vonwenm/go-zmq

ZeroMQ bindings for Go

go-zmq

Go (golang) bindings for ZeroMQ (zmq, 0mq), currently built for ZeroMQ 3.2.x. Pull requests welcome.

View the API docs here.

Basic Usage

Import go-zmq:

import "github.com/vaughan0/go-zmq"

Create a new ZeroMQ Context and Socket:

ctx, err := zmq.NewContext()
if err != nil {
  panic(err)
}
defer ctx.Close()

Bind to a local endpoint:

sock, err := ctx.Socket(zmq.Rep)
if err != nil {
  panic(err)
}
defer sock.Close()

if err = sock.Bind("tcp://*:5555"); err != nil {
  panic(err)
}

Receive and send messages:

for {
  parts, err := sock.Recv()
  if err != nil {
    panic(err)
  }
  response := fmt.Sprintf("Received %d message parts", len(parts))
  if err = sock.Send([][]byte{
    []byte(response),
  }); err != nil {
    panic(err)
  }
}

Using Channels

ZeroMQ sockets are not thread-safe, which would make any ambitious ZeroMQ-using gopher sad. Luckily go-zmq provides a (thread-safe) way to use sockets with native Go channels. This also allows one to use the select construct with ZeroMQ sockets.

Start by using the Channels() method of a socket:

chans := sock.Channels()
defer chans.Close()

Now you can send and receive messages using the channels returned by chans.Out() and chans.In(), respectively. Don't forget to also check chans.Errors() to see if any errors occur.

for {
  select {
  case msg := <-chans.In():
    go func() {
      resp := doSomething(msg)
      chans.Out() <- resp
    }()
  case err := <-chans.Errors():
    panic(err)
  }
}