Bugfix/closing mongodb connections (#2085)

* mongodb connection issue

* updating and pinning mongodb version

* removing pnpm-lock.yaml

* converting to a singleton

* Update pnpm lock file

* Downgrade mongodb

---------

Co-authored-by: vinodkiran <vinodkiran@usa.net>
Co-authored-by: Vinod Paidimarry <vinodkiran@outlook.in>

packages/components/nodes/memory/MongoDBMemory/MongoDBMemory.ts

@@ -1,5 +1,5 @@
 import { MongoClient, Collection, Document } from 'mongodb'
-import { MongoDBChatMessageHistory } from '@langchain/community/stores/message/mongodb'
+import { MongoDBChatMessageHistory } from '@langchain/mongodb'
 import { BufferMemory, BufferMemoryInput } from 'langchain/memory'
 import { mapStoredMessageToChatMessage, AIMessage, HumanMessage, BaseMessage } from '@langchain/core/messages'
 import { convertBaseMessagetoIMessage, getBaseClasses, getCredentialData, getCredentialParam } from '../../../src/utils'
@@ -10,7 +10,7 @@ let mongoUrl: string
 
 const getMongoClient = async (newMongoUrl: string) => {
     if (!mongoClientSingleton) {
-        // if client doesn't exists
+        // if client does not exist
         mongoClientSingleton = new MongoClient(newMongoUrl)
         mongoUrl = newMongoUrl
         return mongoClientSingleton

packages/components/nodes/vectorstores/MongoDBAtlas/MongoDBAtlas.ts

@@ -1,6 +1,6 @@
 import { flatten } from 'lodash'
 import { MongoClient } from 'mongodb'
-import { MongoDBAtlasVectorSearch } from '@langchain/community/vectorstores/mongodb_atlas'
+import { MongoDBAtlasVectorSearch } from '@langchain/mongodb'
 import { Embeddings } from '@langchain/core/embeddings'
 import { Document } from '@langchain/core/documents'
 import { ICommonObject, INode, INodeData, INodeOutputsValue, INodeParams } from '../../../src/Interface'
@@ -135,7 +135,8 @@ class MongoDBAtlas_VectorStores implements INode {
                 }
             }
 
-            const mongoClient = new MongoClient(mongoDBConnectUrl)
+            const mongoClient = await getMongoClient(mongoDBConnectUrl)
+            try {
                 const collection = mongoClient.db(databaseName).collection(collectionName)
 
                 if (!textKey || textKey === '') textKey = 'text'
@@ -147,8 +148,6 @@ class MongoDBAtlas_VectorStores implements INode {
                     textKey,
                     embeddingKey
                 })
-
-            try {
                 await mongoDBAtlasVectorSearch.addDocuments(finalDocs)
             } catch (e) {
                 throw new Error(e)
@@ -167,7 +166,8 @@ class MongoDBAtlas_VectorStores implements INode {
 
         let mongoDBConnectUrl = getCredentialParam('mongoDBConnectUrl', credentialData, nodeData)
 
-        const mongoClient = new MongoClient(mongoDBConnectUrl)
+        const mongoClient = await getMongoClient(mongoDBConnectUrl)
+        try {
             const collection = mongoClient.db(databaseName).collection(collectionName)
 
             if (!textKey || textKey === '') textKey = 'text'
@@ -181,7 +181,28 @@ class MongoDBAtlas_VectorStores implements INode {
             })
 
             return resolveVectorStoreOrRetriever(nodeData, vectorStore)
+        } catch (e) {
+            throw new Error(e)
+        }
     }
 }
 
+let mongoClientSingleton: MongoClient
+let mongoUrl: string
+
+const getMongoClient = async (newMongoUrl: string) => {
+    if (!mongoClientSingleton) {
+        // if client does not exist
+        mongoClientSingleton = new MongoClient(newMongoUrl)
+        mongoUrl = newMongoUrl
+        return mongoClientSingleton
+    } else if (mongoClientSingleton && newMongoUrl !== mongoUrl) {
+        // if client exists but url changed
+        mongoClientSingleton.close()
+        mongoClientSingleton = new MongoClient(newMongoUrl)
+        mongoUrl = newMongoUrl
+        return mongoClientSingleton
+    }
+    return mongoClientSingleton
+}
 module.exports = { nodeClass: MongoDBAtlas_VectorStores }

packages/components/package.json

@@ -39,6 +39,7 @@
         "@langchain/google-genai": "^0.0.10",
         "@langchain/groq": "^0.0.2",
         "@langchain/mistralai": "^0.0.11",
+        "@langchain/mongodb": "^0.0.1",
         "@langchain/openai": "^0.0.14",
         "@langchain/pinecone": "^0.0.3",
         "@mistralai/mistralai": "0.1.3",
@@ -81,7 +82,7 @@
         "lunary": "^0.6.16",
         "mammoth": "^1.5.1",
         "moment": "^2.29.3",
-        "mongodb": "6.2.0",
+        "mongodb": "6.3.0",
         "mysql2": "^3.9.2",
         "node-fetch": "^2.6.11",
         "node-html-markdown": "^1.3.0",