can combine messages into one value for a vertex. For example, PageRank algorithm can combine messages of a vertex to a sum value.
worker.partitionerorg.apache.hugegraph.computer.core.graph.partition.HashPartitionerThe partitioner that decides which partition a vertex should be in, and which worker a partition should be in.

5.3 Worker Combiners

config optiondefault valuedescription
worker.vertex_properties_combiner_classorg.apache.hugegraph.computer.core.combiner.OverwritePropertiesCombinerThe combiner can combine several properties of the same vertex into one properties at input step.
worker.edge_properties_combiner_classorg.apache.hugegraph.computer.core.combiner.OverwritePropertiesCombinerThe combiner can combine several properties of the same edge into one properties at input step.

5.4 Worker Buffers

config optiondefault valuedescription
worker.received_buffers_bytes_limit104857600 (100 MB)The limit bytes of buffers of received data. The total size of all buffers can’t exceed this limit. If received buffers reach this limit, they will be merged into a file (spill to disk).
worker.write_buffer_capacity52428800 (50 MB)The initial size of write buffer that used to store vertex or message.
worker.write_buffer_threshold52428800 (50 MB)The threshold of write buffer. Exceeding it will trigger sorting. The write buffer is used to store vertex or message.

5.5 Worker Data & Timeouts

config optiondefault valuedescription
worker.data_dirs[jobs]The directories separated by ‘,’ that received vertices and messages can persist into.
worker.wait_sort_timeout600000 (10 minutes)The max timeout (in ms) for message-handler to wait for sort-thread to sort one batch of buffers.
worker.wait_finish_messages_timeout86400000 (24 hours)The max timeout (in ms) for message-handler to wait for finish-message of all workers.

6. I/O & Output Configuration

Configuration for output computation results.

6.1 Output Class & Result

config optiondefault valuedescription
output.output_classorg.apache.hugegraph.computer.core.output.LogOutputThe class to output the computation result of each vertex. Called after iteration computation.
output.result_namevalueThe value is assigned dynamically by #name() of instance created by WORKER_COMPUTATION_CLASS.
output.result_write_typeOLAP_COMMONThe result write-type to output to HugeGraph, allowed values: [OLAP_COMMON, OLAP_SECONDARY, OLAP_RANGE].

6.2 Output Behavior

config optiondefault valuedescription
output.with_adjacent_edgesfalseWhether to output the adjacent edges of the vertex.
output.with_vertex_propertiesfalseWhether to output the properties of the vertex.
output.with_edge_propertiesfalseWhether to output the properties of the edge.

6.3 Batch Output

config optiondefault valuedescription
output.batch_size500The batch size of output.
output.batch_threads1The number of threads used for batch output.
output.single_threads1The number of threads used for single output.

6.4 HDFS Output

config optiondefault valuedescription
output.hdfs_urlhdfs://127.0.0.1:9000The HDFS URL for output.
output.hdfs_userhadoopThe HDFS user for output.
output.hdfs_path_prefix/hugegraph-computer/resultsThe directory of HDFS output results.
output.hdfs_delimiter, (comma)The delimiter of HDFS output.
output.hdfs_merge_partitionstrueWhether to merge output files of multiple partitions.
output.hdfs_replication3The replication number of HDFS.
output.hdfs_core_site_path"" (empty)The HDFS core site path.
output.hdfs_site_path"" (empty)The HDFS site path.
output.hdfs_kerberos_enablefalseWhether Kerberos authentication is enabled for HDFS.
output.hdfs_kerberos_principal"" (empty)The HDFS principal for Kerberos authentication.
output.hdfs_kerberos_keytab"" (empty)The HDFS keytab file for Kerberos authentication.
output.hdfs_krb5_conf/etc/krb5.confKerberos configuration file path.

6.5 Retry & Timeout

config optiondefault valuedescription
output.retry_times3The retry times when output fails.
output.retry_interval10The retry interval (in seconds) when output fails.
output.thread_pool_shutdown_timeout60The timeout (in seconds) of output thread pool shutdown.

7. Network & Transport Configuration

Configuration for network communication between workers and master.

7.1 Server Configuration

config optiondefault valuedescription
transport.server_host127.0.0.1The hostname or IP that listens for transport data. This option is managed by the runtime system.
transport.server_port0The port that listens for transport data; 0 assigns a random port. This option is managed by the runtime system.
transport.server_threads4The number of transport threads for server.

7.2 Client Configuration

config optiondefault valuedescription
transport.client_threads4The number of transport threads for client.
transport.client_connect_timeout3000The timeout (in ms) of client connect to server.

7.3 Protocol Configuration

config optiondefault valuedescription
transport.provider_classorg.apache.hugegraph.computer.core.network.netty.NettyTransportProviderThe transport provider, currently only supports Netty.
transport.io_modeAUTOThe network IO mode, allowed values: [NIO, EPOLL, AUTO]. AUTO means selecting the appropriate mode automatically.
transport.tcp_keep_alivetrueWhether to enable TCP keep-alive.
transport.transport_epoll_ltfalseWhether to enable EPOLL level-trigger (only effective when io_mode=EPOLL).

7.4 Buffer Configuration

config optiondefault valuedescription
transport.send_buffer_size0The size of socket send-buffer in bytes. 0 means using system default value.
transport.receive_buffer_size0The size of socket receive-buffer in bytes. 0 means using system default value.
transport.write_buffer_high_mark67108864 (64 MB)The high water mark for write buffer in bytes. It will trigger sending unavailable if the number of queued bytes > write_buffer_high_mark.
transport.write_buffer_low_mark33554432 (32 MB)The low water mark for write buffer in bytes. It will trigger sending available if the number of queued bytes < write_buffer_low_mark.

