WebSocket

使用 net 库的 WebSocket

服务端

server.go

  1. package main
  3. import (
  4.     "fmt"
  5.     "log"
  7.     "github.com/labstack/echo"
  8.     "github.com/labstack/echo/middleware"
  9.     "golang.org/x/net/websocket"
  10. )
  12. func hello(c echo.Context) error {
  13.     websocket.Handler(func(ws *websocket.Conn) {
  14.         defer ws.Close()
  15.         for {
  16.             // Write
  17.             err := websocket.Message.Send(ws, "Hello, Client!")
  18.             if err != nil {
  19.                 log.Fatal(err)
  20.             }
  22.             // Read
  23.             msg := ""
  24.             err = websocket.Message.Receive(ws, &msg)
  25.             if err != nil {
  26.                 log.Fatal(err)
  27.             }
  28.             fmt.Printf("%s\n", msg)
  29.         }
  30.     }).ServeHTTP(c.Response(), c.Request())
  31.     return nil
  32. }
  34. func main() {
  35.     e := echo.New()
  36.     e.Use(middleware.Logger())
  37.     e.Use(middleware.Recover())
  38.     e.Static("/", "../public")
  39.     e.GET("/ws", hello)
  40.     e.Logger.Fatal(e.Start(":1323"))
  41. }

使用 gorilla 的 WebSocket

服务端

server.go

  1. package main
  3. import (
  4.     "fmt"
  5.     "log"
  7.     "github.com/labstack/echo"
  9.     "github.com/gorilla/websocket"
  10.     "github.com/labstack/echo/middleware"
  11. )
  13. var (
  14.     upgrader = websocket.Upgrader{}
  15. )
  17. func hello(c echo.Context) error {
  18.     ws, err := upgrader.Upgrade(c.Response(), c.Request(), nil)
  19.     if err != nil {
  20.         return err
  21.     }
  22.     defer ws.Close()
  24.     for {
  25.         // Write
  26.         err := ws.WriteMessage(websocket.TextMessage, []byte("Hello, Client!"))
  27.         if err != nil {
  28.             log.Fatal(err)
  29.         }
  31.         // Read
  32.         _, msg, err := ws.ReadMessage()
  33.         if err != nil {
  34.             log.Fatal(err)
  35.         }
  36.         fmt.Printf("%s\n", msg)
  37.     }
  38. }
  40. func main() {
  41.     e := echo.New()
  42.     e.Use(middleware.Logger())
  43.     e.Use(middleware.Recover())
  44.     e.Static("/", "../public")
  45.     e.GET("/ws", hello)
  46.     e.Logger.Fatal(e.Start(":1323"))
  47. }

客户端

index.html

  1. <!doctype html>
  2. <html lang="en">
  4. <head>
  5.   <meta charset="utf-8">
  6.   <title>WebSocket</title>
  7. </head>
  9. <body>
  10.   <p id="output"></p>
  12.   <script>
  13.     var loc = window.location;
  14.     var uri = 'ws:';
  16.     if (loc.protocol === 'https:') {
  17.       uri = 'wss:';
  18.     }
  19.     uri += '//' + loc.host;
  20.     uri += loc.pathname + 'ws';
  22.     ws = new WebSocket(uri)
  24.     ws.onopen = function() {
  25.       console.log('Connected')
  26.     }
  28.     ws.onmessage = function(evt) {
  29.       var out = document.getElementById('output');
  30.       out.innerHTML += evt.data + '<br>';
  31.     }
  33.     setInterval(function() {
  34.       ws.send('Hello, Server!');
  35.     }, 1000);
  36.   </script>
  37. </body>
  39. </html>

输出示例

Client

  1. Hello, Client!
  2. Hello, Client!
  3. Hello, Client!
  4. Hello, Client!
  5. Hello, Client!

Server

  1. Hello, Server!
  2. Hello, Server!
  3. Hello, Server!
  4. Hello, Server!
  5. Hello, Server!