vesoft-inc / nebula-go

Nebula client in Golang
Apache License 2.0
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nebula-go

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IMPORTANT: Code of Nebula go client has been transferred from nebula-clients to this repository(nebula-go), and new releases in the future will be published in this repository. Please update your go.mod and imports correspondingly.

Official Nebula Go client which communicates with the server using fbthrift. Currently the latest stable release is v3.4.0

The code in master branch will be updated to accommodate the nightly changes made in NebulaGraph. To Use the console with a stable release of NebulaGraph, please check the branches and use the corresponding version.

Client version Nebula Service Version
v1.0.0 1.x.x
v2.0.0-ga 2.0.0-ga, 2.0.1
v2.5.1 2.5.0
v2.6.0 2.6.0
v3.0.0 3.0.0
v3.1.x 3.1.x
v3.2.x 3.1.x-3.2.x
v3.3.x 3.1.x-3.3.x
v3.4.x 3.1.x-3.4.x
v3.5.x 3.1.x-3.5.x
master 3.x-nightly

Please be careful not to modify the files in the nebula directory, these codes were all generated by fbthrift.

NOTE Installing Nebula Go v2.5.0 could cause checksum mismatch, use v2.5.1 instead.

Install & Update

$ go get -u -v github.com/vesoft-inc/nebula-go/v3@master

You can specify the version of Nebula-go by substituting <tag> in $ go get -u -v github.com/vesoft-inc/nebula-go@<tag>. For example:

for v3: $ go get -u -v github.com/vesoft-inc/nebula-go/v3@v3.4.0

for v2: $ go get -u -v github.com/vesoft-inc/nebula-go/v2@v2.6.0

Note: You will get a message like this if you don't specify a tag:

$ go get -u -v github.com/vesoft-inc/nebula-go/v2@master
go: github.com/vesoft-inc/nebula-go/v2 master => v2.0.0-20210506025434-97d4168c5c4d

Here the 20210506025434-97d4168c5c4d is a version tag auto-generated by GitHub using commit date and SHA. This should match the latest commit in the master branch.

Usage example

Mininal example

Suppose you already initialized your space and defined the schema as:

  1. Vertex person with properties name: string, age: int
  2. Edge like with properties likeness: double

You can query the Nebula by the minimal example:

package main

import (
  nebula "github.com/vesoft-inc/nebula-go/v3"
)

type Person struct {
  Name     string  `nebula:"name"`
  Age      int     `nebula:"age"`
  Likeness float64 `nebula:"likeness"`
}

func main() {
  hostAddress := nebula.HostAddress{Host: "127.0.0.1", Port: 3699}

  config, err := nebula.NewSessionPoolConf(
    "user",
    "password",
    []nebula.HostAddress{hostAddress},
    "space_name",
  )

  sessionPool, err := nebula.NewSessionPool(*config, nebula.DefaultLogger{})

  query := `GO FROM 'Bob' OVER like YIELD
    $^.person.name AS name,
    $^.person.age AS age,
    like.likeness AS likeness`

  resultSet, err := sessionPool.Execute(query)
  if err != nil {
    panic(err)
  }

  var personList []Person
  resultSet.Scan(&personList)
}

More examples

Simple Code Example

Code Example with Goroutines

Session Pool Example

There are some limitations while using the session pool:

  1. There MUST be an existing space in the DB before initializing the session pool.
  2. Each session pool is corresponding to a single USER and a single Space. This is to ensure that the user's access control is consistent. i.g. The same user may have different access privileges in different spaces. If you need to run queries in different spaces, you may have multiple session pools.
  3. Every time when sessionPool.Execute() is called, the session will execute the query in the space set in the session pool config.
  4. Commands that alter passwords or drop users should NOT be executed via session pool.

Code of Conduct

This project and everyone participating in it is governed by the Vesoft Code of Conduct. By participating, you are expected to uphold this code.

Licensing

Nebula GO is under Apache 2.0 license, so you can freely download, modify, and deploy the source code to meet your needs. You can also freely deploy Nebula GO as a back-end service to support your SaaS deployment.