/
conn.go
73 lines (67 loc) · 1.35 KB
/
conn.go
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package main
import (
"github.com/gorilla/websocket"
"log"
"net/http"
"time"
)
const (
maximumAllowedTime = 24 * time.Hour
maxMessageSize = 512
)
type Connection struct {
fromAddr string
ws *websocket.Conn
send chan []byte
}
func (c *Connection) readPump() {
defer func() {
h.unregister <- c
c.ws.Close()
}()
c.ws.SetReadLimit(maxMessageSize)
c.ws.SetReadDeadline(time.Now().Add(maximumAllowedTime))
for {
_, _, err := c.ws.ReadMessage()
if err != nil {
break
}
// we do not expect any input
}
}
func (c *Connection) writePump() {
defer func() {
c.ws.Close()
}()
for {
select {
case message, ok := <-c.send:
if !ok {
c.ws.WriteMessage(websocket.CloseMessage, []byte{})
return
}
if err := c.ws.WriteMessage(websocket.TextMessage, message); err != nil {
return
}
}
}
}
func serveWs(w http.ResponseWriter, r *http.Request) {
if r.Method != "GET" {
http.Error(w, "Method not allowed", 405)
return
}
// we do not check origin - it's a feature :-)
ws, err := websocket.Upgrade(w, r, nil, 1024, 1024)
if _, ok := err.(websocket.HandshakeError); ok {
http.Error(w, "Not a websocket handshake", 400)
return
} else if err != nil {
log.Println(err)
return
}
c := &Connection{send: make(chan []byte, 256), ws: ws, fromAddr: r.RemoteAddr}
h.register <- c
go c.writePump()
c.readPump()
}