simple-websocket-echo-server.go

package main

import (
	"log"
	"net/http"

	"github.com/gorilla/websocket"
)

var upgrader = websocket.Upgrader{} // use default options

func echo(w http.ResponseWriter, r *http.Request) {
	conn, err := upgrader.Upgrade(w, r, nil)
	if err != nil {
		log.Println("upgrade:", err)
		return
	}
	for {
		messageType, message, err := conn.ReadMessage()
		if err != nil {
			log.Println("read:", err)
			break
		}
		log.Println("recv:", string(message))
		err = conn.WriteMessage(messageType, message)
		if err != nil {
			log.Println("write:", err)
			break
		}
	}
}

func main() {
	log.SetFlags(log.LstdFlags | log.Lmicroseconds | log.Llongfile)

	http.HandleFunc("/echo", echo)
	http.Handle("/static/", http.StripPrefix("/static/", http.FileServer(http.Dir("./static/"))))

	log.Fatalln("fatal:", http.ListenAndServe("0.0.0.0:8080", nil))
}