app/main.py

   1 #!/usr/bin/python2.5
   2 #
   3 # Copyright 2008 the Melange authors.
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at
   8 #
   9 #   http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16
  17 """Main Melange module with profiling support.
  18 """
  19
  20 __authors__ = [
  21   # alphabetical order by last name, please
  22   '"Augie Fackler" <durin42@gmail.com>',
  23   ]
  24
  25
  26 import logging
  27 import os
  28 import sys
  29
  30 from google.appengine.ext.webapp import util
  31
  32
  33 # Remove the standard version of Django.
  34 for k in [k for k in sys.modules if k.startswith('django')]:
  35   del sys.modules[k]
  36
  37 # Force sys.path to have our own directory first, in case we want to import
  38 # from it. This lets us replace the built-in Django
  39 sys.path.insert(0, os.path.abspath(os.path.dirname(__file__)))
  40
  41 sys.path.insert(0, os.path.abspath('django.zip'))
  42
  43 ultimate_sys_path = None
  44
  45 # Force Django to reload its settings.
  46 from django.conf import settings
  47 settings._target = None
  48
  49 # Must set this env var before importing any part of Django
  50 os.environ['DJANGO_SETTINGS_MODULE'] = 'settings'
  51
  52 import django.core.handlers.wsgi
  53 import django.core.signals
  54 import django.db
  55
  56 # Log errors.
  57 def log_exception(*args, **kwds):
  58   """Function used for logging exceptions.
  59   """
  60   logging.exception('Exception in request:')
  61
  62 # Log all exceptions detected by Django.
  63 django.core.signals.got_request_exception.connect(log_exception)
  64
  65 # Unregister the rollback event handler.
  66 django.core.signals.got_request_exception.disconnect(
  67     django.db._rollback_on_exception)
  68
  69
  70 def profile_main_as_html():
  71   """Main program for profiling. Profiling data added as HTML to the page.
  72   """
  73   import cProfile
  74   import pstats
  75   import StringIO
  76
  77   prof = cProfile.Profile()
  78   prof = prof.runctx('real_main()', globals(), locals())
  79   stream = StringIO.StringIO()
  80   stats = pstats.Stats(prof, stream=stream)
  81   # stats.strip_dirs()  # Don't; too many modules are named __init__.py.
  82
  83   # 'time', 'cumulative' or 'calls'
  84   stats.sort_stats('time')
  85
  86   # Optional arg: how many to print
  87   stats.print_stats()
  88   # The rest is optional.
  89   # stats.print_callees()
  90   # stats.print_callers()
  91   print '\n<hr>'
  92   print '<h1>Profile data</h1>'
  93   print '<pre>'
  94   print stream.getvalue()[:1000000]
  95   print '</pre>'
  96
  97
  98 def profile_main_as_logs():
  99   """Main program for profiling. Profiling data logged.
 100   """
 101   import cProfile
 102   import pstats
 103   import StringIO
 104
 105   prof = cProfile.Profile()
 106   prof = prof.runctx("real_main()", globals(), locals())
 107   stream = StringIO.StringIO()
 108   stats = pstats.Stats(prof, stream=stream)
 109   stats.sort_stats('time')  # Or cumulative
 110   stats.print_stats(80)  # 80 = how many to print
 111   # The rest is optional.
 112   # stats.print_callees()
 113   # stats.print_callers()
 114   logging.info("Profile data:\n%s", stream.getvalue())
 115
 116
 117 def real_main():
 118   """Main program without profiling.
 119   """
 120   global ultimate_sys_path
 121   if ultimate_sys_path is None:
 122     ultimate_sys_path = list(sys.path)
 123   else:
 124     sys.path[:] = ultimate_sys_path
 125
 126   # Create a Django application for WSGI.
 127   application = django.core.handlers.wsgi.WSGIHandler()
 128
 129   # Run the WSGI CGI handler with that application.
 130   util.run_wsgi_app(application)
 131
 132 main = real_main
 133
 134 if __name__ == '__main__':
 135   main()