fix unawait asyncio coroutines; refactor decorator/yield from in favor of await/async

websocket-tcp-chat/client.py

@@ -1,5 +1,5 @@
 #!/usr/bin/env python3
-"""websocket cmd client for wssrv.py example."""
+"""websocket cmd client for actix/websocket-tcp-chat example."""
 import argparse
 import asyncio
 import signal
@@ -7,46 +7,54 @@ import sys
 
 import aiohttp
 
+queue = asyncio.Queue()
 
-def start_client(loop, url):
+
+async def start_client(url):
     name = input('Please enter your name: ')
 
-    # send request
-    ws = yield from aiohttp.ClientSession().ws_connect(url, autoclose=False, autoping=False)
+    ws = await aiohttp.ClientSession().ws_connect(url, autoclose=False, autoping=False)
 
-    # input reader
     def stdin_callback():
         line = sys.stdin.buffer.readline().decode('utf-8')
         if not line:
             loop.stop()
         else:
-            ws.send_str(name + ': ' + line)
-    loop.add_reader(sys.stdin.fileno(), stdin_callback)
+            # Queue.put is a coroutine, so you can't call it directly.
+            asyncio.ensure_future(queue.put(ws.send_str(name + ': ' + line)))
 
-    @asyncio.coroutine
-    def dispatch():
+    loop.add_reader(sys.stdin, stdin_callback)
+
+    async def dispatch():
         while True:
-            msg = yield from ws.receive()
-
+            msg = await ws.receive()
             if msg.type == aiohttp.WSMsgType.TEXT:
                 print('Text: ', msg.data.strip())
             elif msg.type == aiohttp.WSMsgType.BINARY:
                 print('Binary: ', msg.data)
             elif msg.type == aiohttp.WSMsgType.PING:
-                yield from ws.pong()
+                await ws.pong()
             elif msg.type == aiohttp.WSMsgType.PONG:
                 print('Pong received')
             else:
                 if msg.type == aiohttp.WSMsgType.CLOSE:
-                    yield from ws.close()
+                    await ws.close()
                 elif msg.type == aiohttp.WSMsgType.ERROR:
                     print('Error during receive %s' % ws.exception())
                 elif msg.type == aiohttp.WSMsgType.CLOSED:
                     pass
-
                 break
 
-    yield from dispatch()
+    await dispatch()
+
+
+async def tick():
+    while 1:
+        await (await queue.get())
+
+
+async def main(url):
+    await asyncio.wait([start_client(url), tick()])
 
 
 ARGS = argparse.ArgumentParser(
@@ -68,5 +76,5 @@ if __name__ == '__main__':
 
     loop = asyncio.get_event_loop()
     loop.add_signal_handler(signal.SIGINT, loop.stop)
-    asyncio.Task(start_client(loop, url))
+    asyncio.Task(main(url))
     loop.run_forever()