Add a new exception for MongoDB Authentication errors

bigchaindb/backend/exceptions.py

@@ -9,6 +9,10 @@ class ConnectionError(BackendError):
     """Exception raised when the connection to the backend fails."""
 
 
+class AuthenticationError(ConnectionError):
+    """Exception raised when MongoDB Authentication fails"""
+
+
 class OperationError(BackendError):
     """Exception raised when a backend operation fails."""
 

bigchaindb/backend/mongodb/connection.py

@@ -8,7 +8,8 @@ from bigchaindb.utils import Lazy
 from bigchaindb.common.exceptions import ConfigurationError
 from bigchaindb.backend.exceptions import (DuplicateKeyError,
                                            OperationError,
-                                           ConnectionError)
+                                           ConnectionError,
+                                           AuthenticationError)
 from bigchaindb.backend.connection import Connection
 
 logger = logging.getLogger(__name__)
@@ -83,6 +84,8 @@ class MongoDBConnection(Connection):
         # `initialize_replica_set` might raise `ConnectionFailure` or `OperationFailure`.
         except (pymongo.errors.ConnectionFailure,
                 pymongo.errors.OperationFailure) as exc:
+            if "Authentication fail" in str(exc):
+                raise AuthenticationError() from exc
             raise ConnectionError() from exc