Question

I am a learner in Node.js.

1. What’s Express.js?
2. What’s the purpose of it with Node.js?
3. Why do we actually need Express.js? How is it useful for us to use with Node.js?
4. What’s Redis? Does it come with Express.js?

Answer 1

This is over simplifying it, but Express.js is to Node.js what Ruby on Rails or Sinatra is to Ruby.

Express 3.x is a light-weight web application framework to help organize your web application into an MVC architecture on the server side. You can use a variety of choices for your templating language (like EJS, Jade, and Dust.js).

You can then use a database like MongoDB with Mongoose (for modeling) to provide a backend for your Node.js application. Express.js basically helps you manage everything, from routes, to handling requests and views.

Redis is a key/value store — commonly used for sessions and caching in Node.js applications. You can do a lot more with it, but that’s what I’m using it for. I use MongoDB for more complex relationships, like line-item <-> order <-> user relationships. There are modules (most notably connect-redis) that will work with Express.js. You will need to install the Redis database on your server.

Here is a link to the Express 3.x guide: https://expressjs.com/en/3x/api.html