7.5 Flow Control

config optiondefault valuedescription
transport.max_pending_requests8The max number of client unreceived ACKs. It will trigger sending unavailable if the number of unreceived ACKs >= max_pending_requests.
transport.min_pending_requests6The minimum number of client unreceived ACKs. It will trigger sending available if the number of unreceived ACKs < min_pending_requests.
transport.min_ack_interval200The minimum interval (in ms) of server reply ACK.

7.6 Timeouts

config optiondefault valuedescription
transport.close_timeout10000The timeout (in ms) of close server or close client.
transport.sync_request_timeout10000The timeout (in ms) to wait for response after sending sync-request.
transport.finish_session_timeout0The timeout (in ms) to finish session. 0 means using (transport.sync_request_timeout × transport.max_pending_requests).
transport.write_socket_timeout3000The timeout (in ms) to write data to socket buffer.
transport.server_idle_timeout360000 (6 minutes)The max timeout (in ms) of server idle.

7.7 Heartbeat

config optiondefault valuedescription
transport.heartbeat_interval20000 (20 seconds)The minimum interval (in ms) between heartbeats on client side.
transport.max_timeout_heartbeat_count120The maximum times of timeout heartbeat on client side. If the number of timeouts waiting for heartbeat response continuously > max_timeout_heartbeat_count, the channel will be closed from client side.

7.8 Advanced Network Settings

config optiondefault valuedescription
transport.max_syn_backlog511The capacity of SYN queue on server side. 0 means using system default value.
transport.recv_file_modetrueWhether to enable receive buffer-file mode. It will receive buffer and write to file from socket using zero-copy if enabled. Note: Requires OS support for zero-copy (e.g., Linux sendfile/splice).
transport.network_retries3The number of retry attempts for network communication if network is unstable.

8. Storage & Persistence Configuration

Configuration for HGKV (HugeGraph Key-Value) storage engine and value files.

8.1 HGKV Configuration

config optiondefault valuedescription
hgkv.max_file_size2147483648 (2 GB)The max number of bytes in each HGKV file.
hgkv.max_data_block_size65536 (64 KB)The max byte size of HGKV file data block.
hgkv.max_merge_files10The max number of files to merge at one time.
hgkv.temp_file_dir/tmp/hgkvThis folder is used to store temporary files during the file merging process.

8.2 Value File Configuration

config optiondefault valuedescription
valuefile.max_segment_size1073741824 (1 GB)The max number of bytes in each segment of value-file.

9. BSP & Coordination Configuration

Configuration for Bulk Synchronous Parallel (BSP) protocol and etcd coordination.

config optiondefault valuedescription
bsp.etcd_endpointshttp://localhost:2379The etcd endpoints; separate multiple addresses with commas. In K8s deployments, this option is set by the Operator.
bsp.max_super_step10 (packaged: 2)The max super step of the algorithm.
bsp.register_timeout300000 (packaged: 100000)The max timeout (in ms) to wait for master and workers to register.
bsp.wait_workers_timeout86400000 (24 hours)The max timeout (in ms) to wait for workers BSP event.
bsp.wait_master_timeout86400000 (24 hours)The max timeout (in ms) to wait for master BSP event.
bsp.log_interval30000 (30 seconds)The log interval (in ms) to print the log while waiting for BSP event.

10. Performance Tuning Configuration

Configuration for performance optimization.

config optiondefault valuedescription
allocator.max_vertices_per_thread10000Maximum number of vertices per thread processed in each memory allocator.
sort.thread_nums4The number of threads performing internal sorting.

11. System Administration Configuration

The following options are managed by the runtime system and should not be overridden in job configurations.

The following configuration items are automatically managed by the K8s Operator, Driver, or runtime system. Manual modification will cause cluster communication failures or job scheduling errors.

config optionmanaged bydescription
bsp.etcd_endpointsK8s OperatorAutomatically set to operator’s etcd service address
transport.server_hostRuntimeAutomatically set to pod/container hostname
transport.server_portRuntimeAutomatically assigned random port
job.namespaceK8s OperatorAutomatically set to job namespace
job.idK8s OperatorAutomatically set to job ID from CRD
job.workers_countK8s OperatorAutomatically set from CRD workerInstances
rpc.server_hostRuntimeRPC server hostname (system-managed)
rpc.server_portRuntimeRPC server port (system-managed)
rpc.remote_urlRuntimeRPC remote URL (system-managed)

Why These Are Forbidden:

  • BSP/RPC Configuration: Must match the actual deployed etcd/RPC services. Manual overrides break coordination.
  • Job Configuration: Must match K8s CRD specifications. Mismatches cause worker count errors.
  • Transport Configuration: Must use actual pod hostnames/ports. Manual values prevent inter-worker communication.

K8s Operator Config Options

NOTE: Option needs to be converted through environment variable settings, e.g. k8s.internal_etcd_url => INTERNAL_ETCD_URL

config optiondefault valuedescription
k8s.auto_destroy_podtrueWhether to automatically destroy all pods when the job is completed or failed.
k8s.close_reconciler_timeout120The max timeout (in ms) to close reconciler.
k8s.internal_etcd_urlhttp://127.0.0.1:2379The internal etcd URL for operator system.
k8s.max_reconcile_retry3The max retry times of reconcile.
k8s.probe_backlog50The maximum backlog for serving health probes.
k8s.probe_port9892The port that the controller binds to for serving health probes.
k8s.ready_check_internal1000The time interval (ms) of check ready.
k8s.ready_timeout30000The max timeout (in ms) of check ready.
k8s.reconciler_count10The max number of reconciler threads.
k8s.resync_period600000The minimum frequency at which watched resources are reconciled.
k8s.timezoneAsia/ShanghaiThe timezone of computer job and operator.
k8s.watch_namespacehugegraph-computer-systemThe namespace to watch custom resources in. Use ‘*’ to watch all namespaces.

