melody

:notes: Minimalist websocket framework for Go

Description

Melody is websocket framework based on github.com/gorilla/websocket that abstracts away the tedious parts of handling websockets. It gets out of your way so you can write real-time apps. Features include:

Programming language: Go

License: BSD 2-clause "Simplified" License

Tags: Web Frameworks     Websocket    

Latest version: v1.1.0

README

melody

:notes: Minimalist websocket framework for Go.

Melody is websocket framework based on github.com/gorilla/websocket that abstracts away the tedious parts of handling websockets. It gets out of your way so you can write real-time apps. Features include:

• [x] Clear and easy interface similar to net/http or Gin.
• [x] A simple way to broadcast to all or selected connected sessions.
• [x] Message buffers making concurrent writing safe.
• [x] Automatic handling of sending ping/pong heartbeats that timeout broken sessions.
• [x] Store data on sessions.

Install

go get github.com/olahol/melody

Example: chat

package main

import (
    "net/http"

    "github.com/olahol/melody"
)

func main() {
    m := melody.New()

    http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
        http.ServeFile(w, r, "index.html")
    })

    http.HandleFunc("/ws", func(w http.ResponseWriter, r *http.Request) {
        m.HandleRequest(w, r)
    })

    m.HandleMessage(func(s *melody.Session, msg []byte) {
        m.Broadcast(msg)
    })

    http.ListenAndServe(":5000", nil)
}

Example: gophers

package main

import (
    "net/http"
    "strings"

    "github.com/google/uuid"
    "github.com/olahol/melody"
)

type GopherInfo struct {
    ID, X, Y string
}

func main() {
    m := melody.New()

    http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
        http.ServeFile(w, r, "index.html")
    })

    http.HandleFunc("/ws", func(w http.ResponseWriter, r *http.Request) {
        m.HandleRequest(w, r)
    })

    m.HandleConnect(func(s *melody.Session) {
        ss, _ := m.Sessions()

        for _, o := range ss {
            value, exists := o.Get("info")

            if !exists {
                continue
            }

            info := value.(*GopherInfo)

            s.Write([]byte("set " + info.ID + " " + info.X + " " + info.Y))
        }

        id := uuid.NewString()
        s.Set("info", &GopherInfo{id, "0", "0"})

        s.Write([]byte("iam " + id))
    })

    m.HandleDisconnect(func(s *melody.Session) {
        value, exists := s.Get("info")

        if !exists {
            return
        }

        info := value.(*GopherInfo)

        m.BroadcastOthers([]byte("dis "+info.ID), s)
    })

    m.HandleMessage(func(s *melody.Session, msg []byte) {
        p := strings.Split(string(msg), " ")
        value, exists := s.Get("info")

        if len(p) != 2 || !exists {
            return
        }

        info := value.(*GopherInfo)
        info.X = p[0]
        info.Y = p[1]

        m.BroadcastOthers([]byte("set "+info.ID+" "+info.X+" "+info.Y), s)
    })

    http.ListenAndServe(":5000", nil)
}

More examples

Documentation

Contributors

FAQ

If you are getting a 403 when trying to connect to your websocket you can change allow all origin hosts:

m := melody.New()
m.Upgrader.CheckOrigin = func(r *http.Request) bool { return true }