1 files changed, 45 insertions, 0 deletions
diff --git a/django/db/__init__.py b/django/db/__init__.py
new file mode 100644
index 0000000000..317d6059bf
--- /dev/null
+++ b/django/db/__init__.py
@@ -0,0 +1,45 @@
+from django.conf import settings
+from django.core import signals
+from django.dispatch import dispatcher
+
+__all__ = ('backend', 'connection', 'DatabaseError')
+
+if not settings.DATABASE_ENGINE:
+    settings.DATABASE_ENGINE = 'dummy'
+
+try:
+    backend = __import__('django.db.backends.%s.base' % settings.DATABASE_ENGINE, '', '', [''])
+except ImportError, e:
+    # The database backend wasn't found. Display a helpful error message
+    # listing all possible database backends.
+    from django.core.exceptions import ImproperlyConfigured
+    import os
+    backend_dir = os.path.join(__path__[0], 'backends')
+    available_backends = [f for f in os.listdir(backend_dir) if not f.startswith('_') and not f.startswith('.') and not f.endswith('.py') and not f.endswith('.pyc')]
+    available_backends.sort()
+    raise ImproperlyConfigured, "Could not load database backend: %s. Is your DATABASE_ENGINE setting (currently, %r) spelled correctly? Available options are: %s" % \
+        (e, settings.DATABASE_ENGINE, ", ".join(map(repr, available_backends)))
+
+get_introspection_module = lambda: __import__('django.db.backends.%s.introspection' % settings.DATABASE_ENGINE, '', '', [''])
+get_creation_module = lambda: __import__('django.db.backends.%s.creation' % settings.DATABASE_ENGINE, '', '', [''])
+runshell = lambda: __import__('django.db.backends.%s.client' % settings.DATABASE_ENGINE, '', '', ['']).runshell()
+
+connection = backend.DatabaseWrapper()
+DatabaseError = backend.DatabaseError
+
+# Register an event that closes the database connection
+# when a Django request is finished.
+dispatcher.connect(connection.close, signal=signals.request_finished)
+
+# Register an event that resets connection.queries
+# when a Django request is started.
+def reset_queries():
+    connection.queries = []
+dispatcher.connect(reset_queries, signal=signals.request_started)
+
+# Register an event that rolls back the connection
+# when a Django request has an exception.
+def _rollback_on_exception():
+    from django.db import transaction
+    transaction.rollback_unless_managed()
+dispatcher.connect(_rollback_on_exception, signal=signals.got_request_exception)