class 'psycopg2.InterfaceError': connexion déjà fermée

Question

Je tire sur mes cheveux et suis sur le point de faire quelque chose de sale.

Je cours nginx + django + postgresql. La moitié du temps, je suis en train de tester mon site et ouvrir une page, je reçois les éléments suivants:

<class 'psycopg2.InterfaceError'> Python 2.7.2: /home/webapp/newavenue/bin/python 
Fri Feb 24 08:28:58 2012 
A problem occurred in a Python script. Here is the sequence of function calls leading up to the error, in the order they occurred. 

/home/webapp/newavenue/lib/python2.7/site-packages/flup/server/fcgi_base.py in run(self=<flup.server.fcgi_base.Request object>) 
    572    
    573   try: 
=> 574    protocolStatus, appStatus = self.server.handler(self) 
    575   except: 
    576    traceback.print_exc(file=self.stderr) 
protocolStatus undefined, appStatus undefined, self = <flup.server.fcgi_base.Request object>, self.server = <flup.server.fcgi_fork.WSGIServer object>, self.server.handler = <bound method WSGIServer.handler of <flup.server.fcgi_fork.WSGIServer object>> 
/home/webapp/newavenue/lib/python2.7/site-packages/flup/server/fcgi_base.py in handler(self=<flup.server.fcgi_fork.WSGIServer object>, req=<flup.server.fcgi_base.Request object>) 
    1157   try: 
    1158    try: 
=> 1159     result = self.application(environ, start_response) 
    1160     try: 
    1161      for data in result: 
result = None, self = <flup.server.fcgi_fork.WSGIServer object>, self.application = <django.core.handlers.wsgi.WSGIHandler object>, environ = {'CONTENT_LENGTH': '', 'CONTENT_TYPE': '', 'HTTP_ACCEPT': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8', 'HTTP_ACCEPT_CHARSET': 'ISO-8859-1,utf-8;q=0.7,*;q=0.3', 'HTTP_ACCEPT_ENCODING': 'gzip,deflate,sdch', 'HTTP_ACCEPT_LANGUAGE': 'en-US,en;q=0.8', 'HTTP_CACHE_CONTROL': 'max-age=0', 'HTTP_CONNECTION': 'keep-alive', 'HTTP_COOKIE': 'csrftoken=8a0176b368b17af00a8563b5f95b134b; sess...e5bdd0d0a4e3092e7a9abd0029c02; django_language=en', 'HTTP_HOST': 'newavedev.zapto.org', ...}, start_response = <function start_response> 
/home/webapp/newavenue/lib/python2.7/site-packages/django/core/handlers/wsgi.py in __call__(self=<django.core.handlers.wsgi.WSGIHandler object>, environ={'CONTENT_LENGTH': '', 'CONTENT_TYPE': '', 'HTTP_ACCEPT': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8', 'HTTP_ACCEPT_CHARSET': 'ISO-8859-1,utf-8;q=0.7,*;q=0.3', 'HTTP_ACCEPT_ENCODING': 'gzip,deflate,sdch', 'HTTP_ACCEPT_LANGUAGE': 'en-US,en;q=0.8', 'HTTP_CACHE_CONTROL': 'max-age=0', 'HTTP_CONNECTION': 'keep-alive', 'HTTP_COOKIE': 'csrftoken=8a0176b368b17af00a8563b5f95b134b; sess...e5bdd0d0a4e3092e7a9abd0029c02; django_language=en', 'HTTP_HOST': 'newavedev.zapto.org', ...}, start_response=<function start_response>) 
    272     response = self.get_response(request) 
    273   finally: 
=> 274    signals.request_finished.send(sender=self.__class__) 
    275 
    276   try: 
global signals = <module 'django.core.signals' from '/home/webapp...python2.7/site-packages/django/core/signals.pyc'>, signals.request_finished = <django.dispatch.dispatcher.Signal object>, signals.request_finished.send = <bound method Signal.send of <django.dispatch.dispatcher.Signal object>>, sender undefined, self = <django.core.handlers.wsgi.WSGIHandler object>, self.__class__ = <class 'django.core.handlers.wsgi.WSGIHandler'> 
/home/webapp/newavenue/lib/python2.7/site-packages/django/dispatch/dispatcher.py in send(self=<django.dispatch.dispatcher.Signal object>, sender=<class 'django.core.handlers.wsgi.WSGIHandler'>, **named={}) 
    170 
    171   for receiver in self._live_receivers(_make_id(sender)): 
=> 172    response = receiver(signal=self, sender=sender, **named) 
    173    responses.append((receiver, response)) 
    174   return responses 
response undefined, receiver = <function close_connection>, signal undefined, self = <django.dispatch.dispatcher.Signal object>, sender = <class 'django.core.handlers.wsgi.WSGIHandler'>, named = {} 
/home/webapp/newavenue/lib/python2.7/site-packages/django/db/__init__.py in close_connection(**kwargs={'sender': <class 'django.core.handlers.wsgi.WSGIHandler'>, 'signal': <django.dispatch.dispatcher.Signal object>}) 
    83 def close_connection(**kwargs): 
    84  for conn in connections.all(): 
=> 85   conn.close() 
    86 signals.request_finished.connect(close_connection) 
    87 
conn = <django.db.backends.postgresql_psycopg2.base.DatabaseWrapper object>, conn.close = <bound method DatabaseWrapper.close of <django.d...postgresql_psycopg2.base.DatabaseWrapper object>> 
/home/webapp/newavenue/lib/python2.7/site-packages/django/db/backends/__init__.py in close(self=<django.db.backends.postgresql_psycopg2.base.DatabaseWrapper object>) 
    242  def close(self): 
    243   if self.connection is not None: 
=> 244    self.connection.close() 
    245    self.connection = None 
    246 
self = <django.db.backends.postgresql_psycopg2.base.DatabaseWrapper object>, self.connection = <connection object at 0x1d37130; dsn: 'dbname=ne...er=postgres host=localhost port=5432', closed: 2>, self.connection.close = <built-in method close of psycopg2._psycopg.connection object> 
<class 'psycopg2.InterfaceError'>: connection already closed 
     args = ('connection already closed',) 
     cursor = None 
     message = 'connection already closed' 
     pgcode = None 
     pgerror = None 

Le serveur est exécuté avec les éléments suivants pour générer le rapport flup de retraçage précédent:

python manage.py runfcgi host=127.0.0.1 port=8000 debug=False 

pourrait Je viens de contourner cela en patcher quelque chose comme: "try: self.connection.close(), sauf: passer" autour de cette ligne fautive? Cela marcherait probablement mais je pense que cela semble sale (déconner avec le noyau) et je voudrais essayer de trouver une solution alternative.

Edit: Considérant l'approche de ce gars-là aussi: le commenter sur: http://osdir.com/ml/DjangoUsers/2009-04/msg01647.html

Answer 1

Je pense que je suis autour du problème. Ce n'est pas vraiment une solution à la configuration de flup-psycopg2 mais une alternative évitant le flou. Je suis passé de l'utilisation de fcgi à gunicorn et a également enveloppé la ligne self.connection.close() avec "try: self.connection.close(), sauf: pass". Cela a également résolu un problème 502 Bad Gateway que j'avais avec nginx.

En outre, il semble que mon site fonctionne un peu plus vite, ce qui est toujours un effet secondaire doux.