Express.js is a popular web application framework used for building server-side applications with Node.js. It provides a simple and efficient way to handle HTTP requests and build APIs. Immer, on the other hand, is a powerful JavaScript library that allows you to work with immutable data structures in a more convenient and intuitive way.

In this blog post, we will explore how to integrate Immer into an Express.js project, enabling us to write cleaner code and simplify the handling of state changes.

Installation

To get started, make sure you have Node.js and npm installed on your machine. You can create a new Express.js project using the following command:

$ npm init express-app my-app

Once the project is created, install Immer by running the following command in your project directory:

$ npm install immer

Integrating Immer into Express.js

To integrate Immer into your Express.js project, you need to make a few modifications to your existing code.

Step 1: Import Immer

First, import Immer at the top of your server file:

const immer = require('immer');

Step 2: Use Immer in your Route Handlers

Once Immer is imported, you can use its powerful features within your route handlers. Immer’s produce function allows you to create a draft copy of your state, make changes to it in an immutable manner, and then produce a new immutable state object.

Here’s an example of how to use Immer within an Express.js route handler:

app.get('/api/users', (req, res) => {
  // Original state
  const users = [
    { id: 1, name: 'John Doe', email: 'john@example.com' },
    { id: 2, name: 'Jane Smith', email: 'jane@example.com' },
  ];

  // Produce a new state with Immer
  const newUsersState = immer.produce(users, (draftState) => {
    draftState.push({ id: 3, name: 'James Brown', email: 'james@example.com' });
  });

  res.json(newUsersState);
});

In the above example, we’re adding a new user to the existing array of users. By using Immer’s produce function, we ensure that the original state remains unchanged, and a new immutable state is created.

Step 3: Implement Immer in other parts of your project

You can follow a similar approach to integrate Immer into other parts of your Express.js project. Whether it’s handling state changes in middleware, controllers, or other route handlers, Immer can simplify the process of working with immutable data.

Conclusion

By integrating Immer into your Express.js project, you can take advantage of its powerful features for working with immutable data structures. This helps write cleaner and more maintainable code, making it easier to handle state changes in your server-side applications.

Try using Immer in your Express.js project and experience the benefits of working with immutable data structures. Share your thoughts and experiences on social media using the hashtags #Immer and #ExpressJS!

Happy coding!