HugeGraph-Computer CRD

CRD: https://github.com/apache/hugegraph-computer/blob/master/computer/computer-k8s-operator/manifest/hugegraph-computer-crd.v1.yaml

specdefault valuedescriptionrequired
algorithmNameThe name of algorithm.true
jobIdThe job id.true
imageThe image of algorithm.true
computerConfThe map of computer config options.true
workerInstancesThe number of worker instances, it will override the ‘job.workers_count’ option.true
pullPolicyAlwaysThe pull-policy of image, detail please refer to: https://kubernetes.io/docs/concepts/containers/images/#image-pull-policyfalse
pullSecretsThe pull-secrets of Image, detail please refer to: https://kubernetes.io/docs/concepts/containers/images/#specifying-imagepullsecrets-on-a-podfalse
masterCpuThe cpu limit of master, the unit can be ’m’ or without unit detail please refer to: https://kubernetes.io/docs/concepts/configuration/manage-resources-containers/#meaning-of-cpufalse
workerCpuThe cpu limit of worker, the unit can be ’m’ or without unit detail please refer to: https://kubernetes.io/docs/concepts/configuration/manage-resources-containers/#meaning-of-cpufalse
masterMemoryThe memory limit of master, the unit can be one of Ei、Pi、Ti、Gi、Mi、Ki detail please refer to: https://kubernetes.io/docs/concepts/configuration/manage-resources-containers/#meaning-of-memoryfalse
workerMemoryThe memory limit of worker, the unit can be one of Ei、Pi、Ti、Gi、Mi、Ki detail please refer to: https://kubernetes.io/docs/concepts/configuration/manage-resources-containers/#meaning-of-memoryfalse
log4jXmlThe content of log4j.xml for computer job.false
jarFileThe jar path of computer algorithm.false
remoteJarUriThe remote jar uri of computer algorithm, it will overlay algorithm image.false
jvmOptionsThe java startup parameters of computer job.false
envVarsplease refer to: https://kubernetes.io/docs/tasks/inject-data-application/define-interdependent-environment-variables/false
envFromplease refer to: https://kubernetes.io/docs/tasks/inject-data-application/define-environment-variable-container/false
masterCommandbin/start-computer.shThe run command of master, equivalent to ‘Entrypoint’ field of Docker.false
masterArgs["-r master", “-d k8s”]The run args of master, equivalent to ‘Cmd’ field of Docker.false
workerCommandbin/start-computer.shThe run command of worker, equivalent to ‘Entrypoint’ field of Docker.false
workerArgs["-r worker", “-d k8s”]The run args of worker, equivalent to ‘Cmd’ field of Docker.false
volumesPlease refer to: https://kubernetes.io/docs/concepts/storage/volumes/false
volumeMountsPlease refer to: https://kubernetes.io/docs/concepts/storage/volumes/false
secretPathsThe map of k8s-secret name and mount path.false
configMapPathsThe map of k8s-configmap name and mount path.false
podTemplateSpecPlease refer to: https://kubernetes.io/docs/reference/kubernetes-api/workload-resources/pod-template-v1/#PodTemplateSpecfalse
securityContextPlease refer to: https://kubernetes.io/docs/tasks/configure-pod-container/security-context/false

KubeDriver Config Options

config optiondefault valuedescription
k8s.build_image_bash_pathThe path of command used to build image.
k8s.enable_internal_algorithmtrueWhether enable internal algorithm.
k8s.framework_image_urlhugegraph/hugegraph-computer:latestThe image url of computer framework.
k8s.image_repository_passwordThe password for login image repository.
k8s.image_repository_registryThe address for login image repository.
k8s.image_repository_urlhugegraph/hugegraph-computerThe url of image repository.
k8s.image_repository_usernameThe username for login image repository.
k8s.internal_algorithm[pageRank]The name list of all internal algorithm. Note: Algorithm names use camelCase here (e.g., pageRank), but algorithm implementations return underscore_case (e.g., page_rank).
k8s.internal_algorithm_image_urlhugegraph/hugegraph-computer:latestThe image url of internal algorithm.
k8s.jar_file_dir/cache/jars/The directory where the algorithm jar will be uploaded.
k8s.kube_config~/.kube/configThe path of k8s config file.
k8s.log4j_xml_pathThe log4j.xml path for computer job.
k8s.namespacehugegraph-computer-systemThe namespace of hugegraph-computer system.
k8s.pull_secret_names[]The names of pull-secret for pulling image.

5 - HugeGraph Client

The Java and Go clients are maintained in the HugeGraph Toolchain repository, while the Python client is maintained in the HugeGraph-AI repository. Their installation methods and APIs differ; see the corresponding pages for details.

5.1 - HugeGraph-Java-Client

1 Overview

HugeGraph Java Client translates Java APIs into REST requests to HugeGraph Server. It supports managing schemas and graph data, executing Gremlin queries, and calling Traverser APIs. See the Client API for detailed interfaces; this page shows how to use the client in a Java project.

For other languages, use the Go Client or the Python Client maintained in the HugeGraph-AI repository.

2 What You Need

  • JDK 11 (used by the current CI; the source target remains Java 8)
  • Maven 3.6+

3 How To Use

The basic steps to use HugeGraph-Client are as follows:

  • Build a new Maven project by IDEA or Eclipse
  • Add HugeGraph-Client dependency in a pom file;
  • Create an object to invoke the interface of HugeGraph-Client

See the complete example in the following section for the detail.

4 Complete Example

4.1 Build New Maven Project

Using IDEA or Eclipse to create the project:

4.2 Add Hugegraph-Client Dependency In POM

<dependencies>
    <dependency>
        <groupId>org.apache.hugegraph</groupId>
        <artifactId>hugegraph-client</artifactId>
        <!-- Select a released version from the download page -->
        <version>1.7.0</version>
    </dependency>    
</dependencies>

Development versions of the client and server may differ. Check the corresponding release notes for compatibility before upgrading.

