Express js Tutorial

Express js Introduction

Express.js is a web framework which is based on the core Node.js http module. It is a big strength of Node.js that makes the development significantly easier and much faster. It is an abstraction layer that stays on the top of the Node's built-in HTTP server.

It has added new features, it has huge collection of libraries and modules available through npm. It facilitates the rendering of dynamic HTML views that makes it easier to organize your application's functionality with middleware and routing.

When express.js application is running, it listens to the incoming requests. It processes the request according to the defined chain of middlewares and routes starting from top to bottom.

Features of Express.js

  • It is fast, unopinionated, minimalist web framework.
  • It adds a number of helpful conveniences to Node.js's HTTP server.
  • Express applications have middleware and routes, both complement one another.
  • The middleware makes easy to add custom support for sessions, cookies, security, compression, etc.
  • It maps URL for web server and breaks the request handler function into smaller pieces.
  • It also provides MVC like structures for your web applications.

How Express.js link to Node.js

The following diagram demonstrates how a request would flow through an express application.

Express.js Introduction