Exception logged in Windows from select() due to Rejected event

[gmyers18]

The following trivial script results in a log.exception() message in Windows, which doesn't seem like the expected behavior.

import lomond

ws = lomond.WebSocket('ws://www.google.com')
events = list(ws.connect())
print(events)

Output:

[Connecting(url='ws://www.google.com'), Connected(url='ws://www.google.com'), Rejected(<response HTTP/1.1 400 Bad Request>, 'Websocket upgrade failed (code=400)'), Disconnected('error; file descriptor cannot be a negative integer (-1)', graceful=False)]
error in websocket loop
Traceback (most recent call last):
  File "C:\Projects\venv\websocket_client_playground\lib\site-packages\lomond\session.py", line 384, in run
    readable = selector.wait_readable(poll)
  File "C:\Projects\venv\websocket_client_playground\lib\site-packages\lomond\selectors.py", line 32, in wait_readable
    select.select([self._socket.fileno()], [], [], timeout)
ValueError: file descriptor cannot be a negative integer (-1)

Environment:

• Python 3.5.3
• lomond 0.2.1
• Windows 10 Pro 1709 16299.309

When a HandshakeError is encountered in WebSocket.feed(), leading to a Rejected event, the socket is ultimately closed. The issue is with the call to select() in SelectSelector.wait_readable() which happens after this, as self._socket.fileno() will return -1.

A trivial solution is to wrap the code in wait_readable() in a blanket try/except and return True in the failure case. This will allow normal processing to proceed in WebsocketSession.run() and the session will close out gracefully.

[willmcgugan]

Fixed in 0.2.2