4.3 Example

4.3.1 SingleExample
import java.io.IOException;
import java.util.Iterator;
import java.util.List;

import org.apache.hugegraph.driver.GraphManager;
import org.apache.hugegraph.driver.GremlinManager;
import org.apache.hugegraph.driver.HugeClient;
import org.apache.hugegraph.driver.SchemaManager;
import org.apache.hugegraph.structure.constant.T;
import org.apache.hugegraph.structure.graph.Edge;
import org.apache.hugegraph.structure.graph.Path;
import org.apache.hugegraph.structure.graph.Vertex;
import org.apache.hugegraph.structure.gremlin.Result;
import org.apache.hugegraph.structure.gremlin.ResultSet;

public class SingleExample {

    public static void main(String[] args) throws IOException {
        // If connect failed will throw a exception.
        HugeClient hugeClient = HugeClient.builder("http://localhost:8080",
                                                   "DEFAULT",
                                                   "hugegraph")
                                          .configUser("username", "password")
                                          // This is an example. In a production environment, secure credentials should be used.
                                          .build();

        SchemaManager schema = hugeClient.schema();

        schema.propertyKey("name").asText().ifNotExist().create();
        schema.propertyKey("age").asInt().ifNotExist().create();
        schema.propertyKey("city").asText().ifNotExist().create();
        schema.propertyKey("weight").asDouble().ifNotExist().create();
        schema.propertyKey("lang").asText().ifNotExist().create();
        schema.propertyKey("date").asDate().ifNotExist().create();
        schema.propertyKey("price").asInt().ifNotExist().create();

        schema.vertexLabel("person")
              .properties("name", "age", "city")
              .primaryKeys("name")
              .ifNotExist()
              .create();

        schema.vertexLabel("software")
              .properties("name", "lang", "price")
              .primaryKeys("name")
              .ifNotExist()
              .create();

        schema.indexLabel("personByCity")
              .onV("person")
              .by("city")
              .secondary()
              .ifNotExist()
              .create();

        schema.indexLabel("personByAgeAndCity")
              .onV("person")
              .by("age", "city")
              .secondary()
              .ifNotExist()
              .create();

        schema.indexLabel("softwareByPrice")
              .onV("software")
              .by("price")
              .range()
              .ifNotExist()
              .create();

        schema.edgeLabel("knows")
              .sourceLabel("person")
              .targetLabel("person")
              .properties("date", "weight")
              .ifNotExist()
              .create();

        schema.edgeLabel("created")
              .sourceLabel("person").targetLabel("software")
              .properties("date", "weight")
              .ifNotExist()
              .create();

        schema.indexLabel("createdByDate")
              .onE("created")
              .by("date")
              .secondary()
              .ifNotExist()
              .create();

        schema.indexLabel("createdByWeight")
              .onE("created")
              .by("weight")
              .range()
              .ifNotExist()
              .create();

        schema.indexLabel("knowsByWeight")
              .onE("knows")
              .by("weight")
              .range()
              .ifNotExist()
              .create();

        GraphManager graph = hugeClient.graph();
        Vertex marko = graph.addVertex(T.LABEL, "person", "name", "marko",
                                       "age", 29, "city", "Beijing");
        Vertex vadas = graph.addVertex(T.LABEL, "person", "name", "vadas",
                                       "age", 27, "city", "Hongkong");
        Vertex lop = graph.addVertex(T.LABEL, "software", "name", "lop",
                                     "lang", "java", "price", 328);
        Vertex josh = graph.addVertex(T.LABEL, "person", "name", "josh",
                                      "age", 32, "city", "Beijing");
        Vertex ripple = graph.addVertex(T.LABEL, "software", "name", "ripple",
                                        "lang", "java", "price", 199);
        Vertex peter = graph.addVertex(T.LABEL, "person", "name", "peter",
                                       "age", 35, "city", "Shanghai");

        marko.addEdge("knows", vadas, "date", "2016-01-10", "weight", 0.5);
        marko.addEdge("knows", josh, "date", "2013-02-20", "weight", 1.0);
        marko.addEdge("created", lop, "date", "2017-12-10", "weight", 0.4);
        josh.addEdge("created", lop, "date", "2009-11-11", "weight", 0.4);
        josh.addEdge("created", ripple, "date", "2017-12-10", "weight", 1.0);
        peter.addEdge("created", lop, "date", "2017-03-24", "weight", 0.2);

        GremlinManager gremlin = hugeClient.gremlin();
        System.out.println("==== Path ====");
        ResultSet resultSet = gremlin.gremlin("g.V().outE().path()").execute();
        Iterator<Result> results = resultSet.iterator();
        results.forEachRemaining(result -> {
            System.out.println(result.getObject().getClass());
            Object object = result.getObject();
            if (object instanceof Vertex) {
                System.out.println(((Vertex) object).id());
            } else if (object instanceof Edge) {
                System.out.println(((Edge) object).id());
            } else if (object instanceof Path) {
                List<Object> elements = ((Path) object).objects();
                elements.forEach(element -> {
                    System.out.println(element.getClass());
                    System.out.println(element);
                });
            } else {
                System.out.println(object);
            }
        });

        hugeClient.close();
    }
}
4.3.2 BatchExample
import java.util.ArrayList;
import java.util.List;

import org.apache.hugegraph.driver.GraphManager;
import org.apache.hugegraph.driver.HugeClient;
import org.apache.hugegraph.driver.SchemaManager;
import org.apache.hugegraph.structure.graph.Edge;
import org.apache.hugegraph.structure.graph.Vertex;

public class BatchExample {

    public static void main(String[] args) {
        HugeClient hugeClient = HugeClient.builder("http://localhost:8080",
                                                   "DEFAULT",
                                                   "hugegraph")
                                          .configUser("username", "password")
                                          // This is an example. In a production environment, secure credentials should be used.
                                          .build();

