mirror of
https://github.com/42wim/matterbridge.git
synced 2024-12-19 17:42:35 +01:00
194 lines
4.2 KiB
Go
194 lines
4.2 KiB
Go
// Copyright 2013 The Gorilla WebSocket 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 main
|
|
|
|
import (
|
|
"flag"
|
|
"html/template"
|
|
"io/ioutil"
|
|
"log"
|
|
"net/http"
|
|
"os"
|
|
"strconv"
|
|
"time"
|
|
|
|
"github.com/gorilla/websocket"
|
|
)
|
|
|
|
const (
|
|
// Time allowed to write the file to the client.
|
|
writeWait = 10 * time.Second
|
|
|
|
// Time allowed to read the next pong message from the client.
|
|
pongWait = 60 * time.Second
|
|
|
|
// Send pings to client with this period. Must be less than pongWait.
|
|
pingPeriod = (pongWait * 9) / 10
|
|
|
|
// Poll file for changes with this period.
|
|
filePeriod = 10 * time.Second
|
|
)
|
|
|
|
var (
|
|
addr = flag.String("addr", ":8080", "http service address")
|
|
homeTempl = template.Must(template.New("").Parse(homeHTML))
|
|
filename string
|
|
upgrader = websocket.Upgrader{
|
|
ReadBufferSize: 1024,
|
|
WriteBufferSize: 1024,
|
|
}
|
|
)
|
|
|
|
func readFileIfModified(lastMod time.Time) ([]byte, time.Time, error) {
|
|
fi, err := os.Stat(filename)
|
|
if err != nil {
|
|
return nil, lastMod, err
|
|
}
|
|
if !fi.ModTime().After(lastMod) {
|
|
return nil, lastMod, nil
|
|
}
|
|
p, err := ioutil.ReadFile(filename)
|
|
if err != nil {
|
|
return nil, fi.ModTime(), err
|
|
}
|
|
return p, fi.ModTime(), nil
|
|
}
|
|
|
|
func reader(ws *websocket.Conn) {
|
|
defer ws.Close()
|
|
ws.SetReadLimit(512)
|
|
ws.SetReadDeadline(time.Now().Add(pongWait))
|
|
ws.SetPongHandler(func(string) error { ws.SetReadDeadline(time.Now().Add(pongWait)); return nil })
|
|
for {
|
|
_, _, err := ws.ReadMessage()
|
|
if err != nil {
|
|
break
|
|
}
|
|
}
|
|
}
|
|
|
|
func writer(ws *websocket.Conn, lastMod time.Time) {
|
|
lastError := ""
|
|
pingTicker := time.NewTicker(pingPeriod)
|
|
fileTicker := time.NewTicker(filePeriod)
|
|
defer func() {
|
|
pingTicker.Stop()
|
|
fileTicker.Stop()
|
|
ws.Close()
|
|
}()
|
|
for {
|
|
select {
|
|
case <-fileTicker.C:
|
|
var p []byte
|
|
var err error
|
|
|
|
p, lastMod, err = readFileIfModified(lastMod)
|
|
|
|
if err != nil {
|
|
if s := err.Error(); s != lastError {
|
|
lastError = s
|
|
p = []byte(lastError)
|
|
}
|
|
} else {
|
|
lastError = ""
|
|
}
|
|
|
|
if p != nil {
|
|
ws.SetWriteDeadline(time.Now().Add(writeWait))
|
|
if err := ws.WriteMessage(websocket.TextMessage, p); err != nil {
|
|
return
|
|
}
|
|
}
|
|
case <-pingTicker.C:
|
|
ws.SetWriteDeadline(time.Now().Add(writeWait))
|
|
if err := ws.WriteMessage(websocket.PingMessage, []byte{}); err != nil {
|
|
return
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
func serveWs(w http.ResponseWriter, r *http.Request) {
|
|
ws, err := upgrader.Upgrade(w, r, nil)
|
|
if err != nil {
|
|
if _, ok := err.(websocket.HandshakeError); !ok {
|
|
log.Println(err)
|
|
}
|
|
return
|
|
}
|
|
|
|
var lastMod time.Time
|
|
if n, err := strconv.ParseInt(r.FormValue("lastMod"), 16, 64); err == nil {
|
|
lastMod = time.Unix(0, n)
|
|
}
|
|
|
|
go writer(ws, lastMod)
|
|
reader(ws)
|
|
}
|
|
|
|
func serveHome(w http.ResponseWriter, r *http.Request) {
|
|
if r.URL.Path != "/" {
|
|
http.Error(w, "Not found", 404)
|
|
return
|
|
}
|
|
if r.Method != "GET" {
|
|
http.Error(w, "Method not allowed", 405)
|
|
return
|
|
}
|
|
w.Header().Set("Content-Type", "text/html; charset=utf-8")
|
|
p, lastMod, err := readFileIfModified(time.Time{})
|
|
if err != nil {
|
|
p = []byte(err.Error())
|
|
lastMod = time.Unix(0, 0)
|
|
}
|
|
var v = struct {
|
|
Host string
|
|
Data string
|
|
LastMod string
|
|
}{
|
|
r.Host,
|
|
string(p),
|
|
strconv.FormatInt(lastMod.UnixNano(), 16),
|
|
}
|
|
homeTempl.Execute(w, &v)
|
|
}
|
|
|
|
func main() {
|
|
flag.Parse()
|
|
if flag.NArg() != 1 {
|
|
log.Fatal("filename not specified")
|
|
}
|
|
filename = flag.Args()[0]
|
|
http.HandleFunc("/", serveHome)
|
|
http.HandleFunc("/ws", serveWs)
|
|
if err := http.ListenAndServe(*addr, nil); err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
}
|
|
|
|
const homeHTML = `<!DOCTYPE html>
|
|
<html lang="en">
|
|
<head>
|
|
<title>WebSocket Example</title>
|
|
</head>
|
|
<body>
|
|
<pre id="fileData">{{.Data}}</pre>
|
|
<script type="text/javascript">
|
|
(function() {
|
|
var data = document.getElementById("fileData");
|
|
var conn = new WebSocket("ws://{{.Host}}/ws?lastMod={{.LastMod}}");
|
|
conn.onclose = function(evt) {
|
|
data.textContent = 'Connection closed';
|
|
}
|
|
conn.onmessage = function(evt) {
|
|
console.log('file updated');
|
|
data.textContent = evt.data;
|
|
}
|
|
})();
|
|
</script>
|
|
</body>
|
|
</html>
|
|
`
|