🚀 feat(langflow): add support for MongoDB Atlas Vector Search in vectorstores

✨ feat(langflow): add support for search_kwargs field in VectorStoreFrontendNode
The changes add support for MongoDB Atlas Vector Search in the vectorstores. The `MongoDBAtlasVectorSearch` class is now imported and initialized in `vector_store.py`. The `initialize_mongodb` function is added to initialize the MongoDB Atlas Vector Search class. The `VectorStoreFrontendNode` class is updated to add the `mongodb_atlas_cluster_uri`, `collection_name`, and `db_name` fields. The `search_kwargs` field is also added to the `VectorStoreFrontendNode` class to allow users to pass additional search parameters to the vector store.

src/backend/langflow/config.yaml

@@ -133,6 +133,7 @@ vectorstores:
   - FAISS
   - Pinecone
   - SupabaseVectorStore
+  - MongoDBAtlasVectorSearch
 wrappers:
   - RequestsWrapper
   # - ChatPromptTemplate

src/backend/langflow/interface/initialize/vector_store.py

@@ -7,7 +7,9 @@ from langchain.vectorstores import (
     FAISS,
     Weaviate,
     SupabaseVectorStore,
+    MongoDBAtlasVectorSearch,
 )
+import os
 
 
 def docs_in_params(params: dict) -> bool:
@@ -18,6 +20,38 @@ def docs_in_params(params: dict) -> bool:
     )
 
 
+def initialize_mongodb(class_object: Type[MongoDBAtlasVectorSearch], params: dict):
+    """Initialize mongodb and return the class object"""
+
+    MONGODB_ATLAS_CLUSTER_URI = params.get("mongodb_atlas_cluster_uri")
+    if not MONGODB_ATLAS_CLUSTER_URI:
+        raise ValueError("Mongodb atlas cluster uri must be provided in the params")
+    from pymongo import MongoClient
+
+    client = MongoClient(MONGODB_ATLAS_CLUSTER_URI)
+    db_name = "lanchain_db"
+    collection_name = "langchain_col"
+    collection = client[db_name][collection_name]
+    index_name = "langchain_demo"
+    if not docs_in_params(params):
+        # __init__ requires collection, embedding and index_name
+        init_args = {
+            "collection": collection,
+            "index_name": index_name,
+            "embedding": params.get("embedding"),
+        }
+
+        return class_object(**init_args)
+
+    if "texts" in params:
+        params["documents"] = params.pop("texts")
+
+    params["collection"] = collection
+    params["index_name"] = index_name
+
+    return class_object.from_documents(**params)
+
+
 def initialize_supabase(class_object: Type[SupabaseVectorStore], params: dict):
     """Initialize supabase and return the class object"""
     from supabase.client import Client, create_client
@@ -89,6 +123,12 @@ def initialize_pinecone(class_object: Type[Pinecone], params: dict):
     pinecone_api_key = params.get("pinecone_api_key")
     pinecone_env = params.get("pinecone_env")
 
+    if pinecone_api_key is None or pinecone_env is None:
+        if os.getenv("PINECONE_API_KEY") is not None:
+            pinecone_api_key = os.getenv("PINECONE_API_KEY")
+        if os.getenv("PINECONE_ENV") is not None:
+            pinecone_env = os.getenv("PINECONE_ENV")
+
     if pinecone_api_key is None or pinecone_env is None:
         raise ValueError(
             "Pinecone API key and environment must be provided in the params"

src/backend/langflow/template/frontend_node/vectorstores.py

@@ -7,6 +7,18 @@ from langflow.template.frontend_node.base import FrontendNode
 class VectorStoreFrontendNode(FrontendNode):
     def add_extra_fields(self) -> None:
         extra_fields: List[TemplateField] = []
+        # Add search_kwargs field
+        extra_field = TemplateField(
+            name="search_kwargs",
+            field_type="code",
+            required=False,
+            placeholder="",
+            show=True,
+            advanced=True,
+            multiline=False,
+            value="{}",
+        )
+        extra_fields.append(extra_field)
         if self.template.type_name == "Weaviate":
             extra_field = TemplateField(
                 name="weaviate_url",
@@ -134,6 +146,45 @@ class VectorStoreFrontendNode(FrontendNode):
             )
             extra_fields.extend((extra_field, extra_field2, extra_field3, extra_field4))
 
+        elif self.template.type_name == "MongoDBAtlasVectorSearch":
+            # add "mongodb_atlas_cluster_uri",
+            # "collection_name",
+            # "db_name",
+            extra_field = TemplateField(
+                name="mongodb_atlas_cluster_uri",
+                field_type="str",
+                required=False,
+                placeholder="",
+                show=True,
+                advanced=True,
+                multiline=False,
+                display_name="MongoDB Atlas Cluster URI",
+                value="",
+            )
+            extra_field2 = TemplateField(
+                name="collection_name",
+                field_type="str",
+                required=False,
+                placeholder="",
+                show=True,
+                advanced=True,
+                multiline=False,
+                display_name="Collection Name",
+                value="",
+            )
+            extra_field3 = TemplateField(
+                name="db_name",
+                field_type="str",
+                required=False,
+                placeholder="",
+                show=True,
+                advanced=True,
+                multiline=False,
+                display_name="Database Name",
+                value="",
+            )
+            extra_fields.extend((extra_field, extra_field2, extra_field3))
+
         if extra_fields:
             for field in extra_fields:
                 self.template.add_field(field)
@@ -160,6 +211,9 @@ class VectorStoreFrontendNode(FrontendNode):
             "query_name",
             "supabase_url",
             "supabase_service_key",
+            "mongodb_atlas_cluster_uri",
+            "collection_name",
+            "db_name",
         ]
         advanced_fields = [
             "n_dim",
@@ -179,10 +233,15 @@ class VectorStoreFrontendNode(FrontendNode):
             "pinecone_api_key",
             "pinecone_env",
             "client_kwargs",
+            "search_kwargs",
         ]
 
         # Check and set field attributes
         if field.name == "texts":
+            # if field.name is "texts" it has to be replaced
+            # when instantiating the vectorstores
+            field.name = "documents"
+
             field.field_type = "TextSplitter"
             field.display_name = "Documents"
             field.required = False