add chat example

example/chat/controllers/default.go

@@ -0,0 +1,14 @@
+package controllers
+
+import (
+	"github.com/astaxie/beego"
+)
+
+type MainController struct {
+	beego.Controller
+}
+
+func (this *MainController) Get() {
+	this.Data["host"] = this.Ctx.Request.Host
+	this.TplNames = "index.tpl"
+}

example/chat/controllers/ws.go

@@ -0,0 +1,169 @@
+package controllers
+
+import (
+	"github.com/astaxie/beego"
+	"github.com/garyburd/go-websocket/websocket"
+	"io/ioutil"
+	"math/rand"
+	"net/http"
+	"time"
+)
+
+const (
+	// Time allowed to write a message to the client.
+	writeWait = 10 * time.Second
+
+	// Time allowed to read the next message from the client.
+	readWait = 60 * time.Second
+
+	// Send pings to client with this period. Must be less than readWait.
+	pingPeriod = (readWait * 9) / 10
+
+	// Maximum message size allowed from client.
+	maxMessageSize = 512
+)
+
+func init() {
+	rand.Seed(time.Now().UTC().UnixNano())
+	go h.run()
+}
+
+// connection is an middleman between the websocket connection and the hub.
+type connection struct {
+	username string
+
+	// The websocket connection.
+	ws *websocket.Conn
+
+	// Buffered channel of outbound messages.
+	send chan []byte
+}
+
+// readPump pumps messages from the websocket connection to the hub.
+func (c *connection) readPump() {
+	defer func() {
+		h.unregister <- c
+		c.ws.Close()
+	}()
+	c.ws.SetReadLimit(maxMessageSize)
+	c.ws.SetReadDeadline(time.Now().Add(readWait))
+	for {
+		op, r, err := c.ws.NextReader()
+		if err != nil {
+			break
+		}
+		switch op {
+		case websocket.OpPong:
+			c.ws.SetReadDeadline(time.Now().Add(readWait))
+		case websocket.OpText:
+			message, err := ioutil.ReadAll(r)
+			if err != nil {
+				break
+			}
+			h.broadcast <- []byte(c.username + "_" + time.Now().Format("15:04:05") + ":" + string(message))
+		}
+	}
+}
+
+// write writes a message with the given opCode and payload.
+func (c *connection) write(opCode int, payload []byte) error {
+	c.ws.SetWriteDeadline(time.Now().Add(writeWait))
+	return c.ws.WriteMessage(opCode, payload)
+}
+
+// writePump pumps messages from the hub to the websocket connection.
+func (c *connection) writePump() {
+	ticker := time.NewTicker(pingPeriod)
+	defer func() {
+		ticker.Stop()
+		c.ws.Close()
+	}()
+	for {
+		select {
+		case message, ok := <-c.send:
+			if !ok {
+				c.write(websocket.OpClose, []byte{})
+				return
+			}
+			if err := c.write(websocket.OpText, message); err != nil {
+				return
+			}
+		case <-ticker.C:
+			if err := c.write(websocket.OpPing, []byte{}); err != nil {
+				return
+			}
+		}
+	}
+}
+
+type hub struct {
+	// Registered connections.
+	connections map[*connection]bool
+
+	// Inbound messages from the connections.
+	broadcast chan []byte
+
+	// Register requests from the connections.
+	register chan *connection
+
+	// Unregister requests from connections.
+	unregister chan *connection
+}
+
+var h = &hub{
+	broadcast:   make(chan []byte, maxMessageSize),
+	register:    make(chan *connection, 1),
+	unregister:  make(chan *connection, 1),
+	connections: make(map[*connection]bool),
+}
+
+func (h *hub) run() {
+	for {
+		select {
+		case c := <-h.register:
+			h.connections[c] = true
+		case c := <-h.unregister:
+			delete(h.connections, c)
+			close(c.send)
+		case m := <-h.broadcast:
+			for c := range h.connections {
+				select {
+				case c.send <- m:
+				default:
+					close(c.send)
+					delete(h.connections, c)
+				}
+			}
+		}
+	}
+}
+
+type WSController struct {
+	beego.Controller
+}
+
+func (this *WSController) Get() {
+	ws, err := websocket.Upgrade(this.Ctx.ResponseWriter, this.Ctx.Request.Header, nil, 1024, 1024)
+	if _, ok := err.(websocket.HandshakeError); ok {
+		http.Error(this.Ctx.ResponseWriter, "Not a websocket handshake", 400)
+		return
+	} else if err != nil {
+		return
+	}
+	c := &connection{send: make(chan []byte, 256), ws: ws, username: randomString(10)}
+	h.register <- c
+	go c.writePump()
+	c.readPump()
+}
+
+func randomString(l int) string {
+	bytes := make([]byte, l)
+	for i := 0; i < l; i++ {
+		bytes[i] = byte(randInt(65, 90))
+	}
+	return string(bytes)
+}
+
+func randInt(min int, max int) int {
+	return min + rand.Intn(max-min)
+}