minrk · September 25, 2025 04:54
diff --git a/docker-compose.yaml b/docker-compose.yaml
 services:
  proxy:
    image: ghcr.io/minrk/configurable-http-proxy:custom-dump-netstat
    # build:
    #   context: ..
    command:
      - --error-target=http://error-target
      - --default-target=http://169.254.0.0
      - --log-level=debug
    environment:
      DEBUG: "*"
      NETSTAT_SECONDS: "10"
    ports:
      - 8000:8000
  
  error-target:
    build:
      context: error-target
  
diff --git a/Dockerfile b/Dockerfile
 FROM python:3.13-alpine
 RUN apk add --no-cache net-tools
 RUN pip install tornado
 COPY main.py /main.py
 CMD ["python3", "main.py"]
diff --git a/main.py b/main.py
 import asyncio
 import tornado

 class MainHandler(tornado.web.RequestHandler):
    def get(self, code):
        self.write(f"Code: {code}")


 async def main():
    application = tornado.web.Application([(r"/(.+)", MainHandler)])
    http_server = tornado.httpserver.HTTPServer(application)
    http_server.listen(80)
    await asyncio.Event().wait()


 if __name__ == "__main__":
    asyncio.run(main())
diff --git a/test.html b/test.html
 <html>
  <title>Websocket test</title>
 <body>
  <input type="checkbox" checked name="pause" id="pause">
  <label for="pause">Pause</label>
  <input type="checkbox" checked name="websocket" id="websocket">
  <label for="websocket">WebSocket</label>
  <ul id="output"></ul>
  <script type="text/javascript">
    
    // document.location.href;
    const htmlUrl = "http://127.0.1:8000/";
    const wsUrl = "ws" + htmlUrl.slice(4);
    const connectEveryMs = 100;

    function log(msg) {
      const ul = document.getElementById("output");
      const li = document.createElement("li");
      li.innerText = `${(new Date()).toLocaleTimeString()} ${msg}`;
      ul.insertBefore(li, ul.firstChild);
      // limit length
      if (ul.childElementCount > 10) {
        ul.removeChild(ul.lastChild);
      }
    }

    function connect() {
      if (document.getElementById("pause").checked) {
        setTimeout(connect, connectEveryMs);
        return;
      }
      if (document.getElementById("websocket").checked) {
        connectWs();
      } else {
        connectFetch();
      }
    };
    
    async function connectFetch() {
      log(`fetching ${htmlUrl}`)
      try {
        const r = await fetch(htmlUrl);
        log("fetched ok");
      } catch (e) {
        log(`fetch error ${e.toString()}`);
        console.error(e);
      }
      setTimeout(connect, connectEveryMs);
    }
    function connectWs() {
      log("connecting websocket");
      const ws = new WebSocket(wsUrl);
      // connect every this often
      // these are all going to fail,
      // but it appears that failed ws connections are causing port exhaustion errors
      ws.onerror = (err) => {
        log("error");
        console.error(err);
      };
      ws.onclose = () => {
        log("close");
        setTimeout(connect, connectEveryMs);
      }
    }
    connect();
  </script>
 </body>
 </html>
	services:
	proxy:
	image: ghcr.io/minrk/configurable-http-proxy:custom-dump-netstat
	# build:
	# context: ..
	command:
	- --error-target=http://error-target
	- --default-target=http://169.254.0.0
	- --log-level=debug
	environment:
	DEBUG: "*"
	NETSTAT_SECONDS: "10"
	ports:
	- 8000:8000

	error-target:
	build:
	context: error-target
	FROM python:3.13-alpine
	RUN apk add --no-cache net-tools
	RUN pip install tornado
	COPY main.py /main.py
	CMD ["python3", "main.py"]
	import asyncio
	import tornado

	class MainHandler(tornado.web.RequestHandler):
	def get(self, code):
	self.write(f"Code: {code}")


	async def main():
	application = tornado.web.Application([(r"/(.+)", MainHandler)])
	http_server = tornado.httpserver.HTTPServer(application)
	http_server.listen(80)
	await asyncio.Event().wait()


	if __name__ == "__main__":
	asyncio.run(main())
	<html>
	<title>Websocket test</title>
	<body>
	<input type="checkbox" checked name="pause" id="pause">
	<label for="pause">Pause</label>
	<input type="checkbox" checked name="websocket" id="websocket">
	<label for="websocket">WebSocket</label>
	<ul id="output"></ul>
	<script type="text/javascript">

	// document.location.href;
	const htmlUrl = "http://127.0.1:8000/";
	const wsUrl = "ws" + htmlUrl.slice(4);
	const connectEveryMs = 100;

	function log(msg) {
	const ul = document.getElementById("output");
	const li = document.createElement("li");
	li.innerText = `${(new Date()).toLocaleTimeString()} ${msg}`;
	ul.insertBefore(li, ul.firstChild);
	// limit length
	if (ul.childElementCount > 10) {
	ul.removeChild(ul.lastChild);
	}
	}

	function connect() {
	if (document.getElementById("pause").checked) {
	setTimeout(connect, connectEveryMs);
	return;
	}
	if (document.getElementById("websocket").checked) {
	connectWs();
	} else {
	connectFetch();
	}
	};

	async function connectFetch() {
	log(`fetching ${htmlUrl}`)
	try {
	const r = await fetch(htmlUrl);
	log("fetched ok");
	} catch (e) {
	log(`fetch error ${e.toString()}`);
	console.error(e);
	}
	setTimeout(connect, connectEveryMs);
	}
	function connectWs() {
	log("connecting websocket");
	const ws = new WebSocket(wsUrl);
	// connect every this often
	// these are all going to fail,
	// but it appears that failed ws connections are causing port exhaustion errors
	ws.onerror = (err) => {
	log("error");
	console.error(err);
	};
	ws.onclose = () => {
	log("close");
	setTimeout(connect, connectEveryMs);
	}
	}
	connect();
	</script>
	</body>
	</html>