I work with websocket in go. And I got a websocket url format from a trivial example that I google like this:
ws://{{$}}/ws
Relatively complete code below:
home.html:
<html>
<head>
<title>Chat Example</title>
<script type="text/javascript">
$(function() {
......
if (window["WebSocket"]) {
conn = new WebSocket("ws://{{$}}/ws");
conn.onclose = function(evt) {
appendLog($("<div><b>Connection closed.</b></div>"))
}
conn.onmessage = function(evt) {
appendLog($("<div/>").text(evt.data))
}
} else {
appendLog($("<div><b>Your browser does not support WebSockets.</b></div>"))
}
......
});
</script>
</head>
</html>
And wsServer.go:
package main
import (
"flag"
"log"
"net/http"
"text/template"
)
var addr = flag.String("addr", ":8080", "http service address")
var homeTempl = template.Must(template.ParseFiles("home.html"))
func serveHome(w http.ResponseWriter, r *http.Request) {
......
w.Header().Set("Content-Type", "text/html; charset=utf-8")
homeTempl.Execute(w, r.Host)
}
func main() {
http.HandleFunc("/", serveHome)
http.HandleFunc("/ws", serveWs)
err := http.ListenAndServe(:8080, nil)
if err != nil {
log.Fatal("ListenAndServe: ", err)
}
}
I thought it would be a regular expression while actually I can't explain it.
I test it on my own PC browser, and connect success with:
http://localhost:8080
but
http://ip:8080 (which ip is my computer's also the litsening server's ip)
not. And why?
Of course it works when I change "ws://{{$}}/ws" to a certain url. But I want to know why?And what can this expression matching for?
The complete example code is large, I think above is enough to the question. If I miss something you can find out complete example in this page : https://github.com/garyburd/go-websocket/tree/master/examples/chat
