Added database router. Allows TENANT_APPS and SHARED_APPS to be synced completely separately without messing with Django settings like INSTALLED_APPS or model.meta.managed. Centralized auth is now possible, but cross schema constraints will not be created. This also makes this app thread safe, fixes #2.

docs/install.rst

@@ -21,6 +21,13 @@ Your ``DATABASE_ENGINE`` setting needs to be changed to
             # ..
         }
     }
+
+Add `tenant_schemas.routers.TenantSyncRouter` to your `DATABASE_ROUTERS` setting, so that the correct apps can be synced, depending on what's being synced (shared or tenant).
+
+    DATABASE_ROUTERS = (
+        'tenant_schemas.routers.TenantSyncRouter',
+    )
+  
     
 Add the middleware ``tenant_schemas.middleware.TenantMiddleware`` to the top of ``MIDDLEWARE_CLASSES``, so that each request can be set to use the correct schema.
 

tenant_schemas/management/commands/sync_schemas.py

@@ -1,5 +1,6 @@
 from django.conf import settings
 from django.contrib.contenttypes.models import ContentType
+from django.core.exceptions import ImproperlyConfigured
 from django.db.models import get_apps, get_models
 if "south" in settings.INSTALLED_APPS:
     from south.management.commands.syncdb import Command as SyncdbCommand
@@ -17,13 +18,14 @@ class Command(SyncCommon):
     def handle(self, *args, **options):
         super(Command, self).handle(*args, **options)
 
+        if 'tenant_schemas.routers.TenantSyncRouter' not in settings.DATABASE_ROUTERS:
+            raise ImproperlyConfigured("DATABASE_ROUTERS setting must contain "
+                                       "'tenant_schemas.routers.TenantSyncRouter'.")
+
         if "south" in settings.INSTALLED_APPS:
             self.options["migrate"] = False
 
-        # save original settings
-        for model in get_models(include_auto_created=True):
-            setattr(model._meta, 'was_managed', model._meta.managed)
-
+        # Content types may be different on tenants, so reset the cache
         ContentType.objects.clear_cache()
 
         if self.sync_public:
@@ -31,32 +33,12 @@ class Command(SyncCommon):
         if self.sync_tenant:
             self.sync_tenant_apps(self.schema_name)
 
-        # restore settings
-        for model in get_models(include_auto_created=True):
-            model._meta.managed = model._meta.was_managed
-
-    def _set_managed_apps(self, included_apps):
-        """ sets which apps are managed by syncdb """
-        for model in get_models(include_auto_created=True):
-            model._meta.managed = False
-
-        verbosity = int(self.options.get('verbosity'))
-        for app_model in get_apps():
-            app_name = app_model.__name__.replace('.models', '')
-            if app_name in included_apps:
-                for model in get_models(app_model, include_auto_created=True):
-                    model._meta.managed = model._meta.was_managed
-                    if model._meta.managed and verbosity >= 3:
-                        self._notice("=== Include Model: %s: %s" % (app_name, model.__name__))
-
     def _sync_tenant(self, tenant):
         self._notice("=== Running syncdb for schema: %s" % tenant.schema_name)
         connection.set_tenant(tenant, include_public=False)
         SyncdbCommand().execute(**self.options)
 
     def sync_tenant_apps(self, schema_name=None):
-        apps = self.tenant_apps or self.installed_apps
-        self._set_managed_apps(apps)
         if schema_name:
             tenant = get_tenant_model().objects.filter(schema_name=schema_name).get()
             self._sync_tenant(tenant)
@@ -69,7 +51,5 @@ class Command(SyncCommon):
                 self._sync_tenant(tenant)
 
     def sync_public_apps(self):
-        apps = self.shared_apps or self.installed_apps
-        self._set_managed_apps(apps)
         SyncdbCommand().execute(**self.options)
         self._notice("=== Running syncdb for schema public")

tenant_schemas/routers.py

@@ -0,0 +1,23 @@
+from django.conf import settings
+
+
+class TenantSyncRouter(object):
+    """
+    A router to control which applications will be synced,
+    depending if we are syncing the shared apps or the tenant apps.
+    """
+
+    def allow_syncdb(self, db, model):
+        # the imports below need to be done here else django <1.5 goes crazy
+        # https://code.djangoproject.com/ticket/20704
+        from django.db import connection
+        from tenant_schemas.utils import get_public_schema_name, app_labels
+
+        if connection.schema_name == get_public_schema_name():
+            if model._meta.app_label not in app_labels(settings.SHARED_APPS):
+                return False
+        else:
+            if model._meta.app_label not in app_labels(settings.TENANT_APPS):
+                return False
+
+        return None

tenant_schemas/utils.py

@@ -96,3 +96,10 @@ def schema_exists(schema_name):
     cursor.close()
 
     return exists
+
+
+def app_labels(apps_list):
+    """
+    Returns a list of app labels of the given apps_list
+    """
+    return [app.split('.')[-1] for app in apps_list]