config changes

bigchaindb/backend/connection.py

@@ -6,8 +6,8 @@ from bigchaindb.common.exceptions import ConfigurationError
 
 
 BACKENDS = {
-    'rethinkdb': 'bigchaindb.backend.rethinkdb.connection.RethinkDBConnection',
     'mongodb': 'bigchaindb.backend.mongodb.connection.MongoDBConnection',
+    'rethinkdb': 'bigchaindb.backend.rethinkdb.connection.RethinkDBConnection'
 }
 
 logger = logging.getLogger(__name__)

bigchaindb/backend/mongodb/__init__.py

@@ -1,2 +1,22 @@
+"""MongoDB backend implementation.
+
+Contains a MongoDB-specific implementation of the
+:mod:`~bigchaindb.backend.changefeed`, :mod:`~bigchaindb.backend.query`, and
+:mod:`~bigchaindb.backend.schema` interfaces.
+
+You can specify BigchainDB to use MongoDB as its database backend by either
+setting ``database.backend`` to ``'rethinkdb'`` in your configuration file, or
+setting the ``BIGCHAINDB_DATABASE_BACKEND`` environment variable to
+``'rethinkdb'``.
+
+If configured to use MongoDB, BigchainDB will automatically return instances
+of :class:`~bigchaindb.backend.rethinkdb.MongoDBConnection` for
+:func:`~bigchaindb.backend.connection.connect` and dispatch calls of the
+generic backend interfaces to the implementations in this module.
+"""
+
 # Register the single dispatched modules on import.
-from bigchaindb.backend.mongodb import schema, query  # noqa
+from bigchaindb.backend.mongodb import changefeed, schema, query  # noqa
+
+# MongoDBConnection should always be accessed via
+# ``bigchaindb.backend.connect()``.