Enable Filters in MongoDB Vector Search Retriever (#3333)

* added: support to metadata filter using mongodb vector search retriever

* fix: format lint

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

@@ -86,6 +86,13 @@ class MongoDBAtlas_VectorStores implements INode {
                 additionalParams: true,
                 optional: true
             },
+            {
+                label: 'Mongodb Metadata Filter',
+                name: 'mongoMetadataFilter',
+                type: 'json',
+                optional: true,
+                additionalParams: true
+            },
             {
                 label: 'Top K',
                 name: 'topK',
@@ -164,9 +171,12 @@ class MongoDBAtlas_VectorStores implements INode {
         let textKey = nodeData.inputs?.textKey as string
         let embeddingKey = nodeData.inputs?.embeddingKey as string
         const embeddings = nodeData.inputs?.embeddings as Embeddings
+        const mongoMetadataFilter = nodeData.inputs?.mongoMetadataFilter as object
 
         let mongoDBConnectUrl = getCredentialParam('mongoDBConnectUrl', credentialData, nodeData)
 
+        const filter: MongoDBAtlasVectorSearch['FilterType'] = {}
+
         const mongoClient = await getMongoClient(mongoDBConnectUrl)
         try {
             const collection = mongoClient.db(databaseName).collection(collectionName)
@@ -181,7 +191,20 @@ class MongoDBAtlas_VectorStores implements INode {
                 embeddingKey
             }) as unknown as VectorStore
 
-            return resolveVectorStoreOrRetriever(nodeData, vectorStore)
+            if (mongoMetadataFilter) {
+                const metadataFilter = typeof mongoMetadataFilter === 'object' ? mongoMetadataFilter : JSON.parse(mongoMetadataFilter)
+
+                for (const key in metadataFilter) {
+                    filter.preFilter = {
+                        ...filter.preFilter,
+                        [key]: {
+                            $eq: metadataFilter[key]
+                        }
+                    }
+                }
+            }
+
+            return resolveVectorStoreOrRetriever(nodeData, vectorStore, filter)
         } catch (e) {
             throw new Error(e)
         }