docs about database connectors.

Author: Zhe Yu

src/vectorcode/database/__init__.py

@@ -13,11 +13,13 @@ def get_database_connector(config: Config) -> DatabaseConnectorBase:
     This allow them to be lazy-imported. This also allow us to keep the main package
     lightweight because we don't have to include dependencies for EVERY database.
 
+    > Raises a `ValueError` in case the database connector is not supported.
     """
     cls: Optional[Type[DatabaseConnectorBase]] = None
 
     if not config.db_type.endswith("Connector"):
         config.db_type = f"{config.db_type}Connector"
+        logger.debug(f"Correcting the name of the db connector to {config.db_type}")
 
     match config.db_type:
         case "ChromaDB0Connector":
@@ -28,3 +30,6 @@ def get_database_connector(config: Config) -> DatabaseConnectorBase:
             raise ValueError(f"Unrecognised database type: {config.db_type}")
 
     return cls.create(config)
+
+
+__all__ = ["get_database_connector"]

src/vectorcode/database/base.py

@@ -19,6 +19,28 @@
 logger = logging.getLogger(name=__name__)
 
 
+"""
+For developers:
+
+To implement a custom database connector, you should inherit the following 
+`DatabaseConnectorBase` class and implement ALL abstract methods. 
+
+You should also try to wrap the exceptions with the ones in 
+`src/vectorcode/database/errors.py` where appropriate, because this helps the 
+CLI/LSP/MCP interfaces to handle some common edge cases. To do this, you should do the following in a try-except block:
+```python
+from vectorcode.database.errors import CollectionNotFoundError
+
+try:
+    some_action_here()
+except SomeCustomException as e:
+    raise CollectionNotFoundError("The collection was not found.") from e
+```
+This will preserve the correct call stack in the error message and makes debugging 
+easier.
+"""
+
+
 class DatabaseConnectorBase(ABC):  # pragma: nocover
     @classmethod
     def create(cls, configs: Config):