I am using a websocket server coded in Python 3.5. This is needed to provide my website realtime information.
The "server"-library I use is called tornado (version 4.5b2) which handles the websocket connection and http requests. For backwards compatibility (if a browser does not support websocket yet) I use the python library sockjs-tornado (version 1.0.3) which also adds some additional features to the websocket connection.
Now my problem is that I get a lot of tornado ssl errors in the console if I start the server. It does not crash, but if about 80 clients are connected to the websocket 3 errors occur quite often. I use an encrypted connection and it works, but some clients are kicked out of the websocket connection if one of theese errors occur.
The Python script uses multiple threads and the server is protected by cloudflare, which is some kind of middleman and redirects every request to the server or user.
These are the 3 errors:
ERROR:tornado.general:Uncaught exception, closing connection.
Traceback (most recent call last):
File "/home/website/python/tornado/iostream.py", line 523, in _handle_events
self._handle_write()
File "/home/website/python/tornado/iostream.py", line 1398, in _handle_write
super(SSLIOStream, self)._handle_write()
File "/home/website/python/tornado/iostream.py", line 847, in _handle_write
assert self._write_buffer_size >= 0
AssertionError
ERROR:tornado.application:Exception in callback None
Traceback (most recent call last):
File "/home/website/python/tornado/ioloop.py", line 888, in start
handler_func(fd_obj, events)
File "/home/website/python/tornado/stack_context.py", line 277, in null_wrapper
return fn(*args, **kwargs)
File "/home/website/python/tornado/iostream.py", line 523, in _handle_events
self._handle_write()
File "/home/website/python/tornado/iostream.py", line 1398, in _handle_write
super(SSLIOStream, self)._handle_write()
File "/home/website/python/tornado/iostream.py", line 847, in _handle_write
assert self._write_buffer_size >= 0
AssertionError
This error does not appear as often as the first one.
ERROR:tornado.application:Uncaught exception GET /sockjs/398/ssputw1s/websocket
HTTPServerRequest(protocol='https', host='****.com:8443', method='GET', uri='/sockjs/398/ssputw1s/websocket', version='HTTP/1.1', remote_ip='****', headers={'Accept-Encoding': 'gzip', 'Cf-Visitor': '{"scheme":"https"}', 'Sec-Websocket-Key': '****', 'Host': '****.com:8443', 'X-Forwarded-Proto': 'https', 'Cache-Control': 'no-cache', 'Sec-Websocket-Version': '13', 'Cf-Ipcountry': 'FR', 'X-Forwarded-For': '****', 'Sec-Websocket-Extensions': 'x-webkit-deflate-frame', 'Origin': 'https://****.com', 'Cf-Connecting-Ip': '****', 'Cookie': '****', 'Upgrade': 'websocket', 'Cf-Ray': '34edb1a17c456908-CDG', 'User-Agent': '****', 'Connection': 'Upgrade', 'Pragma': 'no-cache'})
Traceback (most recent call last):
File "/home/website/python/tornado/web.py", line 1464, in _stack_context_handle_exception
raise_exc_info((type, value, traceback))
File "<string>", line 4, in raise_exc_info
File "/home/website/python/tornado/stack_context.py", line 316, in wrapped
ret = fn(*args, **kwargs)
File "/home/website/python/tornado/websocket.py", line 865, in _on_masked_frame_data
self._on_frame_data(_websocket_mask(self._frame_mask, data))
File "/home/website/python/tornado/websocket.py", line 910, in _on_frame_data
self._receive_frame()
File "/home/website/python/tornado/websocket.py", line 784, in _receive_frame
self.stream.read_bytes(2, self._on_frame_start)
File "/home/website/python/tornado/iostream.py", line 324, in read_bytes
self._try_inline_read()
File "/home/website/python/tornado/iostream.py", line 711, in _try_inline_read
pos = self._read_to_buffer_loop()
File "/home/website/python/tornado/iostream.py", line 625, in _read_to_buffer_loop
if self._read_to_buffer() == 0:
File "/home/website/python/tornado/iostream.py", line 738, in _read_to_buffer
chunk = self.read_from_fd()
File "/home/website/python/tornado/iostream.py", line 1487, in read_from_fd
chunk = self.socket.read(self.read_chunk_size)
File "/usr/lib64/python3.5/ssl.py", line 799, in read
return self._sslobj.read(len, buffer)
File "/usr/lib64/python3.5/ssl.py", line 585, in read
v = self._sslobj.read(len)
ssl.SSLWantWriteError: The operation did not complete (write) (_ssl.c:2090)
And sometimes this error appears:
ERROR:tornado.general:Uncaught exception, closing connection.
Traceback (most recent call last):
File "/home/website/python/tornado/iostream.py", line 523, in _handle_events
self._handle_write()
File "/home/website/python/tornado/iostream.py", line 1398, in _handle_write
super(SSLIOStream, self)._handle_write()
File "/home/website/python/tornado/iostream.py", line 872, in _handle_write
del self._write_buffer[:self._write_buffer_pos]
BufferError: Existing exports of data: object cannot be re-sized
ERROR:tornado.application:Exception in callback None
Traceback (most recent call last):
File "/home/website/python/tornado/ioloop.py", line 888, in start
handler_func(fd_obj, events)
File "/home/website/python/tornado/stack_context.py", line 277, in null_wrapper
return fn(*args, **kwargs)
File "/home/website/python/tornado/iostream.py", line 523, in _handle_events
self._handle_write()
File "/home/website/python/tornado/iostream.py", line 1398, in _handle_write
super(SSLIOStream, self)._handle_write()
File "/home/website/python/tornado/iostream.py", line 872, in _handle_write
del self._write_buffer[:self._write_buffer_pos]
BufferError: Existing exports of data: object cannot be re-sized
