title: Django App Improperly Configured - The app module has multiple filesystem locations
body: <p>I think I've really screwed something up. On my django app (the production one) I pushed a major update and am get an "Internal Server Error" whenever I try to go to my domain. I am getting an error in my uwsgi logs:</p>
  
  <pre><code>*** Starting uWSGI 2.0.8 (64bit) on [Thu Jan 29 00:36:43 2015] ***
  compiled with version: 4.8.2 on 11 December 2014 17:29:38
  os: Linux-3.13.0-41-generic #70-Ubuntu SMP Tue Nov 25 14:40:34 UTC 2014
  nodename: ip-172-31-9-208
  machine: x86_64
  clock source: unix
  detected number of CPU cores: 1
  current working directory: /
  detected binary path: /usr/local/bin/uwsgi
  !!! no internal routing support, rebuild with pcre support !!!
  uWSGI running as root, you can use --uid/--gid/--chroot options
  *** WARNING: you are running uWSGI as root !!! (use the --uid flag) ***
  chdir() to /home/ubuntu/web/app
  *** WARNING: you are running uWSGI without its master process manager ***
  your processes number limit is 15922
  your memory page size is 4096 bytes
  detected max file descriptor number: 1024
  lock engine: pthread robust mutexes
  thunder lock: disabled (you can enable it with --thunder-lock)
  uwsgi socket 0 bound to UNIX address /home/ubuntu/web/ppuwsgi.sock fd 3
  Python version: 3.4.0 (default, Apr 11 2014, 13:08:40)  [GCC 4.8.2]
  Set PythonHome to /home/ubuntu/.virtualenvs/pennypledge
  *** Python threads support is disabled. You can enable it with --enable-threads ***
  Python main interpreter initialized at 0xb57780
  your server socket listen backlog is limited to 100 connections
  your mercy for graceful operations on workers is 60 seconds
  mapped 72768 bytes (71 KB) for 1 cores
  *** Operational MODE: single process ***
  added /home/ubuntu/web/ to pythonpath.
  Traceback (most recent call last):
    File "/home/ubuntu/.virtualenvs/pennypledge/lib/python3.4/site-packages/django/apps/config.py", line 104, in create
      entry = module.default_app_config
  AttributeError: 'module' object has no attribute 'default_app_config'
  
  During handling of the above exception, another exception occurred:
  
  Traceback (most recent call last):
    File "./pennypledge/wsgi.py", line 14, in &lt;module&gt;
      application = get_wsgi_application()
    File "/home/ubuntu/.virtualenvs/pennypledge/lib/python3.4/site-packages/django/core/wsgi.py", line 14, in get_wsgi_application
      django.setup()
    File "/home/ubuntu/.virtualenvs/pennypledge/lib/python3.4/site-packages/django/__init__.py", line 21, in setup 
      apps.populate(settings.INSTALLED_APPS)
    File "/home/ubuntu/.virtualenvs/pennypledge/lib/python3.4/site-packages/django/apps/registry.py", line 85, in populate
      app_config = AppConfig.create(entry)
   File "/home/ubuntu/.virtualenvs/pennypledge/lib/python3.4/site-packages/django/apps/config.py", line 107, in create
      return cls(entry, module)
    File "/home/ubuntu/.virtualenvs/pennypledge/lib/python3.4/site-packages/django/apps/config.py", line 41, in __init__
      self.path = self._path_from_module(app_module)
    File "/home/ubuntu/.virtualenvs/pennypledge/lib/python3.4/site-packages/django/apps/config.py", line 70, in _path_from_module
      "with a 'path' class attribute." % (module, paths))
  django.core.exceptions.ImproperlyConfigured: The app module &lt;module 'ledger' (namespace)&gt; has multiple filesystem locations (['./ledger', '/home/ubuntu/web/app/ledger']); you must configure this app with an AppConfig subclass with a 'path' class attribute.
  unable to load app 0 (mountpoint='') (callable not found or import error)
  *** no app loaded. going in full dynamic mode ***
  *** uWSGI is running in multiple interpreter mode ***
  spawned uWSGI worker 1 (and the only) (pid: 8549, cores: 1)
  --- no python application found, check your startup logs for errors ---
  [pid: 8549|app: -1|req: -1/1] 71.195.197.2 () {42 vars in 828 bytes} [Wed Jan 28 17:36:54 2015] GET / =&gt; generated 21 bytes in 0 msecs (HTTP/1.1 500) 2 headers in 83 bytes (0 switches on core 0)
  --- no python application found, check your startup logs for errors ---
  [pid: 8549|app: -1|req: -1/2] 71.195.197.2 () {42 vars in 814 bytes} [Wed Jan 28 17:36:56 2015] GET /favicon.ico =&gt; generated 21 bytes in 0 msecs (HTTP/1.1 500) 2 headers in 83 bytes (1 switches on core 0)
  --- no python application found, check your startup logs for errors ---
  [pid: 8549|app: -1|req: -1/3] 71.195.197.2 () {38 vars in 640 bytes} [Wed Jan 28 17:37:09 2015] GET / =&gt; generated 21 bytes in 0 msecs (HTTP/1.1 500) 2 headers in 83 bytes (1 switches on core 0)
  --- no python application found, check your startup logs for errors ---
  [pid: 8549|app: -1|req: -1/4] 162.243.163.123 () {40 vars in 751 bytes} [Wed Jan 28 17:37:09 2015] GET /favicon.ico =&gt; generated 21 bytes in 0 msecs (HTTP/1.1 500) 2 headers in 83 bytes (1 switches on core 0)
  --- no python application found, check your startup logs for errors ---
  [pid: 8549|app: -1|req: -1/5] 71.195.197.2 () {40 vars in 748 bytes} [Wed Jan 28 17:37:10 2015] GET /favicon.ico =&gt; generated 21 bytes in 0 msecs (HTTP/1.1 500) 2 headers in 83 bytes (1 switches on core 0)
  --- no python application found, check your startup logs for errors ---
  [pid: 8549|app: -1|req: -1/6] 71.195.197.2 () {38 vars in 591 bytes} [Wed Jan 28 17:37:11 2015] GET /favicon.ico =&gt; generated 21 bytes in 0 msecs (HTTP/1.1 500) 2 headers in 83 bytes (0 switches on core 0)
  </code></pre>
  
