sacoo7 / gowebsocket

Gorilla websockets based simplified websocket-client implementation in GO.

GoWebsocket

Gorilla websocket based simplified client implementation in GO.

Overview

This client provides following easy to implement functionality

• Support for emitting and receiving text and binary data
• Data compression
• Concurrency control
• Proxy support
• Setting request headers
• Subprotocols support
• SSL verification enable/disable

To install use

    go get github.com/sacOO7/gowebsocket

Description

Create instance of Websocket by passing url of websocket-server end-point

    //Create a client instance
    socket := gowebsocket.New("ws://echo.websocket.org/")
    

Important Note : url to websocket server must be specified with either ws or wss.

Connecting to server

• For connecting to server:

    //This will send websocket handshake request to socketcluster-server
    socket.Connect()

Registering All Listeners

    package main
    
    import (
    	"log"
    	"github.com/sacOO7/gowebsocket"
        "os"
        "os/signal"
    )
    
    func main() {
    
        interrupt := make(chan os.Signal, 1)
        signal.Notify(interrupt, os.Interrupt)
        
    	socket := gowebsocket.New("ws://echo.websocket.org/");
    	
    	socket.OnConnected = func(socket gowebsocket.Socket) {
    		log.Println("Connected to server");
    	};
    	
        socket.OnConnectError = func(err error, socket gowebsocket.Socket) {
            log.Println("Received connect error ", err)
        };
        
    	socket.OnTextMessage = func(message string, socket gowebsocket.Socket) {
    		log.Println("Received message " + message)
    	};
    	
    	socket.OnBinaryMessage = func(data [] byte, socket gowebsocket.Socket) {
            log.Println("Received binary data ", data)
        };
        
    	socket.OnPingReceived = func(data string, socket gowebsocket.Socket) {
    		log.Println("Received ping " + data)
    	};
    	
    	socket.OnPongReceived = func(data string, socket gowebsocket.Socket) {
            log.Println("Received pong " + data)
        };
        
    	socket.OnDisconnected = func(err error, socket gowebsocket.Socket) {
    		log.Println("Disconnected from server ")
    		return
    	};
    	
    	socket.Connect()
    	
        for {
            select {
            case <-interrupt:
                log.Println("interrupt")
                socket.Close()
                return
            }
        }
    }
    

Sending Text message

    socket.SendText("Hi there, this is my sample test message")

Sending Binary data

    token := make([]byte, 4)
    // rand.Read(token) putting some random value in token
    socket.SendBinary(token)

Closing the connection with server

    socket.Close()

Setting request headers

	socket.RequestHeader.Set("Accept-Encoding","gzip, deflate, sdch")
	socket.RequestHeader.Set("Accept-Language","en-US,en;q=0.8")
	socket.RequestHeader.Set("Pragma","no-cache")
	socket.RequestHeader.Set("User-Agent","Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.87 Safari/537.36")
	

Setting proxy server

• It can be set using connectionOptions by providing url to proxy server

    socket.ConnectionOptions = gowebsocket.ConnectionOptions {
       Proxy: gowebsocket.BuildProxy("http://example.com"),
    }

Setting data compression, ssl verification and subprotocols

• It can be set using connectionOptions inside socket

    socket.ConnectionOptions = gowebsocket.ConnectionOptions {
        UseSSL:true,
        UseCompression:true,
        Subprotocols: [] string{"chat","superchat"},
    }

• ConnectionOptions needs to be applied before connecting to server
• Please checkout examples/gowebsocket directory for detailed code..

License

Apache License, Version 2.0

gowebsocket's Issues

Runtime Error: Invalid memory address or nil pointer dereference

Hey Guys,

just bumped into this websocket topic and tried out this pkg for connecting to an open API. Maybe I am doing something wrong

Go Version: go1.13.5 darwin/amd64 (at Mac)

My Code:

func (api BrokerAPI) setupUpdateStream() {
	type authData struct {
		KeyID     string `json:"key_id"`
		SecretKey string `json:"secret_key"`
	}
	type streamAuthAction struct {
		Action string      `json:"action"`
		Data   interface{} `json:"data"`
	}

	streamURL := fmt.Sprintf("ws://%s/%s/%s", api.URL, apiVersion, streamEndpoint)

	socket := gowebsocket.New(streamURL)
	socket.Connect()

	streamAuthData := streamAuthAction{Action: "authenticate", Data: authData{KeyID: api.Key, SecretKey: api.Secret}}
	parsedAuthData, authErr := json.Marshal(streamAuthData)
	if authErr != nil {
		log.Fatalf("Authentication failed, because stream messages: %s", authErr)
	}

	socket.SendBinary(parsedAuthData)

	...
}

Connection Issue

I was trying your library and also have found that line 83 throw an exception because "resp" is nil when the websocket server is not available.

When i have commented that line, i could keep trying to connect to a wesocket server.

Disconnect handler is never called

From what I've been able to gather, the disconnect handler is never getting called, and I'm assuming because there's no actual reconnecting support, the connection will basically end up in a "bad state", where it thinks it's still connected.

Thread safe?

Is gowebsocket.Socket thread safe? Can I do something like this?

func foo(socket gowebsocket.Socket){
  log.Println("Connected to server");
  socket.SendText("Hi there, this is my sample test message")
}

...

socket.OnConnected = func(socket gowebsocket.Socket) {
  go foo(socket)
}

This is just an example.

Does this work with gin gonic?

Implement Reconnection, Ping interval, compression level for data

Implement reconnection using exponential backoff and plain reconnection timout.
Implement Pinging to server and ping timeout for detecting connection issues.
Implement compression level data setting.