* adds complete tests for database

* adds healtCheck and connection status related methods DatabaseConnection class

src/__tests__/database.test.ts

@@ -1,6 +1,220 @@
-// test temporal para probar que jest funciona
+import mongoose from 'mongoose';
+import { DatabaseConnection } from '../config/database.js';
+import { Logger } from '../utils/logger.js';
+
+// Mock mongoose
+jest.mock('mongoose', () => {
+  const mockConnection = {
+    readyState: 0,
+    on: jest.fn(),
+    once: jest.fn()
+  };
+  
+  return {
+    connect: jest.fn(),
+    disconnect: jest.fn(),
+    connection: mockConnection
+  };
+});
+
+// Mock Logger
+jest.mock('../utils/logger.js', () => ({
+  Logger: {
+    database: {
+      connected: jest.fn(),
+      disconnected: jest.fn(),
+      reconnected: jest.fn(),
+      alreadyConnected: jest.fn(),
+      notConnected: jest.fn()
+    },
+    error: jest.fn()
+  }
+}));
+
+// Mock config
+jest.mock('../config/config.js', () => ({
+  config: {
+    mongodbUri: 'mongodb://localhost:27017/test'
+  }
+}));
+
 describe('DatabaseConnection', () => {
+  let mockMongoose: jest.Mocked<typeof mongoose>;
+  let mockLogger: jest.Mocked<typeof Logger>;
+  let databaseConnection: DatabaseConnection;
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+    mockMongoose = mongoose as jest.Mocked<typeof mongoose>;
+    mockLogger = Logger as jest.Mocked<typeof Logger>;
+    
+    // Reset singleton instance
+    (DatabaseConnection as any).instance = null;
+    databaseConnection = DatabaseConnection.getInstance();
+  });
+
   describe('Singleton Pattern', () => {
-        test('should return the same instance', () => {})
+    test('should return the same instance', () => {
-    })
+      const instance1 = DatabaseConnection.getInstance();
-})
+      const instance2 = DatabaseConnection.getInstance();
+      expect(instance1).toBe(instance2);
+    });
+  });
+
+  describe('connect', () => {
+    test('should connect to MongoDB successfully', async () => {
+      mockMongoose.connect.mockResolvedValueOnce(mockMongoose);
+      Object.defineProperty(mockMongoose.connection, 'readyState', { value: 1, writable: true });
+
+      await databaseConnection.connect();
+
+      expect(mockMongoose.connect).toHaveBeenCalledWith('mongodb://localhost:27017/test', {
+        maxPoolSize: 10,
+        serverSelectionTimeoutMS: 5000,
+        socketTimeoutMS: 45000,
+        bufferCommands: false
+      });
+      expect(mockLogger.database.connected).toHaveBeenCalled();
+    });
+
+    test('should not connect if already connected', async () => {
+      // Set as already connected
+      (databaseConnection as any).isConnected = true;
+
+      await databaseConnection.connect();
+
+      expect(mockMongoose.connect).not.toHaveBeenCalled();
+      expect(mockLogger.database.alreadyConnected).toHaveBeenCalled();
+    });
+
+    test('should handle connection errors', async () => {
+      const error = new Error('Connection failed');
+      mockMongoose.connect.mockRejectedValueOnce(error);
+
+      await expect(databaseConnection.connect()).rejects.toThrow('Connection failed');
+      expect(mockLogger.error).toHaveBeenCalledWith('Failed to connect to MongoDB', { error });
+    });
+
+    test('should set up connection event listeners', async () => {
+      mockMongoose.connect.mockResolvedValueOnce(mockMongoose);
+      Object.defineProperty(mockMongoose.connection, 'readyState', { value: 1, writable: true });
+
+      await databaseConnection.connect();
+
+      expect(mockMongoose.connection.on).toHaveBeenCalledWith('error', expect.any(Function));
+      expect(mockMongoose.connection.on).toHaveBeenCalledWith('disconnected', expect.any(Function));
+      expect(mockMongoose.connection.on).toHaveBeenCalledWith('reconnected', expect.any(Function));
+    });
+  });
+
+  describe('disconnect', () => {
+    test('should disconnect from MongoDB successfully', async () => {
+      // Set as connected
+      (databaseConnection as any).isConnected = true;
+      mockMongoose.disconnect.mockResolvedValueOnce(undefined);
+
+      await databaseConnection.disconnect();
+
+      expect(mockMongoose.disconnect).toHaveBeenCalled();
+      expect(mockLogger.database.disconnected).toHaveBeenCalled();
+      expect((databaseConnection as any).isConnected).toBe(false);
+    });
+
+    test('should not disconnect if not connected', async () => {
+      // Set as not connected
+      (databaseConnection as any).isConnected = false;
+
+      await databaseConnection.disconnect();
+
+      expect(mockMongoose.disconnect).not.toHaveBeenCalled();
+      expect(mockLogger.database.notConnected).toHaveBeenCalled();
+    });
+
+    test('should handle disconnection errors', async () => {
+      const error = new Error('Disconnection failed');
+      (databaseConnection as any).isConnected = true;
+      mockMongoose.disconnect.mockRejectedValueOnce(error);
+
+      await expect(databaseConnection.disconnect()).rejects.toThrow('Disconnection failed');
+      expect(mockLogger.error).toHaveBeenCalledWith('Error disconnecting from MongoDB', { error });
+    });
+  });
+
+  describe('isConnected', () => {
+    test('should return true when connected', () => {
+      (databaseConnection as any).isConnected = true;
+      expect(databaseConnection.getConnectionStatus()).toBe(true);
+    });
+
+    test('should return false when not connected', () => {
+      (databaseConnection as any).isConnected = false;
+      expect(databaseConnection.getConnectionStatus()).toBe(false);
+    });
+  });
+
+  describe('Event Handlers', () => {
+    test('should handle connection error event', async () => {
+      mockMongoose.connect.mockResolvedValueOnce(mockMongoose);
+      Object.defineProperty(mockMongoose.connection, 'readyState', { value: 1, writable: true });
+      
+      let errorHandler: Function;
+      (mockMongoose.connection.on as jest.Mock).mockImplementation((event, handler) => {
+        if (event === 'error') {
+          errorHandler = handler;
+        }
+        return mockMongoose.connection;
+      });
+
+      await databaseConnection.connect();
+
+      // Simulate error event
+      const testError = new Error('Connection error');
+      errorHandler!(testError);
+
+      expect(mockLogger.error).toHaveBeenCalledWith('MongoDB connection error', { error: testError });
+      expect((databaseConnection as any).isConnected).toBe(false);
+    });
+
+    test('should handle disconnected event', async () => {
+      mockMongoose.connect.mockResolvedValueOnce(mockMongoose);
+      Object.defineProperty(mockMongoose.connection, 'readyState', { value: 1, writable: true });
+      
+      let disconnectedHandler: Function;
+      (mockMongoose.connection.on as jest.Mock).mockImplementation((event, handler) => {
+        if (event === 'disconnected') {
+          disconnectedHandler = handler;
+        }
+        return mockMongoose.connection;
+      });
+
+      await databaseConnection.connect();
+
+      // Simulate disconnected event
+      disconnectedHandler!();
+
+      expect(mockLogger.database.disconnected).toHaveBeenCalled();
+      expect((databaseConnection as any).isConnected).toBe(false);
+    });
+
+    test('should handle reconnected event', async () => {
+      mockMongoose.connect.mockResolvedValueOnce(mockMongoose);
+      Object.defineProperty(mockMongoose.connection, 'readyState', { value: 1, writable: true });
+      
+      let reconnectedHandler: Function;
+      (mockMongoose.connection.on as jest.Mock).mockImplementation((event, handler) => {
+        if (event === 'reconnected') {
+          reconnectedHandler = handler;
+        }
+        return mockMongoose.connection;
+      });
+
+      await databaseConnection.connect();
+
+      // Simulate reconnected event
+      reconnectedHandler!();
+
+      expect(mockLogger.database.reconnected).toHaveBeenCalled();
+      expect((databaseConnection as any).isConnected).toBe(true);
+    });
+  });
+});

