express-production

Express.js - Production Web Framework

Overview

Express is a minimal and flexible Node.js web application framework providing a robust set of features for web and mobile applications. This skill covers production-ready Express development including middleware architecture, structured error handling, security hardening, comprehensive testing, and deployment strategies.

Key Features:

• Flexible middleware architecture with composition patterns
• Centralized error handling with async support
• Security hardening (Helmet, CORS, rate limiting, input validation)
• Comprehensive testing with Supertest
• Production deployment with PM2 clustering
• Environment-based configuration
• Structured logging and monitoring
• Graceful shutdown patterns
• Zero-downtime deployments

Installation:

# Basic Express
npm install express

# Production stack
npm install express helmet cors express-rate-limit express-validator
npm install morgan winston compression
npm install dotenv

# Development tools
npm install -D nodemon supertest jest

# Optional: Database and auth
npm install mongoose jsonwebtoken bcrypt

When to Use This Skill

Use this comprehensive Express skill when:

• Building production REST APIs
• Creating microservices architectures
• Implementing secure web applications
• Need flexible middleware composition
• Require comprehensive error handling
• Building systems requiring extensive testing
• Deploying high-availability services
• Need granular control over request/response lifecycle

Express vs Other Frameworks:

• Express: Maximum flexibility, unopinionated, extensive ecosystem
• Fastify: Performance-focused, schema-based validation
• Koa: Modern async/await, minimalist
• NestJS: TypeScript-first, opinionated, enterprise patterns

Quick Start

Minimal Express Server

// server.js
const express = require('express');
const app = express();
const PORT = process.env.PORT || 3000;

// Middleware
app.use(express.json());
app.use(express.urlencoded({ extended: true }));

// Routes
app.get('/', (req, res) => {
  res.json({ message: 'Hello World' });
});

app.get('/health', (req, res) => {
  res.json({ status: 'ok', uptime: process.uptime() });
});

// Error handler
app.use((err, req, res, next) => {
  console.error(err.stack);
  res.status(500).json({ error: 'Internal server error' });
});

// Start server
const server = app.listen(PORT, () => {
  console.log(`Server running on port ${PORT}`);
});

// Graceful shutdown
process.on('SIGTERM', () => {
  console.log('SIGTERM received, closing server...');
  server.close(() => {
    console.log('Server closed');
    process.exit(0);
  });
});