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// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package websocket
import (
"bufio"
"fmt"
"io"
"net/http"
)
func newServerConn(rwc io.ReadWriteCloser, buf *bufio.ReadWriter, req *http.Request) (conn *Conn, err error) {
config := new(Config)
var hs serverHandshaker = &hybiServerHandshaker{Config: config}
code, err := hs.ReadHandshake(buf.Reader, req)
if err == ErrBadWebSocketVersion {
fmt.Fprintf(buf, "HTTP/1.1 %03d %s\r\n", code, http.StatusText(code))
fmt.Fprintf(buf, "Sec-WebSocket-Version: %s\r\n", SupportedProtocolVersion)
buf.WriteString("\r\n")
buf.WriteString(err.Error())
buf.Flush()
return
}
if err != nil {
hs = &hixie76ServerHandshaker{Config: config}
code, err = hs.ReadHandshake(buf.Reader, req)
}
if err != nil {
hs = &hixie75ServerHandshaker{Config: config}
code, err = hs.ReadHandshake(buf.Reader, req)
}
if err != nil {
fmt.Fprintf(buf, "HTTP/1.1 %03d %s\r\n", code, http.StatusText(code))
buf.WriteString("\r\n")
buf.WriteString(err.Error())
buf.Flush()
return
}
config.Protocol = nil
err = hs.AcceptHandshake(buf.Writer)
if err != nil {
code = http.StatusBadRequest
fmt.Fprintf(buf, "HTTP/1.1 %03d %s\r\n", code, http.StatusText(code))
buf.WriteString("\r\n")
buf.Flush()
return
}
conn = hs.NewServerConn(buf, rwc, req)
return
}
/*
Handler is an interface to a WebSocket.
A trivial example server:
package main
import (
"http"
"io"
"websocket"
)
// Echo the data received on the WebSocket.
func EchoServer(ws *websocket.Conn) {
io.Copy(ws, ws);
}
func main() {
http.Handle("/echo", websocket.Handler(EchoServer));
err := http.ListenAndServe(":12345", nil);
if err != nil {
panic("ListenAndServe: " + err.String())
}
}
*/
type Handler func(*Conn)
// ServeHTTP implements the http.Handler interface for a Web Socket
func (h Handler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
rwc, buf, err := w.(http.Hijacker).Hijack()
if err != nil {
panic("Hijack failed: " + err.Error())
return
}
// The server should abort the WebSocket connection if it finds
// the client did not send a handshake that matches with protocol
// specification.
defer rwc.Close()
conn, err := newServerConn(rwc, buf, req)
if err != nil {
return
}
if conn == nil {
panic("unepxected nil conn")
}
h(conn)
}
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