src/config/database.ts

@@ -1,9 +1,10 @@
 import mongoose from 'mongoose';
-import config from './config'
+import { config } from '../config/config.js';
+import { Logger } from '../utils/logger.js';
 
 export class DatabaseConnection {
   private static instance: DatabaseConnection;
-    private isConnected: boolean = false; // a implementar
+  private isConnected: boolean = false;
 
   private constructor() {}
 
@@ -16,7 +17,7 @@ export class DatabaseConnection {
 
   public async connect(): Promise<void> {
     if (this.isConnected) {
-        console.log("database is already connected")
+      Logger.database.alreadyConnected();
       return;
     }
 
@@ -29,27 +30,66 @@ export class DatabaseConnection {
       });
 
       this.isConnected = true;
-        console.log("database connected")
+      Logger.database.connected();
 
       mongoose.connection.on('error', (error) => {
-          console.log('MongoDB connection error', { error });
+        Logger.error('MongoDB connection error', { error });
         this.isConnected = false;
       });
 
       mongoose.connection.on('disconnected', () => {
-          console.log('MongoDB connection disconnected');
+        Logger.database.disconnected();
         this.isConnected = false;
       });
 
       mongoose.connection.on('reconnected', () => {
-          console.log('MongoDB connection reconnected');
+        Logger.database.reconnected();
         this.isConnected = true;
       });
 
     } catch (error) {
-        console.log('MongoDB Failed to connect', { error });
+      Logger.error('Failed to connect to MongoDB', { error });
       this.isConnected = false;
       throw error;
     }
   }
+
+  public async disconnect(): Promise<void> {
+    if (!this.isConnected) {
+      Logger.database.notConnected();
+      return;
     }
+
+    try {
+      await mongoose.disconnect();
+      this.isConnected = false;
+      Logger.database.disconnected();
+    } catch (error) {
+      Logger.error('Error disconnecting from MongoDB', { error });
+      throw error;
+    }
+  }
+
+  public getConnectionStatus(): boolean {
+    return this.isConnected && mongoose.connection.readyState === 1;
+  }
+
+  public async healthCheck(): Promise<{ status: string; message: string }> {
+    try {
+      if (!this.isConnected) {
+        return { status: 'error', message: 'Database not connected' };
+      }
+
+      await mongoose.connection.db?.admin().ping();
+      return { status: 'ok', message: 'Database connection is healthy' };
+    } catch (error) {
+      return { 
+        status: 'error', 
+        message: `Database health check failed: ${error instanceof Error ? error.message : 'Unknown error'}` 
+      };
+    }
+  }
+}
+
+export const database = DatabaseConnection.getInstance();
+export default database;