feat(db): Implement config update and replace methods for database connectors

Author: Zhe Yu

src/vectorcode/database/base.py

@@ -1,6 +1,7 @@
+import asyncio
 import logging
 from abc import ABC, abstractmethod
-from typing import Optional, Sequence
+from typing import Optional, Self, Sequence
 
 from chromadb import EmbeddingFunction
 from numpy.typing import NDArray
@@ -117,3 +118,35 @@ async def drop(self, collection_path: str):
         Delete a collection from the database.
         """
         pass
+
+    def _check_new_config(self, new_config: Config) -> bool:
+        """
+        Verify that the `new_config` is a valid one for updating.
+        """
+        assert isinstance(new_config, Config), "`new_config` is not a `Config` object."
+        return (
+            new_config.db_type == self._configs.db_type
+            and new_config.db_params == self._configs.db_params
+        )
+
+    def update_config(self, new_config: Config) -> Self:
+        assert self._check_new_config(new_config), (
+            "The new config has different database configs."
+        )
+
+        # no need to make this one async
+        try:
+            loop = asyncio.get_running_loop()
+        except RuntimeError:
+            loop = asyncio.new_event_loop()
+            asyncio.set_event_loop(loop)
+
+        self._configs = loop.run_until_complete(self._configs.merge_from(new_config))
+        return self
+
+    def replace_config(self, new_config: Config) -> Self:
+        assert self._check_new_config(new_config), (
+            "The new config has different database configs."
+        )
+        self._configs = new_config
+        return self