        SchemaManager schema = hugeClient.schema();

        schema.propertyKey("name").asText().ifNotExist().create();
        schema.propertyKey("age").asInt().ifNotExist().create();
        schema.propertyKey("lang").asText().ifNotExist().create();
        schema.propertyKey("date").asDate().ifNotExist().create();
        schema.propertyKey("price").asInt().ifNotExist().create();

        schema.vertexLabel("person")
              .properties("name", "age")
              .primaryKeys("name")
              .ifNotExist()
              .create();

        schema.vertexLabel("person")
              .properties("price")
              .nullableKeys("price")
              .append();

        schema.vertexLabel("software")
              .properties("name", "lang", "price")
              .primaryKeys("name")
              .ifNotExist()
              .create();

        schema.indexLabel("softwareByPrice")
              .onV("software").by("price")
              .range()
              .ifNotExist()
              .create();

        schema.edgeLabel("knows")
              .link("person", "person")
              .properties("date")
              .ifNotExist()
              .create();

        schema.edgeLabel("created")
              .link("person", "software")
              .properties("date")
              .ifNotExist()
              .create();

        schema.indexLabel("createdByDate")
              .onE("created").by("date")
              .secondary()
              .ifNotExist()
              .create();

        // get schema object by name
        System.out.println(schema.getPropertyKey("name"));
        System.out.println(schema.getVertexLabel("person"));
        System.out.println(schema.getEdgeLabel("knows"));
        System.out.println(schema.getIndexLabel("createdByDate"));

        // list all schema objects
        System.out.println(schema.getPropertyKeys());
        System.out.println(schema.getVertexLabels());
        System.out.println(schema.getEdgeLabels());
        System.out.println(schema.getIndexLabels());

        GraphManager graph = hugeClient.graph();

        Vertex marko = new Vertex("person").property("name", "marko")
                                           .property("age", 29);
        Vertex vadas = new Vertex("person").property("name", "vadas")
                                           .property("age", 27);
        Vertex lop = new Vertex("software").property("name", "lop")
                                           .property("lang", "java")
                                           .property("price", 328);
        Vertex josh = new Vertex("person").property("name", "josh")
                                          .property("age", 32);
        Vertex ripple = new Vertex("software").property("name", "ripple")
                                              .property("lang", "java")
                                              .property("price", 199);
        Vertex peter = new Vertex("person").property("name", "peter")
                                           .property("age", 35);

        Edge markoKnowsVadas = new Edge("knows").source(marko).target(vadas)
                                                .property("date", "2016-01-10");
        Edge markoKnowsJosh = new Edge("knows").source(marko).target(josh)
                                               .property("date", "2013-02-20");
        Edge markoCreateLop = new Edge("created").source(marko).target(lop)
                                                 .property("date",
                                                           "2017-12-10");
        Edge joshCreateRipple = new Edge("created").source(josh).target(ripple)
                                                   .property("date",
                                                             "2017-12-10");
        Edge joshCreateLop = new Edge("created").source(josh).target(lop)
                                                .property("date", "2009-11-11");
        Edge peterCreateLop = new Edge("created").source(peter).target(lop)
                                                 .property("date",
                                                           "2017-03-24");

        List<Vertex> vertices = new ArrayList<>();
        vertices.add(marko);
        vertices.add(vadas);
        vertices.add(lop);
        vertices.add(josh);
        vertices.add(ripple);
        vertices.add(peter);

        List<Edge> edges = new ArrayList<>();
        edges.add(markoKnowsVadas);
        edges.add(markoKnowsJosh);
        edges.add(markoCreateLop);
        edges.add(joshCreateRipple);
        edges.add(joshCreateLop);
        edges.add(peterCreateLop);

        vertices = graph.addVertices(vertices);
        vertices.forEach(vertex -> System.out.println(vertex));

        edges = graph.addEdges(edges, false);
        edges.forEach(edge -> System.out.println(edge));

        hugeClient.close();
    }
}

4.4 Run The Example

Before running Example, you need to start the Server. For the startup process, seeHugeGraph-Server Quick Start.

4.5 More Information About Client-API

SeeIntroduce basic API of HugeGraph-Client.

5.2 - HugeGraph Python Client Quick Start

hugegraph-python-client is the Python SDK for HugeGraph. It manages schemas, reads and writes graph data, and executes Gremlin queries. HugeGraph-LLM and HugeGraph-ML also use this client.

The module lives in the hugegraph-ai repository under hugegraph-python-client/. The import name is pyhugegraph.

Requirements

  • Python 3.9 or later for the client itself. The HugeGraph-AI workspace requires Python 3.10 or later, and CI runs the client tests on 3.10 and 3.11.
  • HugeGraph Server 1.5.0 or later. The client refuses to connect to older servers; use client v1.3.x for those.
  • uv (recommended) or pip

Runtime dependencies are decorator, requests, setuptools, urllib3 and rich.

Installation

The released package is published on PyPI as hugegraph-python:

uv pip install hugegraph-python
# Alternatively: pip install hugegraph-python

The PyPI release lags behind the repository. In the source tree the distribution is declared as hugegraph-python-client and versioned with the rest of HugeGraph-AI, so install from source if you need the newest code.

