If you're encountering the "Must use import to load ES Module" error while trying to import modules in your Node.js project, don't worry! This issue often occurs when working with ES Modules in Node.js, but it's straightforward to resolve. In this guide, we'll walk you through the steps to fix this error and successfully import modules in your Node.js application.
When you see the "Must use import to load ES Module" error, it means that Node.js is expecting you to use an ES module import statement to load a module but instead encountering a different syntax or approach that's incompatible with ES Modules.
To resolve this error, the first thing you need to do is ensure that your code is using ES module syntax for importing modules. In ES Modules, you should use the `import` statement to bring in modules, rather than the traditional `require` method used for CommonJS modules.
Here's an example of how you should import modules in Node.js using ES Modules syntax:
import fs from 'fs';By following this syntax, you can avoid the "Must use import to load ES Module" error and correctly import modules in your Node.js application.
Another common reason for this error is when you have both ES Modules and CommonJS modules in the same file or project. To prevent conflicts between the two module systems, you need to make sure that your entire project is consistently using either ES Modules or CommonJS modules.
If you need to mix ES Modules and CommonJS modules in the same project, you can use the `.mjs` extension for ES Modules files and the `.js` extension for CommonJS files. This helps Node.js distinguish between the two types of modules and prevents the "Must use import to load ES Module" error.
Additionally, if you're working with ES Modules in Node.js, ensure that you're using a version of Node.js that supports ES Modules. Starting from Node.js version 12, ES Modules are supported natively, but you may need to specify the `type: "module"` field in your `package.json` to enable ES module support in your project.
To do this, add the following line to your `package.json` file:
"type": "module"By including this line in your `package.json`, you inform Node.js that your project uses ES Modules, allowing you to import modules without encountering the "Must use import to load ES Module" error.
In summary, when facing the "Must use import to load ES Module" error in Node.js, remember to use the correct ES Modules syntax with the `import` statement, ensure consistency in module systems throughout your project, and specify ES module support in your `package.json` if needed. By following these steps, you can resolve the error and import modules successfully in your Node.js application.