feat(cli): implement database builder with lazy import

Author: Davidyz

src/vectorcode/database/__init__.py

@@ -0,0 +1,27 @@
+import logging
+from typing import Optional, Type
+
+from vectorcode.cli_utils import Config
+from vectorcode.database.base import DatabaseConnectorBase
+
+logger = logging.getLogger(name=__name__)
+
+
+def get_database_connector(config: Config) -> DatabaseConnectorBase:
+    """
+    It's CRUCIAL to keep the `import`s of the database connectors in the branches.
+    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.
+
+    """
+    cls: Optional[Type[DatabaseConnectorBase]] = None
+
+    match config.db_type:
+        case "ChromaDB0Connector":
+            from vectorcode.database.chroma0 import ChromaDB0Connector
+
+            cls = ChromaDB0Connector
+        case _:
+            raise ValueError(f"Unrecognised database type: {config.db_type}")
+
+    return cls.create(config)

src/vectorcode/subcommands/drop.py

@@ -1,14 +1,14 @@
 import logging
 
 from vectorcode.cli_utils import Config
-from vectorcode.database.chroma0 import ChromaDB0Connector
+from vectorcode.database import get_database_connector
 from vectorcode.database.errors import CollectionNotFoundError
 
 logger = logging.getLogger(name=__name__)
 
 
 async def drop(config: Config) -> int:
-    database = ChromaDB0Connector(config)
+    database = get_database_connector(config)
     try:
         await database.drop(str(config.project_root))
         if not config.pipe: