gunicorn and websockets

Question

I'm trying to get http://www.gelens.org/code/gevent-websocket/ running and keep getting the following error.

socket_id=1 already closed.
    result = self._run(*self.args, **self.kwargs)
  File "/home/walt/virtualenv/ws/local/lib/python2.7/site-packages/gevent/pywsgi.py", line 571, in handle
    handler.handle()
  File "/home/walt/virtualenv/ws/local/lib/python2.7/site-packages/gevent/pywsgi.py", line 180, in handle
    result = self.handle_one_request()
  File "/home/walt/virtualenv/ws/local/lib/python2.7/site-packages/gevent/pywsgi.py", line 314, in handle_one_request
    self.handle_one_response()
  File "/home/walt/virtualenv/ws/local/lib/python2.7/site-packages/geventwebsocket/handler.py", line 26, in handle_one_response
    return self._handle_websocket()
  File "/home/walt/virtualenv/ws/local/lib/python2.7/site-packages/geventwebsocket/handler.py", line 50, in _handle_websocket
    self.log_request()
  File "/home/walt/virtualenv/ws/local/lib/python2.7/site-packages/gevent/pywsgi.py", line 394, in log_request
    log.write(self.format_request() + '\n')
AttributeError: 'Logger' object has no attribute 'write'

I'm running python 2.7.2 on Mint Linux

Answer 1

I get this same bug with gevent-websocket 0.3.4 and gevent 0.13.6 when running the gunicorn -k "geventwebsocket.gunicorn.workers.GeventWebSocketWorker" example:app example.

The problem comes from a mismatch of expectations between gevent and gunicorn. Gevent's pywsgi module expects a logger object which implements a write method, like file objects, stdout, etc. Gunicorn, however, passes in an object which has Logger methods (debug, info, error, critical, warning, etc).

The problem code in pywsgi:

def log_request(self):
    log = self.server.log
    if log:
        log.write(self.format_request() + '\n')

To fix this for myself, I hacked up the lines in a fork of gevent and changed them to the following:

def log_request(self):
    log = self.server.log
    if log:
        if hasattr(log, "info"):
            log.info(self.format_request() + '\n')
        else:
            log.write(self.format_request() + '\n')

Answer 2

used @bkad's code and added to main main app file

def log_request(self):
    log = self.server.log
    if log:
        if hasattr(log, "info"):
            log.info(self.format_request() + '\n')
        else:
            log.write(self.format_request() + '\n')

import gevent
gevent.pywsgi.WSGIHandler.log_request = log_request

to heder so that I wouldn't have to modify 3rd party libraries.

Answer 3

Please use the latest versions of gevent and gevent-websocket on PyPi.