9nut · February 26, 2025 17:31
diff --git a/wstest.go b/wstest.go
 package main

 import (
 	"flag"
 	"net/http"
 	"io"
 	"time"
 	"golang.org/x/net/websocket"
 	"log"
 )

 // Echo everything back.
 func EchoServer(ws *websocket.Conn) {
 	io.Copy(ws, ws)
 }

 // Send clock ticks.
 func TimeServer(ws *websocket.Conn) {
 	for {
 		if _, err := ws.Write([]byte(time.Now().String())); err != nil {
 			log.Println("Write: ", err)
 			return
 		}
 		time.Sleep(1e+9)
 	}
 }

 func greeter(w http.ResponseWriter, req *http.Request) {
 	w.Header().Set("Content-Type", "text/html")
 	w.Write([]byte(homepage))
 }

 func main() {
 	var port string
 	flag.StringVar(&port, "http", ":12345", "[-http xxxx] # default 12345")
 	flag.Parse()
 	http.HandleFunc("/",  greeter)
 	http.Handle("/src/", http.StripPrefix("/src/", http.FileServer(http.Dir("./"))))
 	http.Handle("/echo", websocket.Handler(EchoServer))
 	http.Handle("/time", websocket.Handler(TimeServer))
 	err := http.ListenAndServe(port, nil)
 	if err != nil {
 		log.Fatal("ListenAndServe: " + err.Error())
 	}
 }

 var homepage string = `
 <!DOCTYPE html>
 <meta charset="utf-8" />
 <title>Clock Server via WebSocket</title>
 <script language="JavaScript">
 wstest = (function () {
 	var hostport = window.location.host
 	var timeuri = "ws://"+hostport+"/time";
 	var echouri = "ws://"+hostport+"/echo";
 	var timesock;
 	var echosock;
 	var stats;
 	var clock;
 	var echoback;
 	function updatestat(msg, e) {
 		stats.innerHTML = '<span style="color: red;">'+msg+'</span> '+e.data;
 	}

 	function updateclock(e) {
 		clock.innerHTML = '<span style="color: blue;">'+e.data+'</span>';
 		echosock.send('<span style="color:green;">Sent by client: '+e.data+'</span>');
 	}

 	return	function () {
 		MakeSock = (typeof WebSocket !== "undefined")?WebSocket:MozWebSocket;
 		echosock = new MakeSock(echouri);
 		echoback = document.getElementById("echoback");
 		echosock.onmessage = function(e) { echoback.innerHTML=e.data };

 		timesock = new MakeSock(timeuri);
 		stats = document.getElementById("status");
 		clock = document.getElementById("clock");
 		timesock.onopen = function(e) { updatestat("Open:", e) };
 		timesock.onclose = function(e) { updatestat("Close:", e) };
 		timesock.onmessage = function(e) { updateclock(e) };
 		timesock.onerror = function(e) { updatestat("Error:", e) };
 	}
 })();

 window.addEventListener("load", wstest, false);
 </script>
 <h2>Time Reporting From Server</h2>
 <p id="status"></p>
 <p id="clock"></p>
 <p id="echoback"></p>
 </html>
 `
	package main

	import (
	"flag"
	"net/http"
	"io"
	"time"
	"golang.org/x/net/websocket"
	"log"
	)

	// Echo everything back.
	func EchoServer(ws *websocket.Conn) {
	io.Copy(ws, ws)
	}

	// Send clock ticks.
	func TimeServer(ws *websocket.Conn) {
	for {
	if _, err := ws.Write([]byte(time.Now().String())); err != nil {
	log.Println("Write: ", err)
	return
	}
	time.Sleep(1e+9)
	}
	}

	func greeter(w http.ResponseWriter, req *http.Request) {
	w.Header().Set("Content-Type", "text/html")
	w.Write([]byte(homepage))
	}

	func main() {
	var port string
	flag.StringVar(&port, "http", ":12345", "[-http xxxx] # default 12345")
	flag.Parse()
	http.HandleFunc("/", greeter)
	http.Handle("/src/", http.StripPrefix("/src/", http.FileServer(http.Dir("./"))))
	http.Handle("/echo", websocket.Handler(EchoServer))
	http.Handle("/time", websocket.Handler(TimeServer))
	err := http.ListenAndServe(port, nil)
	if err != nil {
	log.Fatal("ListenAndServe: " + err.Error())
	}
	}

	var homepage string = `
	<!DOCTYPE html>
	<meta charset="utf-8" />
	<title>Clock Server via WebSocket</title>
	<script language="JavaScript">
	wstest = (function () {
	var hostport = window.location.host
	var timeuri = "ws://"+hostport+"/time";
	var echouri = "ws://"+hostport+"/echo";
	var timesock;
	var echosock;
	var stats;
	var clock;
	var echoback;
	function updatestat(msg, e) {
	stats.innerHTML = '<span style="color: red;">'+msg+'</span> '+e.data;
	}

	function updateclock(e) {
	clock.innerHTML = '<span style="color: blue;">'+e.data+'</span>';
	echosock.send('<span style="color:green;">Sent by client: '+e.data+'</span>');
	}

	return function () {
	MakeSock = (typeof WebSocket !== "undefined")?WebSocket:MozWebSocket;
	echosock = new MakeSock(echouri);
	echoback = document.getElementById("echoback");
	echosock.onmessage = function(e) { echoback.innerHTML=e.data };

	timesock = new MakeSock(timeuri);
	stats = document.getElementById("status");
	clock = document.getElementById("clock");
	timesock.onopen = function(e) { updatestat("Open:", e) };
	timesock.onclose = function(e) { updatestat("Close:", e) };
	timesock.onmessage = function(e) { updateclock(e) };
	timesock.onerror = function(e) { updatestat("Error:", e) };
	}
	})();

	window.addEventListener("load", wstest, false);
	</script>
	<h2>Time Reporting From Server</h2>
	<p id="status"></p>
	<p id="clock"></p>
	<p id="echoback"></p>
	</html>
	`