podhmo · May 26, 2021 11:23
diff --git a/02ssedemo.py b/02ssedemo.py
 import os
 import sys
 from wsgiref.simple_server import make_server

 PORT = int(os.getenv("PORT") or "8080")


 def app(environ, start_response):
    path = environ["PATH_INFO"]
    if path == "/sse":
        yield from sse(environ, start_response)
    else:
        yield from index(environ, start_response)


 def index(environ, start_response):
    status = "200 OK"
    headers = [
        ("Content-type", "text/html; charset=utf-8"),
    ]
    start_response(status, headers)
    yield f"""
 <body>
  <script>
    // const evtSource = new EventSource("//localhost:{PORT}/sse", {{ withCredentials: true }} ); 
    const evtSource = new EventSource("//localhost:{PORT}/sse", {{ withCredentials: false }} ); 
    evtSource.onmessage = function(e) {{
      var newElement = document.createElement("li");
      var eventList = document.getElementById('list');

      newElement.innerHTML = "message: " + e.data;
      eventList.appendChild(newElement);
    }};

    evtSource.addEventListener("clock",  function(e){{
      var newElement = document.createElement("li");
      var eventList = document.getElementById('list');

      newElement.innerHTML = "clock: " + e.data;
      eventList.appendChild(newElement);
    }});

    // default events
    evtSource.addEventListener("open",  function(e){{
      console.log("open")
    }});
    evtSource.addEventListener('error', function(event) {{
        switch (event.target.readyState) {{
            case EventSource.CONNECTING:
                console.log('Reconnecting...');
                break;
            case EventSource.CLOSED:
                console.log('Connection failed, will not reconnect');
                break;
        }}
      }});

    // if evtSource.close() is not called, reset connection
  </script>
 <body>
  <div id="list"></div>
 </body>
 </body>
 """.encode(
        "utf-8"
    )


 def sse(environ, start_response):
    import time

    status = "200 OK"
    headers = [
        ("Content-type", "text/event-stream; charset=utf-8"),
        ("Cache-Control", "no-cache"),
    ]
    start_response(status, headers)
    yield ": this is a test stream".encode("utf-8")  # this is comment
    yield "\n".encode("utf-8")

    for i in range(10):

        yield "event: clock\n".encode("utf-8")
        yield f'data: {{"time": "{time.time()}", "c": {i} }}\n'.encode("utf-8")
        yield "\n".encode("utf-8")
        time.sleep(0.5)


 httpd = make_server("", PORT, app)
 print(f"Serving on port {PORT}...", file=sys.stderr)

 # Serve until process is killed
 httpd.serve_forever()
	import os
	import sys
	from wsgiref.simple_server import make_server

	PORT = int(os.getenv("PORT") or "8080")


	def app(environ, start_response):
	path = environ["PATH_INFO"]
	if path == "/sse":
	yield from sse(environ, start_response)
	else:
	yield from index(environ, start_response)


	def index(environ, start_response):
	status = "200 OK"
	headers = [
	("Content-type", "text/html; charset=utf-8"),
	]
	start_response(status, headers)
	yield f"""
	<body>
	<script>
	// const evtSource = new EventSource("//localhost:{PORT}/sse", {{ withCredentials: true }} );
	const evtSource = new EventSource("//localhost:{PORT}/sse", {{ withCredentials: false }} );
	evtSource.onmessage = function(e) {{
	var newElement = document.createElement("li");
	var eventList = document.getElementById('list');

	newElement.innerHTML = "message: " + e.data;
	eventList.appendChild(newElement);
	}};

	evtSource.addEventListener("clock", function(e){{
	var newElement = document.createElement("li");
	var eventList = document.getElementById('list');

	newElement.innerHTML = "clock: " + e.data;
	eventList.appendChild(newElement);
	}});

	// default events
	evtSource.addEventListener("open", function(e){{
	console.log("open")
	}});
	evtSource.addEventListener('error', function(event) {{
	switch (event.target.readyState) {{
	case EventSource.CONNECTING:
	console.log('Reconnecting...');
	break;
	case EventSource.CLOSED:
	console.log('Connection failed, will not reconnect');
	break;
	}}
	}});

	// if evtSource.close() is not called, reset connection
	</script>
	<body>
	<div id="list"></div>
	</body>
	</body>
	""".encode(
	"utf-8"
	)


	def sse(environ, start_response):
	import time

	status = "200 OK"
	headers = [
	("Content-type", "text/event-stream; charset=utf-8"),
	("Cache-Control", "no-cache"),
	]
	start_response(status, headers)
	yield ": this is a test stream".encode("utf-8") # this is comment
	yield "\n".encode("utf-8")

	for i in range(10):

	yield "event: clock\n".encode("utf-8")
	yield f'data: {{"time": "{time.time()}", "c": {i} }}\n'.encode("utf-8")
	yield "\n".encode("utf-8")
	time.sleep(0.5)


	httpd = make_server("", PORT, app)
	print(f"Serving on port {PORT}...", file=sys.stderr)

	# Serve until process is killed
	httpd.serve_forever()