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name: nodejs-express-server description: > Build production-ready Express.js servers with middleware, authentication, routing, and database integration. Use when creating REST APIs, managing requests/responses, implementing middleware chains, and handling server logic.

Node.js Express Server

Table of Contents

• Overview
• When to Use
• Quick Start
• Reference Guides
• Best Practices

Overview

Create robust Express.js applications with proper routing, middleware chains, authentication mechanisms, and database integration following industry best practices.

When to Use

• Building REST APIs with Node.js
• Implementing server-side request handling
• Creating middleware chains for cross-cutting concerns
• Managing authentication and authorization
• Connecting to databases from Node.js
• Implementing error handling and logging

Quick Start

Minimal working example:

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("/health", (req, res) => {
  res.json({ status: "OK", timestamp: new Date().toISOString() });
});

// Error handling
app.use((err, req, res, next) => {
  console.error(err.stack);
  res.status(err.status || 500).json({
    error: err.message,
    requestId: req.id,
  });
});

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

Reference Guides

Detailed implementations in the references/ directory:

| Guide | Contents | |---|---| | Basic Express Setup | Basic Express Setup | | Middleware Chain Implementation | Middleware Chain Implementation | | Database Integration (PostgreSQL with Sequelize) | Database Integration (PostgreSQL with Sequelize) | | Authentication with JWT | Authentication with JWT | | RESTful Routes with CRUD Operations | RESTful Routes with CRUD Operations | | Error Handling Middleware | Error Handling Middleware | | Environment Configuration | Environment Configuration |

Best Practices

✅ DO

• Use middleware for cross-cutting concerns
• Implement proper error handling
• Validate input data before processing
• Use async/await for async operations
• Implement authentication on protected routes
• Use environment variables for configuration
• Add logging and monitoring
• Use HTTPS in production
• Implement rate limiting
• Keep route handlers focused and small

❌ DON'T

• Handle errors silently
• Store sensitive data in code
• Use synchronous operations in routes
• Forget to validate user input
• Implement authentication in route handlers
• Use callback hell (use promises/async-await)
• Expose stack traces in production
• Trust client-side validation only