fixing up db's and data-service

libs/mongodb-client/src/singleton.ts

@@ -0,0 +1,62 @@
+import { MongoDBClient } from './client';
+import type { MongoDBClientConfig } from './types';
+import type { Db } from 'mongodb';
+
+/**
+ * Singleton MongoDB client instance
+ * Provides global access to a single MongoDB connection
+ */
+let instance: MongoDBClient | null = null;
+
+/**
+ * Initialize the singleton MongoDB client
+ */
+export async function connectMongoDB(config?: MongoDBClientConfig): Promise<MongoDBClient> {
+  if (!instance) {
+    if (!config) {
+      throw new Error('MongoDB client not initialized. Call connectMongoDB(config) first.');
+    }
+    instance = new MongoDBClient(config);
+    await instance.connect();
+  }
+  return instance;
+}
+
+/**
+ * Get the singleton MongoDB client instance
+ * @throws Error if not initialized
+ */
+export function getMongoDBClient(): MongoDBClient {
+  if (!instance) {
+    throw new Error('MongoDB client not initialized. Call connectMongoDB(config) first.');
+  }
+  return instance;
+}
+
+/**
+ * Get the MongoDB database instance
+ * @throws Error if not initialized
+ */
+export function getDatabase(): Db {
+  if (!instance) {
+    throw new Error('MongoDB client not initialized. Call connectMongoDB(config) first.');
+  }
+  return instance.getDatabase();
+}
+
+/**
+ * Check if the MongoDB client is initialized
+ */
+export function isInitialized(): boolean {
+  return instance !== null && instance.connected;
+}
+
+/**
+ * Disconnect and reset the singleton instance
+ */
+export async function disconnectMongoDB(): Promise<void> {
+  if (instance) {
+    await instance.disconnect();
+    instance = null;
+  }
+}