My settings.py is called 4 times - any ideas why? - django

Question

When I start the local dev server (./manage runserver) the settings.py is run four times. I noticed that, because a error/debug message is printed four times.
Any ideas how this can come? I don't even have an idea where to start looking. It's important for me because I'm struggling with the setup of Sentry, which doesn't report any errors of the site the way it is installed now.
Update:
I checked the imported module for import settings, there are none in my apps.
Then I added
import traceback; traceback.print_stack(); print
to settings.py. The result is:
File "./manage.py", line 5, in <module>
import settings # Assumed to be in the same directory.
File "(...)/myapp/settings.py", line 4, in <module>
import traceback; traceback.print_stack(); print
File "./manage.py", line 12, in <module>
execute_manager(settings)
(...)
File "(...)/site-packages/django/conf/__init__.py", line 73, in __init__
mod = importlib.import_module(self.SETTINGS_MODULE)
File "(...)/site-packages/django/utils/importlib.py", line 35, in import_module
__import__(name)
File "(...)/myapp/../myapp/settings.py", line 4, in <module>
import traceback; traceback.print_stack(); print
File "./manage.py", line 5, in <module>
import settings # Assumed to be in the same directory.
File "(...)/myapp/settings.py", line 4, in <module>
import traceback; traceback.print_stack(); print
File "./manage.py", line 12, in <module>
execute_manager(settings)
(...)
File "(...)/site-packages/django/conf/__init__.py", line 73, in __init__
mod = importlib.import_module(self.SETTINGS_MODULE)
File "(...)/site-packages/django/utils/importlib.py", line 35, in import_module
__import__(name)
File "(...)/myapp/../myapp/settings.py", line 4, in <module>
import traceback; traceback.print_stack(); print
Is that intended behaviour? If not, how can I find my error?

Answer 1

It's being accessed via different entries in sys.path. You should never attempt to import settings yourself; import django.conf.settings instead.

Answer 2

This behavior actually occurs in brand new Django 1.3 Projects. When the development server is started for the first time, it does four imports:
$ django-admin.py startproject test_project
$ cd test_project/
# settings.py
print "importing settings.py"
...
$ python manage.py runserver
importing settings.py
importing settings.py
importing settings.py
importing settings.py
Validating models...
0 errors found
Django version 1.3, using settings 'test_project.settings'
Development server is running at http://127.0.0.1:8000/
Quit the server with CONTROL-C.
If you edit a file with the development server running, it only does two imports:
$ touch settings.py
Output:
importing settings.py
importing settings.py
Validating models...
0 errors found
Django version 1.3, using settings 'test_project.settings'
Development server is running at http://127.0.0.1:8000/
Quit the server with CONTROL-C.
I'm not sure why it does this, or if it does it on non-development servers. But the behavior does appear to be normal.
If you track imports in settings.py, it doesn't persist values across the multiple imports:
# settings.py
import_count = 0
import_count += 1
print "import count: %d" % import_count
Fresh start:
$ python manage.py runserver
import count: 1
import count: 1
import count: 1
import count: 1
Validating models...
Changed a file:
import count: 1
import count: 1
Validating models...
So maybe it's just reading the file to configure itself, and verify that everything is OK, before importing it for the final time and actually using it?