  <p>I have no idea what is going on: <code>The app module &lt;module 'ledger' (namespace)&gt; has multiple filesystem locations (['./ledger', '/home/ubuntu/web/app/ledger']); you must configure this app with an AppConfig subclass with a 'path' class attribute.</code>. </p>
  
  <p>Here is my settings.py file:</p>
  
  <pre><code>DEBUG = True
  TEMPLATE_DEBUG = DEBUG
  
  
  # Build paths inside the project like this: os.path.join(BASE_DIR, ...)
  import os
  BASE_DIR = os.path.dirname(os.path.dirname(__file__))
  
  
  # Quick-start development settings - unsuitable for production
  # See https://docs.djangoproject.com/en/1.6/howto/deployment/checklist/
  
  # SECURITY WARNING: keep the secret key used in production secret!
  SECRET_KEY = '&lt;SECRET_KEY&gt;'
  
  
  ALLOWED_HOSTS = ['.example.com','.example2.com']
  
  
  # Application definition
  
  INSTALLED_APPS = (
      'django.contrib.admin',
      'django.contrib.auth',
      'django.contrib.contenttypes',
      'django.contrib.sessions',
      'django.contrib.messages',
      'django.contrib.staticfiles',
      'ledger',
      'extension',
      'plugin',
      'emailmanager',
      'bookmarklet',
      'social.apps.django_app.default',
  )
  
  MIDDLEWARE_CLASSES = (
      'django.contrib.sessions.middleware.SessionMiddleware',
      'django.middleware.common.CommonMiddleware',
      'django.middleware.csrf.CsrfViewMiddleware',
      'django.contrib.auth.middleware.AuthenticationMiddleware',
      'django.contrib.messages.middleware.MessageMiddleware',
      'django.middleware.clickjacking.XFrameOptionsMiddleware',
  )
  
  ROOT_URLCONF = 'pennypledge.urls'
  
  WSGI_APPLICATION = 'pennypledge.wsgi.application'
  
  AUTH_USER_MODEL = 'ledger.User'
  
  
  DATABASES = {
      'default': {
          'ENGINE': 'postgresql_psycopg2', 
          'NAME': 'database',                      # Or path to database file if using sqlite3.
          # The following settings are not used with sqlite3:
          'USER': 'user',
          'PASSWORD': 'password',
          'HOST': '',                      # Empty for localhost through domain sockets or '127.0.0.1' for localhost through TCP.
          'PORT': '',                      # Set to empty string for default.
      }
  }
  
  # Internationalization
  # https://docs.djangoproject.com/en/1.6/topics/i18n/
  
  LANGUAGE_CODE = 'en-us'
  
  TIME_ZONE = 'MST'
  
  USE_I18N = True
  
  USE_L10N = True
  
  USE_TZ = False #I don't think we care about TZ's. If we do then we need to change the deleting of transaction code.
  
  
  STATIC_URL = '/static/'
  
  STATICFILES_DIRS = (
      'C:/pennypledge/pennypledge/static/',
      '/Users/croberts/pennypledge/static/',
  )
  
  TEMPLATE_CONTEXT_PROCESSORS = (
      'django.contrib.auth.context_processors.auth',
      'django.core.context_processors.debug',
      'django.core.context_processors.i18n',
      'django.core.context_processors.media',
      'django.core.context_processors.static',
      'django.core.context_processors.tz',
      'django.contrib.messages.context_processors.messages',
      'social.apps.django_app.context_processors.backends',
      'social.apps.django_app.context_processors.login_redirect',
  )
  
  AUTHENTICATION_BACKENDS = (
      'social.backends.facebook.FacebookOAuth2',
      'ledger.custom_social_auth.YoutubeOAuth2',
      'social.backends.twitter.TwitterOAuth',
      'django.contrib.auth.backends.ModelBackend',
  )
  </code></pre>
  
  <p>Lastly, when I try to checkout a previous version of the code. I get the same problems.</p>
  
  <p><strong>edit - adding uwsgi.conf file</strong></p>
  
  <pre><code># file: /etc/init/ppuwsgi.conf 
  description "uWSGI server for PennyPledge"
  
  start on runlevel [2345]
  stop on runlevel [!2345]
  
  respawn
  exec /usr/local/bin/uwsgi --home /home/ubuntu/web/app/ --socket /home/ubuntu/web/ppuwsgi.sock --chmod-socket=666 --module=pennypledge.wsgi --pythonpath /home/ubuntu/web/ -H /home/ubuntu/.virtualenvs/pennypledge --logto /home/ubuntu/web/logs/uwsgi.log --chdir=/home/ubuntu/web/app --chmod-socket=666
  </code></pre>
  
  <p>I don't know why the problem would be uwsgi's fault as I only updated the Django project.</p>