Ticket #5454: user_backend_r6284.patch

django/db/__init__.py

@@ -1 +1 @@
 from django.conf import settings
 from django.core import signals
 from django.dispatch import dispatcher
+from django.utils.functional import curry
 
 __all__ = ('backend', 'connection', 'DatabaseError', 'IntegrityError')
 
@@ -8 +9 @@
     settings.DATABASE_ENGINE = 'dummy'
 
 try:
-    backend = __import__('django.db.backends.%s.base' % settings.DATABASE_ENGINE, {}, {}, [''])
+    import_path = 'django.db.backends.'
+    backend = __import__('%s%s.base' % (import_path, 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()
-    if settings.DATABASE_ENGINE not in available_backends:
-        raise ImproperlyConfigured, "%r isn't an available database backend. Available options are: %s" % \
-            (settings.DATABASE_ENGINE, ", ".join(map(repr, available_backends)))
-    else:
-        raise # If there's some other error, this must be an error in Django itself.
+    try:
+        import_path = ''
+        backend = __import__('%s%s.base' % (import_path, settings.DATABASE_ENGINE), {}, {}, [''])
+    except ImportError, e_user:
+        # 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()
+        if settings.DATABASE_ENGINE not in available_backends:
+            raise ImproperlyConfigured, "%r isn't an available database backend. Available options are: %s" % \
+                (settings.DATABASE_ENGINE, ", ".join(map(repr, available_backends)))
+        else:
+            raise # If there's some other error, this must be an error in Django itself.
 
-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()
+def get_module_curried(import_path='', module_name=''):
+    return __import__('%s%s.%s' % (import_path, settings.DATABASE_ENGINE, module_name), {}, {}, [''])
 
+get_introspection_module = curry(get_module_curried, import_path=import_path, module_name='introspection')
+get_creation_module = curry(get_module_curried, import_path=import_path, module_name='creation')
+runshell = curry(get_module_curried, import_path=import_path)(module_name='client').runshell
+
 connection = backend.DatabaseWrapper(**settings.DATABASE_OPTIONS)
 DatabaseError = backend.DatabaseError
 IntegrityError = backend.IntegrityError