Use ES6 Import in Node.js

Since ES6, JavaScript has a standardized way in terms of using the import statement in your project to include modules. Originally Node.js was using require() to import a module but with the update it is also imported ES6 import. This article will explain how to use ES6 import in Node.js, why it is important, and what constitutes good practice.

Why Use ES6 Imports in Node.js?

The following are some key reasons why you should use ES6 imports in Node.js ?

• Modern Syntax: import is even better than require() to import modules because it is clean and more efficient.
• Tree-Shaking: ES6 modules have the option to support tree-shaking, in which all the unused code is removed during the buildup
• Consistency: In terms of browser syntax with ES6, use of import makes your script consistent throughout the entire code.

How to Implement ES6 Import in Node.js?

We have listed here the important steps to implement ES6 import in Node.js ?

STEP 1: That Node.js supports ES6 Modules

From Node.js v 12, native support for ES6 modules is available with the.mjs extension or with type: module in package.json file.
Check your Node.js version:

node --version

STEP 2: Configure Your Project for ES6 Modules

Option 1: Use .mjs File Extension

To specify an ES6 module, make your file name have the.mjs extension.

Option 2: When creating the bundle, add "type": "module" in package.json

Update your package.json to include:

{
  "type": "module"
}

STEP 3: Use the import Syntax

Here's an example of using import to include a module:

// Import a named export
import { readFile } from 'fs/promises';

// Import the default export
import express from 'express';

const app = express();
console.log('Server is running...');

4. Handle CommonJS Compatibility

If you're working with older CommonJS modules, use the createRequire function to include them:

import { createRequire } from 'module';
const require = createRequire(import.meta.url);
const lodash = require('lodash');

5. Run the Script

Run your script using Node.js:

node index.mjs

Best Practices for Using ES6 Import in Node.js

We have listed some best practices advice for using ES6 import in Node.js.

• Avoid Mixing Import and Require: Whenever possible, stay with one style of the module system to make it easier for users to switch between them
• Use Absolute Imports: Configure module paths for cleaner code.
• Leverage Tree-Shaking: Import only what you need
• Upgrade Legacy Code: Gradually replace require() with import statement.

Common Errors and the Solutions

The following are some common errors along with their solutions ?

1. SyntaxError: Cannot use import statement outside a module

Ensure your file is .mjs or type is set to "module" in package.json.

2. Cannot Find Module

Use a relative or absolute path with import.

3. Mixed ESM and CommonJS Issues

Use createRequire for compatibility.

Conclusion

Node programs should operate in ES6 style imports to be in compliance with modern standards of JavaScript. It improves the readability, the performance and, as important, the maintainability of the code. Read the instructions in this guide and adopt the recommended practices in your Node.js apps to begin using ES6 import right now.