# websocketd
# WebSocket 服务器
阮一峰 websocket (opens new window)
后台脚本不限语言，标准输入（stdin）就是 WebSocket 的输入，标准输出（stdout）就是 WebSocket 的输出。
# 示例
To get started, we'll create a WebSocket endpoint that will accept connections, then send back messages, counting to 10 with 1 second pause between each one, before disconnecting.
To show how simple it is, let's do it in Bash!
count.sh:
#!/bin/bash
for ((COUNT = 1; COUNT <= 10; COUNT++)); do
echo $COUNT
sleep 1
done
Before turning it into a WebSocket server, let's test it from the command line. The beauty of websocketd is that servers work equally well in the command line, or in shell scripts, as they do in the server - with no modifications required.
chmod +x count.sh
$ ./count.sh
1
2
3
4
5
6
7
8
9
10
Now let's turn it into a WebSocket server:
websocketd --port=8080 ./count.sh
Finally, let's create a web-page that to test it.
count.html:
<!DOCTYPE html>
<pre id="log"></pre>
<script>
// helper function: log message to screen
function log(msg) {
document.getElementById("log").textContent += msg + "\n";
}
// setup websocket with callbacks
var ws = new WebSocket("ws://localhost:8080/");
ws.onopen = function() {
log("CONNECT");
};
ws.onclose = function() {
log("DISCONNECT");
};
ws.onmessage = function(event) {
log("MESSAGE: " + event.data);
};
</script>
Open this page in your web-browser. It will even work if you open it directly
from disk using a file:// URL.