反馈 参与翻译... 2019.6.16更新

WebSocket

使用 net 库的 WebSocket

服务端

server.go

package main

import (
	"fmt"
	"log"

	"github.com/labstack/echo"
	"github.com/labstack/echo/middleware"
	"golang.org/x/net/websocket"
)

func hello(c echo.Context) error {
	websocket.Handler(func(ws *websocket.Conn) {
		defer ws.Close()
		for {
			// Write
			err := websocket.Message.Send(ws, "Hello, Client!")
			if err != nil {
				log.Fatal(err)
			}

			// Read
			msg := ""
			err = websocket.Message.Receive(ws, &msg)
			if err != nil {
				log.Fatal(err)
			}
			fmt.Printf("%s\n", msg)
		}
	}).ServeHTTP(c.Response(), c.Request())
	return nil
}

func main() {
	e := echo.New()
	e.Use(middleware.Logger())
	e.Use(middleware.Recover())
	e.Static("/", "../public")
	e.GET("/ws", hello)
	e.Logger.Fatal(e.Start(":1323"))
}

使用 gorilla 的 WebSocket

服务端

server.go

package main

import (
	"fmt"
	"log"

	"github.com/labstack/echo"

	"github.com/gorilla/websocket"
	"github.com/labstack/echo/middleware"
)

var (
	upgrader = websocket.Upgrader{}
)

func hello(c echo.Context) error {
	ws, err := upgrader.Upgrade(c.Response(), c.Request(), nil)
	if err != nil {
		return err
	}
	defer ws.Close()

	for {
		// Write
		err := ws.WriteMessage(websocket.TextMessage, []byte("Hello, Client!"))
		if err != nil {
			log.Fatal(err)
		}

		// Read
		_, msg, err := ws.ReadMessage()
		if err != nil {
			log.Fatal(err)
		}
		fmt.Printf("%s\n", msg)
	}
}

func main() {
	e := echo.New()
	e.Use(middleware.Logger())
	e.Use(middleware.Recover())
	e.Static("/", "../public")
	e.GET("/ws", hello)
	e.Logger.Fatal(e.Start(":1323"))
}

客户端

index.html

<!doctype html>
<html lang="en">

<head>
  <meta charset="utf-8">
  <title>WebSocket</title>
</head>

<body>
  <p id="output"></p>

  <script>
    var loc = window.location;
    var uri = 'ws:';

    if (loc.protocol === 'https:') {
      uri = 'wss:';
    }
    uri += '//' + loc.host;
    uri += loc.pathname + 'ws';

    ws = new WebSocket(uri)

    ws.onopen = function() {
      console.log('Connected')
    }

    ws.onmessage = function(evt) {
      var out = document.getElementById('output');
      out.innerHTML += evt.data + '<br>';
    }

    setInterval(function() {
      ws.send('Hello, Server!');
    }, 1000);
  </script>
</body>

</html>

输出示例

Client

Hello, Client!
Hello, Client!
Hello, Client!
Hello, Client!
Hello, Client!

Server

Hello, Server!
Hello, Server!
Hello, Server!
Hello, Server!
Hello, Server!