To use the latest repository code, sync the workspace from the root of the HugeGraph-AI repository. hugegraph-python-client is a workspace member exposed through the python-client extra, so plain uv sync does not pull it in:

git clone https://github.com/apache/hugegraph-ai.git
cd hugegraph-ai
uv sync --extra python-client
source .venv/bin/activate

Connect and Write Data

from pyhugegraph.client import PyHugeClient

client = PyHugeClient(
    url="http://127.0.0.1:8080",
    graph="hugegraph",
    user="admin",
    pwd="admin",
    graphspace=None,
)

schema = client.schema()
schema.propertyKey("name").asText().ifNotExist().create()
schema.propertyKey("birthDate").asText().ifNotExist().create()
schema.vertexLabel("Person").properties("name", "birthDate") \
      .usePrimaryKeyId().primaryKeys("name").ifNotExist().create()
schema.vertexLabel("Movie").properties("name") \
      .usePrimaryKeyId().primaryKeys("name").ifNotExist().create()
schema.edgeLabel("ActedIn").sourceLabel("Person").targetLabel("Movie") \
      .ifNotExist().create()

graph = client.graph()
person = graph.addVertex(
    "Person", {"name": "Al Pacino", "birthDate": "1940-04-25"}
)
movie = graph.addVertex("Movie", {"name": "The Godfather"})
edge = graph.addEdge("ActedIn", person.id, movie.id, {})

print(graph.getVertexById(person.id))
print(graph.getEdgeById(edge.id))
graph.close()

Client Parameters

PyHugeClient(url, graph, user, pwd, graphspace=None, timeout=None)

ParameterTypeDefaultDescription
urlstrrequiredBase URL of HugeGraph Server. If the value has no scheme, http:// is prepended, so 127.0.0.1:8080 also works.
graphstrrequiredGraph name. This is the second positional parameter.
userstrrequiredUsername, sent as HTTP basic auth.
pwdstrrequiredPassword, sent as HTTP basic auth.
graphspacestr or NoneNoneGraphSpace name. See below for how None is resolved.
timeouttuple[float, float] or NoneNone(connect, read) timeouts in seconds. None becomes (0.5, 15.0).

Every HTTP session retries three times with a 0.1 backoff factor on 500, 502 and 504 responses.

Server Version and GraphSpace

The client resolves GraphSpace at construction time:

  • A non-empty graphspace string turns GraphSpace mode on directly.
  • Otherwise the client sends GET {url}/versions and reads versions.core.
  • A server older than 1.5.0 raises RuntimeError asking you to upgrade the server or use client v1.3.x.
  • A server newer than 1.5.0 gets graphspace set to DEFAULT and GraphSpace mode turned on, with a warning in the log. A server at exactly 1.5.0 keeps GraphSpace mode off.
  • If the probe fails for network reasons, GraphSpace mode stays off.

The mode decides the request prefix: /graphspaces/<graphspace>/graphs/<graph>/... when GraphSpace is on, /graphs/<graph>/... when it is off.

Managers on the Client

Each accessor builds its manager lazily and gives it a dedicated HTTP session.

AccessorManagerCovers
client.schema()SchemaManagerProperty keys, vertex labels, edge labels, index labels
client.graph()GraphManagerVertex and edge CRUD, batch writes, paging
client.gremlin()GremlinManagerGremlin execution
client.graphs()GraphsManagerGraph list, graph info, config, clear data
client.traverser()TraverserManagerTraversal and path algorithms
client.variable()VariableManagerGraph variables
client.task()TaskManagerAsync task list, query, cancel, delete
client.auth()AuthManagerUsers, groups, targets, belongs, accesses
client.metrics()MetricsManagerServer metrics
client.version()VersionManagerServer version

RankManager, RebuildManager and ServicesManager also ship in pyhugegraph.api, but PyHugeClient does not expose accessors for them yet; construct them directly with a session if you need them.

Common Operations

Build the Schema

The schema builders are fluent. Call create() last, or append(), eliminate() and remove() to change an existing definition.

schema = client.schema()

# Property keys: asText/asInt/asLong/asFloat/asDouble/asBool/asByte/asBlob/asDate/asObject
# cardinality: valueSingle/valueList/valueSet
# aggregation: calcMax/calcMin/calcSum/calcOld
schema.propertyKey("age").asInt().valueSingle().ifNotExist().create()

# Vertex labels: useAutomaticId/useCustomizeStringId/useCustomizeNumberId/usePrimaryKeyId
schema.vertexLabel("person").properties("name", "age", "city") \
      .primaryKeys("name").nullableKeys("city").ifNotExist().create()

# Edge labels: link() is shorthand for sourceLabel() plus targetLabel()
schema.edgeLabel("knows").link("person", "person").multiTimes() \
      .properties("date", "city").sortKeys("date").nullableKeys("city") \
      .ifNotExist().create()

# Index labels: onV/onE, then secondary/range/search/shard/unique
schema.indexLabel("personByCity").onV("person").by("city") \
      .secondary().ifNotExist().create()

Query the Schema

schema = client.schema()
print(schema.getSchema())            # whole schema, format defaults to "json"
print(schema.getPropertyKeys())
print(schema.getVertexLabels())
print(schema.getEdgeLabels())
print(schema.getIndexLabels())

# Single definitions
print(schema.getPropertyKey("name"))
print(schema.getVertexLabel("person"))
print(schema.getEdgeLabel("knows"))
print(schema.getIndexLabel("personByCity"))

# Edge label links, formatted as "Person--ActedIn-->Movie"
print(schema.getRelations())

Read, Update and Delete Graph Data

The graph API takes property dictionaries, not chained property builders:

graph = client.graph()
graph.appendVertex(person.id, {"birthDate": "1940-04-25"})    # add properties
graph.eliminateVertex(person.id, {"birthDate": "1940-04-25"}) # drop properties
graph.appendEdge(edge.id, {"city": "Beijing"})
graph.eliminateEdge(edge.id, {"city": "Beijing"})
graph.removeEdgeById(edge.id)
graph.removeVertexById(person.id)
graph.close()

addVertex returns a VertexData with id, label, type and properties. addEdge returns an EdgeData with id, label, type, outV, outVLabel, inV, inVLabel and properties.

Vertex ids passed to the client may be strings, integers or uuid.UUID values. Booleans are rejected, and integers must fit the Java signed long range.

