Merge pull request django-cms#3360 from mmarzantowicz/feature/app_setup_refactor

Refactored code that checks settings and dependencies

Author: digi604

cms/apps.py

@@ -1,12 +1,12 @@
 from django.apps import AppConfig
 from django.utils.translation import ugettext_lazy as _
 
+from cms.utils.setup import setup
+
 
 class CMSConfig(AppConfig):
     name = 'cms'
     verbose_name = _("django CMS")
 
     def ready(self):
-        from cms.models import validate_dependencies, validate_settings
-        validate_dependencies()
-        validate_settings()
+        setup()

cms/models/__init__.py

@@ -1,8 +1,4 @@
 # -*- coding: utf-8 -*-
-from django.conf import settings as d_settings
-from cms.utils.compat import DJANGO_1_6
-from cms.utils.compat.dj import is_installed
-
 from .settingmodels import *  # nopyflakes
 from .pagemodel import *  # nopyflakes
 from .permissionmodels import *  # nopyflakes
@@ -16,22 +12,9 @@
 from cms import signals as s_import  # nopyflakes
 
 
-def validate_settings():
-    if "django.core.context_processors.request" not in d_settings.TEMPLATE_CONTEXT_PROCESSORS:
-        raise ImproperlyConfigured('django-cms needs django.core.context_processors.request in settings.TEMPLATE_CONTEXT_PROCESSORS to work correctly.')
-    if not is_installed('mptt'):
-        raise ImproperlyConfigured('django-cms needs django-mptt installed.')
-    if 'cms.middleware.multilingual.MultilingualURLMiddleware' in d_settings.MIDDLEWARE_CLASSES and 'django.middleware.locale.LocaleMiddleware' in d_settings.MIDDLEWARE_CLASSES:
-        raise ImproperlyConfigured('django-cms MultilingualURLMiddleware replaces django.middleware.locale.LocaleMiddleware! Please remove django.middleware.locale.LocaleMiddleware from your MIDDLEWARE_CLASSES settings.')
-
-
-def validate_dependencies():
-    # check for right version of reversions
-    if is_installed('reversion'):
-        from reversion.admin import VersionAdmin
-        if not hasattr(VersionAdmin, 'get_urls'):
-            raise ImproperlyConfigured('django-cms requires never version of reversion (VersionAdmin must contain get_urls method)')
+# Temporary support for django version 1.6 and below
+from cms.utils.compat import DJANGO_1_6
 
 if DJANGO_1_6:
-    validate_dependencies()
-    validate_settings()
+    from cms.utils.setup import setup
+    setup()

cms/utils/setup.py

@@ -0,0 +1,33 @@
+from django.conf import settings
+from django.core.exceptions import ImproperlyConfigured
+
+from cms.utils.compat.dj import is_installed as app_is_installed
+
+
+def validate_dependencies():
+    """
+    Check for installed apps, their versions and configuration options
+    """
+    if not app_is_installed('mptt'):
+        raise ImproperlyConfigured('django CMS requires django-mptt package.')
+
+    if not app_is_installed('reversion'):
+        from reversion.admin import VersionAdmin
+        if not hasattr(VersionAdmin, 'get_urls'):
+            raise ImproperlyConfigured('django CMS requires newer version of reversion (VersionAdmin must contain get_urls method)')
+
+
+def validate_settings():
+    """
+    Check project settings file for required options
+    """
+    if 'django.core.context_processors.request' not in settings.TEMPLATE_CONTEXT_PROCESSORS:
+        raise ImproperlyConfigured('django CMS requires django.core.context_processors.request in settings.TEMPLATE_CONTEXT_PROCESSORS to work correctly.')
+
+
+def setup():
+    """
+    Gather all checks and validations
+    """
+    validate_dependencies()
+    validate_settings()