Custom WebSocket implementation library

Motivation

The main purpose of this developed package is education. I hold the rule which means if you want to figure out or understand something, you should to try to implement it. In the process of implementation I kept to this article and RFC 6455.

Description

This package is a custom WebSocket implementation library. It includes set of types, functions and methods using which you can easily create both client-side and server-side applications which can communicate on the WebSocket protocol.

Features that have already been done:

• ✅ Framing
• ✅ Pings/Pongs
• ✅ Reserved Bits
• ✅ Opcodes
• ✅ Fragmentation
• ✅ UTF-8 Handling
• ✅ Limits/Performance
• ✅ Opening and Closing Handshake

What's not done:

• ❌ Compression

Testing

For testing package I used Autobahn library. If you want to look at the Autobahn's report you should clone this repository and run test suites (make test) being in the folder with the project.

Installation

$ go get github.com/Mort4lis/websocket

How to use

Simple server

package main

import (
	"log"
	"net/http"

	"github.com/Mort4lis/websocket"
)

func handler(w http.ResponseWriter, req *http.Request) {
	conn, err := websocket.Upgrade(w, req)
	if err != nil {
		return
	}

	defer func() {
		_ = conn.Close()
	}()

	for {
		typ, payload, err := conn.ReadMessage()
		if err != nil {
			log.Println(err)
			return
		}

		if err = conn.WriteMessage(typ, payload); err != nil {
			log.Println(err)
			return
		}
	}
}

Simple client

package main

import (
	"log"
	"time"

	"github.com/Mort4lis/websocket"
)

func main() {
	dialer := &websocket.Dialer{
		HandshakeTimeout: 10 * time.Second,
	}

	conn, err := dialer.Dial("ws://127.0.0.1:8080")
	if err != nil {
		log.Fatal(err)
	}
	defer func() {
		_ = conn.Close()
	}()

	typ, payload, err := conn.ReadMessage()
	if err != nil {
		log.Fatal(err)
	}
	
	if err = conn.WriteMessage(typ, payload); err != nil {
		log.Fatal(err)
	}
}

For more detailed information please visit documentation.