Fixed #15866, #15850 -- Prevented get_model() and get_models() from returning not-installed models (by default). Thanks adsva for report.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16053 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/contenttypes/models.py

@@ -90,7 +90,8 @@ class ContentType(models.Model):
     def model_class(self):
         "Returns the Python model class for this type of content."
         from django.db import models
-        return models.get_model(self.app_label, self.model)
+        return models.get_model(self.app_label, self.model,
+                                only_installed=False)
 
     def get_object_for_this_type(self, **kwargs):
         """

django/db/models/base.py

@@ -88,7 +88,8 @@ class ModelBase(type):
                 new_class._base_manager = new_class._base_manager._copy_to_model(new_class)
 
         # Bail out early if we have already created this class.
-        m = get_model(new_class._meta.app_label, name, False)
+        m = get_model(new_class._meta.app_label, name,
+                      seed_cache=False, only_installed=False)
         if m is not None:
             return m
 
@@ -201,7 +202,8 @@ class ModelBase(type):
         # the first time this model tries to register with the framework. There
         # should only be one class for each model, so we always return the
         # registered version.
-        return get_model(new_class._meta.app_label, name, False)
+        return get_model(new_class._meta.app_label, name,
+                         seed_cache=False, only_installed=False)
 
     def copy_managers(cls, base_managers):
         # This is in-place sorting of an Options attribute, but that's fine.

django/db/models/fields/related.py

@@ -67,7 +67,8 @@ def add_lazy_relation(cls, field, relation, operation):
     # string right away. If get_model returns None, it means that the related
     # model isn't loaded yet, so we need to pend the relation until the class
     # is prepared.
-    model = get_model(app_label, model_name, False)
+    model = get_model(app_label, model_name,
+                      seed_cache=False, only_installed=False)
     if model:
         operation(field, model, cls)
     else:

django/db/models/loading.py

@@ -25,7 +25,11 @@ class AppCache(object):
         # Keys of app_store are the model modules for each application.
         app_store = SortedDict(),
 
+        # Mapping of installed app_labels to model modules for that app.
+        app_labels = {},
+
         # Mapping of app_labels to a dictionary of model names to model code.
+        # May contain apps that are not installed.
         app_models = SortedDict(),
 
         # Mapping of app_labels to errors raised when trying to import the app.
@@ -66,6 +70,13 @@ class AppCache(object):
         finally:
             self.write_lock.release()
 
+    def _label_for(self, app_mod):
+        """
+        Return app_label for given models module.
+
+        """
+        return app_mod.__name__.split('.')[-2]
+
     def load_app(self, app_name, can_postpone=False):
         """
         Loads the app with the provided fully qualified name, and returns the
@@ -99,6 +110,7 @@ class AppCache(object):
         self.nesting_level -= 1
         if models not in self.app_store:
             self.app_store[models] = len(self.app_store)
+            self.app_labels[self._label_for(models)] = models
         return models
 
     def app_cache_ready(self):
@@ -146,7 +158,8 @@ class AppCache(object):
         self._populate()
         return self.app_errors
 
-    def get_models(self, app_mod=None, include_auto_created=False, include_deferred=False):
+    def get_models(self, app_mod=None,
+                   include_auto_created=False, include_deferred=False):
         """
         Given a module containing models, returns a list of the models.
         Otherwise returns a list of all installed models.
@@ -166,20 +179,26 @@ class AppCache(object):
             pass
         self._populate()
         if app_mod:
-            app_list = [self.app_models.get(app_mod.__name__.split('.')[-2], SortedDict())]
+            if app_mod in self.app_store:
+                app_list = [self.app_models.get(self._label_for(app_mod),
+                                                SortedDict())]
+            else:
+                app_list = []
         else:
-            app_list = self.app_models.itervalues()
+            app_list = [self.app_models.get(app_label, SortedDict())
+                        for app_label in self.app_labels.iterkeys()]
         model_list = []
         for app in app_list:
             model_list.extend(
                 model for model in app.values()
-                if ((not model._deferred or include_deferred)
-                    and (not model._meta.auto_created or include_auto_created))
+                if ((not model._deferred or include_deferred) and
+                    (not model._meta.auto_created or include_auto_created))
             )
         self._get_models_cache[cache_key] = model_list
         return model_list
 
-    def get_model(self, app_label, model_name, seed_cache=True):
+    def get_model(self, app_label, model_name,
+                  seed_cache=True, only_installed=True):
         """
         Returns the model matching the given app_label and case-insensitive
         model_name.
@@ -188,6 +207,8 @@ class AppCache(object):
         """
         if seed_cache:
             self._populate()
+        if only_installed and app_label not in self.app_labels:
+            return None
         return self.app_models.get(app_label, SortedDict()).get(model_name.lower())
 
     def register_models(self, app_label, *models):

tests/regressiontests/admin_scripts/tests.py

@@ -1023,7 +1023,11 @@ class ManageValidate(AdminScriptTestCase):
     def test_app_with_import(self):
         "manage.py validate does not raise errors when an app imports a base class that itself has an abstract base"
         self.write_settings('settings.py',
-            apps=['admin_scripts.app_with_import', 'django.contrib.comments'],
+            apps=['admin_scripts.app_with_import',
+                  'django.contrib.comments',
+                  'django.contrib.auth',
+                  'django.contrib.contenttypes',
+                  'django.contrib.sites'],
             sdict={'DEBUG': True})
         args = ['validate']
         out, err = self.run_manage(args)

tests/regressiontests/app_loading/not_installed/models.py

@@ -0,0 +1,5 @@
+from django.db import models
+
+
+class NotInstalledModel(models.Model):
+    pass

tests/regressiontests/app_loading/tests.py

@@ -4,7 +4,7 @@ import sys
 import time
 
 from django.conf import Settings
-from django.db.models.loading import cache, load_app
+from django.db.models.loading import cache, load_app, get_model, get_models
 from django.utils.unittest import TestCase
 
 
@@ -81,3 +81,24 @@ class EggLoadingTest(TestCase):
             # Make sure the message is indicating the actual
             # problem in the broken app.
             self.assertTrue("modelz" in e.args[0])
+
+
+class GetModelsTest(TestCase):
+    def setUp(self):
+        import not_installed.models
+        self.not_installed_module = not_installed.models
+
+
+    def test_get_model_only_returns_installed_models(self):
+        self.assertEqual(
+            get_model("not_installed", "NotInstalledModel"), None)
+
+
+    def test_get_models_only_returns_installed_models(self):
+        self.assertFalse(
+            "NotInstalledModel" in
+            [m.__name__ for m in get_models()])
+
+
+    def test_get_models_with_app_label_only_returns_installed_models(self):
+        self.assertEqual(get_models(self.not_installed_module), [])