golang socket.io client and server
Latest commit 098f1cc Dec 25, 2016 @graarh committed on GitHub Merge pull request #8 from penguinpowernz/patch-1
Would you double licence?


golang socket.io

golang implementation of socket.io library, client and server

You can check working chat server, based on this library, at http://funstream.tv

Examples directory contains simple client and server.


go get github.com/graarh/golang-socketio

Simple server usage

    server := gosocketio.NewServer(transport.GetDefaultWebsocketTransport())

    //handle connected
    server.On(gosocketio.OnConnection, func(c *gosocketio.Channel) {
        log.Println("New client connected")
        //join them to room

    type Message struct {
        Name string `json:"name"`
        Message string `json:"message"`

    //handle custom event
    server.On("send", func(c *gosocketio.Channel, msg Message) string {
        //send event to all in room
        c.BroadcastTo("chat", "message", msg)
        return "OK"

    //setup http server
    serveMux := http.NewServeMux()
    serveMux.Handle("/socket.io/", server)
    log.Panic(http.ListenAndServe(":80", serveMux))

Javascript client for this server

var socket = io('ws://yourdomain.com', {transports: ['websocket']});

    // listen for messages
    socket.on('message', function(message) {

        console.log('new message');

    socket.on('connect', function () {

        console.log('socket connected');

        //send something
        socket.emit('send', {name: "my name", message: "hello"}, function(result) {

            console.log('sended successfully');

Server, detailed usage

    //create server instance, you can setup transport parameters or get the default one
    //look at websocket.go for parameters description
    server := gosocketio.NewServer(transport.GetDefaultWebsocketTransport())

    // --- this is default handlers

    //on connection handler, occurs once for each connected client
    server.On(gosocketio.OnConnection, func(c *gosocketio.Channel, args interface{}) {
        //client id is unique
        log.Println("New client connected, client id is ", c.Id())

        //you can join clients to rooms
        c.Join("room name")

        //of course, you can list the clients in the room, or account them
        channels := c.List(data.Channel)
        //or check the amount of clients in room
        amount := c.Amount(data.Channel)
        log.Println(amount, "clients in room")
    //on disconnection handler, if client hangs connection unexpectedly, it will still occurs
    //you can omit function args if you do not need them
    //you can return string value for ack, or return nothing for emit
    server.On(gosocketio.OnDisconnection, func(c *gosocketio.Channel) {
        //this is not necessary, client will be removed from rooms
        //automatically on disconnect
        //but you can remove client from room whenever you need to
        c.Leave("room name")

    //error catching handler
    server.On(gosocketio.OnError, func(c *gosocketio.Channel) {
        log.Println("Error occurs")

    // --- this is custom handler

    //custom event handler
    server.On("handle something", func(c *gosocketio.Channel, channel Channel) string {
        log.Println("Something successfully handled")

        //you can return result of handler, in this case
        //handler will be converted from "emit" to "ack"
        return "result"

    //you can get client connection by it's id
    channel, _ := server.GetChannel("client id here")
    //and send the event to the client
    type MyEventData struct {
        Data: string
    channel.Emit("my event", MyEventData{"my data"})

    //or you can send ack to client and get result back
    result, err := channel.Ack("my custom ack", MyEventData{"ack data"}, time.Second * 5)

    //you can broadcast to all clients
    server.BroadcastToAll("my event", MyEventData{"broadcast"})

    //or for clients joined to room
    server.BroadcastTo("my room", "my event", MyEventData{"room broadcast"})

    //setup http server like this for handling connections
    serveMux := http.NewServeMux()
    serveMux.Handle("/socket.io/", server)
    log.Panic(http.ListenAndServe(":80", serveMux))


    //connect to server, you can use your own transport settings
    c, err := gosocketio.Dial(
        gosocketio.GetUrl("localhost", 80, false),

    //do something, handlers and functions are same as server ones

    //close connection


  1. Tests
  2. Travis CI
  3. http longpoll transport
  4. pure http (short-timed queries) transport
  5. binary format


Double licensed under GPL3 and MIT so you can use whichever you please.