- Express.js Basics
- Express.js HOME
- Express.js Introduction
- Express.js Installation
- Express.js Basic App
- Express.js Routing
- Basics Routing
- Route Parameters
- Handling Query Strings
- Router Middleware
- Middleware
- What is Middleware?
- Application-Level Middleware
- Router-Level Middleware
- Built-In Middleware
- Error-Handling Middleware
- Third-Party Middleware
- Express.js HTTP
- Handling GET Requests
- Handling POST Requests
- Handling PUT Requests
- Handling DELETE Requests
- Templating Engines
- Using Templating Engines
- Setting Up EJS
- Setting Up Handlebars
- Setting Up Pug
- Request/Response
- Request Object
- Response Object
- Handling JSON Data
- Handling Form Data
- Static Files
- Serving Static Files
- Setting Up Static Folders
- Managing Assets
- Express.js Advanced
- Middleware Stack
- CORS in Express.js
- JWT Authentication
- Session Handling
- File Uploads
- Error Handling
- Databases
- Express.js with MongoDB
- MongoDB CRUD Operations
- Express.js with MySQL
- MySQL CRUD Operations
- Deployment
- Deploying Express.js Apps to Heroku
- Deploying Express.js Apps to AWS
- Deploying Express.js Apps to Vercel
Express.js Home
Express.js is a minimal and flexible Node.js web application framework that provides a robust set of features for building web and mobile applications. It is one of the most popular frameworks in the Node.js ecosystem, widely used for its simplicity and extensive middleware support.
Key Features of Express.js
Routing
- Express allows easy creation of routes to handle HTTP requests, enabling precise control over different URL endpoints and HTTP methods (GET, POST, PUT, DELETE, etc.).
Middleware Support
- Express supports middleware, which allows for the execution of code during the request-response cycle. This can include logging, authentication, error handling, or data parsing.
Template Engines
- Express allows the use of template engines like EJS, Pug, and Handlebars to generate dynamic HTML content, making it suitable for server-side rendering.
Error Handling
- Express provides built-in error handling, enabling developers to catch and handle errors in a consistent manner throughout the application.
Serving Static Files
- Express can easily serve static files, such as images, CSS, and JavaScript, which are commonly used in web applications.
RESTful API Creation
- Express is commonly used to build RESTful APIs that allow seamless communication between the client and the server.
Extensive Plugin Ecosystem
- Express has a large ecosystem of plugins and middleware available through npm, enabling developers to extend its functionality.
Getting Started with Express.js
Installation
- Express can be easily installed via npm (Node Package Manager) by running the following command:
npm install express
Creating a Simple Express App
- A basic Express application can be set up with just a few lines of code. Here’s an example:
const express = require('express');
const app = express();
app.get('/', (req, res) => {
res.send('Hello, Express!');
});
app.listen(3000, () => {
console.log('Server is running on port 3000');
});
- This creates a simple server that responds with "Hello, Express!" when you visit the root URL.
Setting Up Middleware
- Middleware in Express can be added globally or for specific routes. Here’s an example of using middleware for logging:
app.use((req, res, next) => {
console.log(`${req.method} ${req.url}`);
next(); // Call the next middleware function
});
Summary
Express.js is a powerful and easy-to-use framework that simplifies web development in Node.js. With its minimalist structure, middleware support, and routing capabilities, Express provides a flexible foundation for building scalable applications and APIs. It remains one of the most popular frameworks for Node.js developers, offering a simple yet robust approach to server-side development.