feat: Spanner Implementation for Vector Store (#10)

* feat: Adding Vector Store Implementation for Spanner

- Static Utility to create a table to store vector embeddings
- Automatic Dialect Detection for GSQL and PG
- Similarity Search & Maximal Marginal Relevance Search
- Add documents and texts

* feat: Validating Types, Columns at the time of VectorStore initialization & also while creating new table through static utility.

* feat: Delete Vector embeddings through documents.

* style: format and lint

* feat: Adding init file to export VectorStore

* feat: Adding delete to dynamically generate SQL for each row.

* feat: Adding full support for staleness with multiple options like read_timestamp and min and exact staleness.

* feat: Addressing review comments and adding data class for indexes.

* feat: Adding support for secondary indexes.

* feat: exporting secondary indexes.

* style: lint

* feat: Initiating client with user agent.

* feat: Addressing review comments.

* style: lint

* style: lint

* style: lint

* test: Vector Store Implementation Integration Tests (#16)

* test: Adding integration tests for static utility to create vector embeddings table.

* test: Adding add,search,delete integration tests for VectorStore.

* test: lint

* test: lint

* style: lint

* style: lint

* Empty-Commit to trigger tests

* test: addressing review comments.

* test: test fix

* adding bs4 in test dependencies

---------

Co-authored-by: Averi Kitsch <[email protected]>

* replacing - with :

* style: lint

* minor changes.

---------

Co-authored-by: Averi Kitsch <[email protected]>

pyproject.toml

@@ -22,6 +22,7 @@ Changelog = "https://github.com/googleapis/langchain-google-spanner-python/blob/
 [project.optional-dependencies]
 test = [
     "black[jupyter]==23.12.0",
+    "bs4==0.0.2",
     "isort==5.13.2",
     "mypy==1.7.1",
     "pytest==7.4.4",

src/langchain_google_spanner/__init__.py

@@ -13,7 +13,22 @@
 # limitations under the License.
 
 from langchain_google_spanner.chat_message_history import SpannerChatMessageHistory
+from langchain_google_spanner.vector_store import (
+    DistanceStrategy,
+    QueryParameters,
+    SecondaryIndex,
+    SpannerVectorStore,
+    TableColumn,
+)
 
 from .version import __version__
 
-__all__ = ["__version__", "SpannerChatMessageHistory"]
+__all__ = [
+    "__version__",
+    "SpannerChatMessageHistory",
+    "SpannerVectorStore",
+    "TableColumn",
+    "SecondaryIndex",
+    "QueryParameters",
+    "DistanceStrategy",
+]