express-typescript

import express, { Express } from 'express';
import helmet from 'helmet';
import cors from 'cors';
import { errorHandler } from './middleware/errorHandler';
import { requestLogger } from './middleware/requestLogger';
import routes from './routes';
 
const createApp = (): Express => {
  const app = express();
 
  // Security middleware
  app.use(helmet());
  app.use(cors());
 
  // Body parsing
  app.use(express.json());
  app.use(express.urlencoded({ extended: true }));
 
  // Request logging
  app.use(requestLogger);
 
  // Routes
  app.use('/api', routes);
 
  // Error handling (must be last)
  app.use(errorHandler);
 
  return app;
};
 
export default createApp;

import { Request, Response, NextFunction } from 'express';
 
// Request logging middleware
const requestLogger = (req: Request, res: Response, next: NextFunction): void => {
  const start = Date.now();
 
  res.on('finish', () => {
    const duration = Date.now() - start;
    console.log(`${req.method} ${req.path} ${res.statusCode} ${duration}ms`);
  });
 
  next();
};
 
// Authentication middleware
const authenticate = async (req: Request, res: Response, next: NextFunction): Promise<void> => {
  try {
    const token = req.headers.authorization?.split(' ')[1];
 
    if (!token) {
      res.status(401).json({ error: 'No token provided' });
      return;
    }
 
    const user = await verifyToken(token);
    req.user = user;
    next();
  } catch (error) {
    res.status(401).json({ error: 'Invalid token' });
  }
};

import { Router } from 'express';
import { authenticate } from '../middleware/auth';
import { validateRequest } from '../middleware/validateRequest';
import { createUserSchema, updateUserSchema } from './validators';
import * as controller from './controller';
 
const router = Router();
 
router.get('/', controller.listUsers);
router.get('/:id', controller.getUser);
router.post('/', validateRequest(createUserSchema), controller.createUser);
router.put('/:id', authenticate, validateRequest(updateUserSchema), controller.updateUser);
router.delete('/:id', authenticate, controller.deleteUser);
 
export default router;

import { z } from 'zod';
import { Request, Response, NextFunction } from 'express';
 
const createUserSchema = z.object({
  body: z.object({
    name: z.string().min(1),
    email: z.string().email(),
    password: z.string().min(8),
  }),
});
 
const validateRequest = (schema: z.ZodSchema) => {
  return async (req: Request, res: Response, next: NextFunction): Promise<void> => {
    try {
      await schema.parseAsync({
        body: req.body,
        query: req.query,
        params: req.params,
      });
      next();
    } catch (error) {
      if (error instanceof z.ZodError) {
        res.status(400).json({
          error: 'Validation failed',
          details: error.errors,
        });
        return;
      }
      next(error);
    }
  };
};

class AppError extends Error {
  constructor(
    public statusCode: number,
    public message: string,
    public code: string = 'INTERNAL_ERROR'
  ) {
    super(message);
    this.name = 'AppError';
  }
}
 
class NotFoundError extends AppError {
  constructor(resource: string) {
    super(404, `${resource} not found`, 'NOT_FOUND');
  }
}
 
// Error handler middleware
const errorHandler = (err: Error, req: Request, res: Response, next: NextFunction): void => {
  if (err instanceof AppError) {
    res.status(err.statusCode).json({
      error: err.code,
      message: err.message,
    });
    return;
  }
 
  console.error(err);
  res.status(500).json({
    error: 'INTERNAL_ERROR',
    message: 'An unexpected error occurred',
  });
};

// types/express.d.ts
import { User } from '../models/User';
 
declare global {
  namespace Express {
    interface Request {
      user?: User;
      requestId?: string;
    }
  }
}

import helmet from 'helmet';
import rateLimit from 'express-rate-limit';
 
app.use(helmet());
 
const limiter = rateLimit({
  windowMs: 15 * 60 * 1000, // 15 minutes
  max: 100, // limit each IP to 100 requests per windowMs
});
 
app.use('/api', limiter);

import request from 'supertest';
import createApp from '../app';
 
describe('Users API', () => {
  const app = createApp();
 
  it('should create a user', async () => {
    const response = await request(app)
      .post('/api/users')
      .send({ name: 'John', email: 'john@example.com', password: 'password123' })
      .expect(201);
 
    expect(response.body).toHaveProperty('id');
    expect(response.body.name).toBe('John');
  });
});