Batch Writes

addVertices takes (label, properties) pairs, and addEdges takes (label, out_id, in_id, out_label, in_label, properties) tuples. Both return objects that carry only the generated ids.

graph = client.graph()
vertices = graph.addVertices([
    ("person", {"name": "Alice", "age": 20}),
    ("person", {"name": "Bob", "age": 23}),
])
edges = graph.addEdges([
    ("knows", vertices[0].id, vertices[1].id, "person", "person", {"date": "2012-01-10"}),
])

Paging and Conditional Queries

graph = client.graph()

# Returns (vertices, next_page); pass next_page back in to continue
vertices, next_page = graph.getVertexByPage("person", limit=10)
vertices, next_page = graph.getVertexByPage("person", limit=10, page=next_page)

# Server-side property predicates
older = graph.getVertexByCondition("person", properties={"age": "P.gt(29)"})

# Edges by page. When vertex_id is given, direction is required
edges, next_page = graph.getEdgeByPage(label="knows", limit=10)
edges, next_page = graph.getEdgeByPage(vertex_id=person.id, direction="OUT", limit=10)

# Batch lookup by id
graph.getVerticesById([v1.id, v2.id])
graph.getEdgesById([e1.id, e2.id])

Execute Gremlin

gremlin = client.gremlin()
result = gremlin.exec("g.V().limit(5)")
print(result)

exec binds the graph and g aliases for you, based on the graph name and the resolved GraphSpace, and returns the result field of the server response. A response missing requestId, status or result raises ResponseParseError.

Traverse the Graph

TraverserManager wraps the server traverser endpoints. Its methods use snake_case.

traverser = client.traverser()

traverser.k_out(marko_id, 2)
traverser.k_neighbor(marko_id, 2)
traverser.same_neighbors(marko_id, josh_id)
traverser.jaccard_similarity(marko_id, josh_id)
traverser.shortest_path(marko_id, ripple_id, 3)
traverser.all_shortest_paths(marko_id, ripple_id, 3)
traverser.weighted_shortest_path(marko_id, ripple_id, "weight", 3)
traverser.single_source_shortest_path(marko_id, 2)
traverser.multi_node_shortest_path([marko_id, josh_id], max_depth=2)
traverser.paths(marko_id, josh_id, 2)
traverser.crosspoints(marko_id, josh_id, 2)
traverser.rings(marko_id, 3)
traverser.rays(marko_id, 2)
traverser.vertices(marko_id)
traverser.edges(edge_id)

The POST-based variants take request bodies: advanced_paths, customized_paths, template_paths, customized_crosspoints and fusiform_similarity.

Graph Variables

variable = client.variable()
variable.set("owner", "mary")
print(variable.get("owner"))
print(variable.all())
variable.remove("owner")

Async Tasks

task = client.task()
print(task.list_tasks(status="success", limit=10))
print(task.get_task(task_id))
task.cancel_task(task_id)
task.delete_task(task_id)

Server Metrics and Graph Info

metrics = client.metrics()
metrics.get_all_basic_metrics()
metrics.get_gauges_metrics()
metrics.get_counters_metrics()
metrics.get_histograms_metrics()
metrics.get_meters_metrics()
metrics.get_timers_metrics()
metrics.get_statistics_metrics()
metrics.get_system_metrics()
metrics.get_backend_metrics()

graphs = client.graphs()
graphs.get_all_graphs()
graphs.get_version()
graphs.get_graph_info()
graphs.get_graph_config()
graphs.clear_graph_all_data()   # deletes every vertex, edge and schema entry

print(client.version().version())

Authentication and Authorization

AuthManager follows the server routing: users, targets, belongs and accesses are mounted under /graphspaces/{graphspace}/auth/..., while groups stay at the server-level /auth/groups. On HugeGraph 1.7.0 and later a graphspace must be resolved, otherwise these calls raise ValueError before any request is sent.

auth = client.auth()

user = auth.create_user("test_user", "password")
auth.modify_user(user["id"], user_email="hugegraph@apache.org")
auth.get_user(user["id"])
auth.list_users(limit=10)
auth.delete_user(user["id"])

group = auth.create_group("test_group", "read only")
auth.modify_group(group["id"], group_description="updated")
auth.list_groups()
auth.delete_group(group["id"])

target = auth.create_target("target1", "hugegraph", "127.0.0.1:8080", [])
auth.update_target(target["id"], "target1", "hugegraph", "127.0.0.1:8080", [])
auth.list_targets()
auth.delete_target(target["id"])

belong = auth.create_belong(user["id"], group["id"])
auth.update_belong(belong["id"], "description")
auth.list_belongs()
auth.delete_belong(belong["id"])

access = auth.grant_accesses(group["id"], target["id"], "READ")
auth.modify_accesses(access["id"], "description")
auth.list_accesses()
auth.revoke_accesses(access["id"])

Method Naming

Manager methods written in camelCase, such as addVertex and getVertexById, also get a snake_case alias generated at construction time. graph.add_vertex(...) and graph.addVertex(...) reach the same method. The camelCase spellings are marked deprecated in the debug log, so prefer snake_case in new code.

Error Handling

Exceptions live in pyhugegraph.utils.exceptions:

ExceptionRaised when
NotAuthorizedErrorThe server answers 401
NotFoundErrorThe server answers 404, or a required argument is missing
ServerErrorAny other non-2xx response, with the server message attached
ResponseParseErrorA successful response cannot be parsed into the expected shape
ServiceUnavailableErrorThe server reports ServiceUnavailableException
InvalidParameterError, CreateError, RemoveError, UpdateError, DataFormatErrorRaised by individual builders and structures

Request and response bodies are logged with password, token and secret values redacted.

from pyhugegraph.utils.exceptions import NotFoundError

try:
    graph.getVertexById("no-such-id")
except NotFoundError:
    print("vertex missing")

API parameters may change with the HugeGraph REST API version. If an interface is incompatible, first check the REST API documentation for the current server version and the client test cases.

