pubsub.go

package main

import (
	"math/rand"
	"net/http"
	"sync"

	"golang.org/x/net/websocket"
)

type Deployd struct {
	pubsub map[int64]chan []byte
	lock   sync.Mutex
}

func (d *Deployd) bye(id int64) {
	defer d.lock.Unlock()
	d.lock.Lock()
	delete(d.pubsub, id)
}

// Echo the data received on the WebSocket.
func (d *Deployd) Sub(ws *websocket.Conn) {
	k := rand.Int63()
	c := make(chan []byte)
	d.pubsub[k] = c
	defer d.bye(k)
	for {
		ws.Write(<-c)
	}
}

func (d *Deployd) pub(msg []byte) {
	defer d.lock.Unlock()
	d.lock.Lock()
	for _, c := range d.pubsub {
		c <- msg
	}
}

func (d *Deployd) Pub(w http.ResponseWriter, req *http.Request) {
	msg := req.FormValue("msg")
	d.pub([]byte(msg))
	w.WriteHeader(201)
}

// This example demonstrates a trivial echo server.
func main() {
	d := Deployd{}
	d.pubsub = make(map[int64]chan []byte)
	http.HandleFunc("/pub", d.Pub)
	http.Handle("/sub", websocket.Handler(d.Sub))
	http.Handle("/", http.FileServer(http.Dir("static")))
	//http.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
	//http.ServeFile(w, req, "static/index.html")
	//})
	err := http.ListenAndServe(":12345", nil)
	if err != nil {
		panic("ListenAndServe: " + err.Error())
	}
}