Alpha Vantage MCP Server

import { MongoClient, ObjectId, type Document } from "mongodb"; let globalClient: MongoClient | null = null; /** * Establishes connection to MongoDB using MONGODB_CONNECTION_STRING from environment * @returns The connected MongoClient instance * @throws Error if connection fails or MONGODB_CONNECTION_STRING is not defined */ export async function connect(): Promise<MongoClient> { let connectionString = process.env.MONGODB_CONNECTION_STRING; if (!connectionString) { throw new Error("MONGODB_CONNECTION_STRING environment variable is not defined"); } // Prefix connection string with mongodb:// if not already present if (!connectionString.startsWith("mongodb://") && !connectionString.startsWith("mongodb+srv://")) { connectionString = `mongodb://${connectionString}`; } try { const client = new MongoClient(connectionString); await client.connect(); globalClient = client; return client; } catch (error) { throw new Error(`Failed to connect to MongoDB: ${error instanceof Error ? error.message : String(error)}`); } } /** * Closes the MongoDB connection gracefully * @param client The MongoClient instance to disconnect */ export async function disconnect(client: MongoClient): Promise<void> { await client.close(); if (globalClient === client) { globalClient = null; } } /** * Lists all collection names in the specified database * @param db Database name * @returns Array of collection names */ export async function listCollections(db: string): Promise<string[]> { if (!globalClient) { throw new Error("Not connected to MongoDB. Call connect() first."); } const database = globalClient.db(db); const collections = await database.listCollections().toArray(); return collections.map(col => col.name); } /** * Creates a new collection in the specified database * @param db Database name * @param collection Collection name * @throws Error if collection already exists */ export async function createCollection(db: string, collection: string): Promise<void> { if (!globalClient) { throw new Error("Not connected to MongoDB. Call connect() first."); } const database = globalClient.db(db); const collections = await listCollections(db); if (collections.includes(collection)) { throw new Error(`Collection '${collection}' already exists in database '${db}'`); } await database.createCollection(collection); } /** * Drops/removes a collection from the specified database * @param db Database name * @param collection Collection name * @returns true if collection was dropped, false if collection didn't exist */ export async function removeCollection(db: string, collection: string): Promise<boolean> { if (!globalClient) { throw new Error("Not connected to MongoDB. Call connect() first."); } const database = globalClient.db(db); const collections = await listCollections(db); if (!collections.includes(collection)) { return false; } await database.collection(collection).drop(); return true; } /** * Retrieves all documents from a collection * @param db Database name * @param collection Collection name * @returns Array of documents */ export async function listDocuments<T extends Document = Document>(db: string, collection: string): Promise<T[]> { if (!globalClient) { throw new Error("Not connected to MongoDB. Call connect() first."); } const database = globalClient.db(db); const col = database.collection<T>(collection); return await col.find({}).toArray() as T[]; } /** * Queries documents matching the filter with optional sorting and limit * @param db Database name * @param collection Collection name * @param filter Query filter object * @param options Optional sort and limit parameters * @returns Array of matching documents */ export async function findDocuments<T = Document>( db: string, collection: string, filter: Record<string, any>, options?: { sort?: Record<string, 1 | -1>; limit?: number } ): Promise<T[]> { if (!globalClient) { throw new Error("Not connected to MongoDB. Call connect() first."); } const database = globalClient.db(db); const col = database.collection(collection); let cursor = col.find(filter); if (options?.sort) { cursor = cursor.sort(options.sort); } if (options?.limit) { cursor = cursor.limit(options.limit); } return await cursor.toArray() as T[]; } /** * Inserts a new document into the collection * @param db Database name * @param collection Collection name * @param doc Document to insert * @returns The inserted document's _id as a string */ export async function createDocument<T extends Document = Document>(db: string, collection: string, doc: T): Promise<string> { if (!globalClient) { throw new Error("Not connected to MongoDB. Call connect() first."); } const database = globalClient.db(db); const col = database.collection<T>(collection); const result = await col.insertOne(doc as any); return result.insertedId.toString(); } /** * Performs an incremental/partial update using MongoDB's $set operator * Only updates the fields provided in doc, preserving all other existing fields * @param db Database name * @param collection Collection name * @param id Document ID as string * @param doc Partial document with fields to update * @returns true if a document was modified, false otherwise */ export async function updateDocument<T extends Partial<Document> = Partial<Document>>( db: string, collection: string, id: string, doc: T ): Promise<boolean> { if (!globalClient) { throw new Error("Not connected to MongoDB. Call connect() first."); } const database = globalClient.db(db); const col = database.collection(collection); let objectId: ObjectId; try { objectId = new ObjectId(id); } catch (error) { throw new Error(`Invalid ObjectId: ${id}`); } const result = await col.updateOne( { _id: objectId }, { $set: doc } ); return result.modifiedCount > 0; } /** * Deletes a document by its _id * @param db Database name * @param collection Collection name * @param id Document ID as string * @returns true if a document was deleted, false if not found */ export async function deleteDocument(db: string, collection: string, id: string): Promise<boolean> { if (!globalClient) { throw new Error("Not connected to MongoDB. Call connect() first."); } const database = globalClient.db(db); const col = database.collection(collection); let objectId: ObjectId; try { objectId = new ObjectId(id); } catch (error) { throw new Error(`Invalid ObjectId: ${id}`); } const result = await col.deleteOne({ _id: objectId }); return result.deletedCount > 0; } /** * Upserts a document using replaceOne with upsert: true * If a document matching the filter exists, it will be replaced entirely with doc * If no document matches the filter, a new document will be inserted * @param db Database name * @param collection Collection name * @param filter Filter to match existing documents * @param doc Document to insert or replace with * @returns true if a document was inserted or replaced */ export async function upsertDocument<T = Document>( db: string, collection: string, filter: Record<string, any>, doc: T ): Promise<boolean> { if (!globalClient) { throw new Error("Not connected to MongoDB. Call connect() first."); } const database = globalClient.db(db); const col = database.collection(collection); const result = await col.replaceOne(filter, doc as any, { upsert: true }); return result.acknowledged; }