Development Checks

Run formatting and static checks from the root of the HugeGraph-AI repository:

./style/code_format_and_analysis.sh

Run the tests the same way CI does:

# Unit and contract tests, no server needed
uv run pytest hugegraph-python-client/src/tests -m "unit or contract"

# Integration tests against a running server
HUGEGRAPH_URL=http://127.0.0.1:8080 \
HUGEGRAPH_GRAPH=hugegraph \
HUGEGRAPH_USER=admin \
HUGEGRAPH_PASSWORD=admin \
uv run pytest hugegraph-python-client/src/tests -m "integration and hugegraph"

CI runs the integration job against the hugegraph/hugegraph:1.7.0 image. HUGEGRAPH_GRAPHSPACE is also read when you need a non-default space.

The source code and tests are under hugegraph-python-client/src/pyhugegraph/ and hugegraph-python-client/src/tests/. A runnable example is at hugegraph-python-client/src/pyhugegraph/example/hugegraph_example.py.

5.3 - HugeGraph Go Client Quick Start

HugeGraph Go Client is the Go SDK in the Toolchain repository. It currently provides APIs for version queries, schemas (property keys, vertex labels, and edge labels), vertices, and Gremlin. An edge data API is not implemented yet.

This module is still under development. Refer to the source code under hugegraph-client-go/api/v1 for the currently available interfaces.

Requirements

  • Go 1.19 or later
  • An accessible HugeGraph Server; examples use http://127.0.0.1:8080

Installation

Run the following command in a Go module project:

go get github.com/apache/hugegraph-toolchain/hugegraph-client-go

Initialize the Client

NewCommonClient requires Host to be an IP address and Port to be between 1 and 65535. The client always connects over plain HTTP. Leave the username and password empty when authentication is disabled; Basic Auth is sent only when both are set.

GraphSpace is applied only by the Vertex API, which then calls /graphspaces/{space}/graphs/{graph}/..., and by the default Gremlin aliases (an empty value is treated as DEFAULT). The schema entry points and Version() always call /graphs/{graph}/... and /versions, regardless of GraphSpace. Use DEFAULT for the default space; leaving GraphSpace empty makes the Vertex API fall back to the /graphs/{graph} path used by older servers.

package main

import (
	"fmt"
	"log"

	hugegraph "github.com/apache/hugegraph-toolchain/hugegraph-client-go"
)

func main() {
	client, err := hugegraph.NewCommonClient(hugegraph.Config{
		Host:       "127.0.0.1",
		Port:       8080,
		GraphSpace: "DEFAULT",
		Graph:      "hugegraph",
		Username:   "",
		Password:   "",
	})
	if err != nil {
		log.Fatal(err)
	}

	response, err := client.Version()
	if err != nil {
		log.Fatal(err)
	}
	defer response.Body.Close()

	fmt.Println(response.Versions.Version)
}

The Versions value returned by Version() includes the HugeGraph Server, Core, Gremlin, and REST API versions. The NewDefaultCommonClient() helper in the source connects to the hugegraph graph at 127.0.0.1:8080 with admin/pa authentication and a ColorLogger that prints every request and response body. Production code should normally pass an explicit configuration instead.

Configuration Options

hugegraph.Config has the following fields:

FieldTypeDescription
HoststringHugeGraph Server IP address. Host names are rejected.
PortintHugeGraph Server REST port, 1 to 65535
GraphSpacestringGraph space; only used by the Vertex API and the default Gremlin aliases. Set an empty string when not needed.
GraphstringGraph name configured on the server
UsernamestringServer username; empty string when authentication is disabled
PasswordstringServer password; empty string when authentication is disabled
Transporthttp.RoundTripperCustom HTTP transport; http.DefaultTransport when nil
Loggerhgtransport.LoggerRequest/response logger; no logging when nil

The hgtransport package ships four loggers: TextLogger (plain text), ColorLogger (terminal colors), CurlLogger (runnable curl commands), and JSONLogger (JSON lines). Each has the same fields: Output (an io.Writer), EnableRequestBody, and EnableResponseBody.

import (
	"os"

	hugegraph "github.com/apache/hugegraph-toolchain/hugegraph-client-go"
	"github.com/apache/hugegraph-toolchain/hugegraph-client-go/hgtransport"
)

client, err := hugegraph.NewCommonClient(hugegraph.Config{
	Host:  "127.0.0.1",
	Port:  8080,
	Graph: "hugegraph",
	Logger: &hgtransport.ColorLogger{
		Output:             os.Stdout,
		EnableRequestBody:  true,
		EnableResponseBody: true,
	},
})

Available Entry Points

CommonClient currently exposes the following entry points:

Entry pointPurpose
Version()Query the server version
Schema()Query the complete schema
PropertykeyCreate, GetAll, GetByName, UpdateUserdata, DeleteByName
VertexLabelCreate, GetAll, GetByName, UpdateUserdata, DeleteByName
EdgeLabelCreate, GetAll, DeleteByName
VertexCreate, BatchCreate, UpdateProperties (with WithAction: append or eliminate)
GremlinGet and Post. Post defaults language to gremlin-groovy, fills the graph/g aliases from GraphSpace and Graph, and returns the parsed result in Data. Get only returns the status code and prints the raw response to stdout.

Each operation takes functional options named With... on the operation itself, for example client.Gremlin.Post.WithGremlin(...) or client.Propertykey.GetByName.WithName(...).

resp, err := client.Gremlin.Post(
	client.Gremlin.Post.WithGremlin("g.V().limit(3)"),
)
if err != nil {
	log.Fatal(err)
}
fmt.Println(resp.StatusCode, resp.Data.Status.Code, resp.Data.Result.Data)

The Vertex operations take model.Vertex[any] values from the internal/model package. Go does not allow importing an internal package from another module, so at the moment the Vertex API can only be called from code inside the client module itself; its test file is also fully commented out.

For complete usage, see the tests in each API directory, such as version_test.go, gemlin_test.go, and vertexlabel_test.go.