I can't update node-fetch because of import, I'm only used with require

[Madriix]

debian@ns30:~/node/<projet>/server$ npm outdated
Package     Current  Wanted  Latest  Location                 Depended by
node-fetch    2.6.7   2.6.7   3.2.6  node_modules/node-fetch  server

Hi
I would like to update node-fetch but I don't know how to deal with this "import" thing, I usually only use "require".
Could someone teach me how to use both import and require?
The "imports" seem complicated to set up, I've never done

[jimmywarting]

it's possible to use node-fetch@3 in commonjs using async import
there are couple of ways to go around it, #1279 have a guide of how to solve it.

alternative could just be to update to NodeJS itself to v18 and use the new built fetch api built in into nodejs core.

[Madriix]

"type": "module" I added this in package.json and I put this import fetch from 'node-fetch'; in a javascript file, in the same as the old node-fetch. I get this error:

debian@ns30:~/node/<projet>/client$ cd /home/debian/node/<projet>/client && npm run prod

> client@2.1.7 prod
> grunt clean && grunt && grunt obf && pm2 stop <projet>_client  && pm2 start <projet>_client

Loading "Gruntfile.js" tasks...ERROR
>> Error [ERR_REQUIRE_ESM]: require() of ES Module /home/debian/node/<projet>/client/Gruntfile.js from /home/debian/node/<projet>/client/node_modules/grunt/lib/grunt/task.js not supported.
>> Gruntfile.js is treated as an ES module file as it is a .js file whose nearest parent package.json contains "type": "module" which declares all .js files in that package scope as ES modules.
>> Instead rename Gruntfile.js to end in .cjs, change the requiring code to use dynamic import() which is available in all CommonJS modules, or change "type": "module" to "type": "commonjs" in /home/debian/node/<projet>/client/package.json to treat all .js files as CommonJS (using .mjs for all ES modules instead).
Warning: Task "clean" not found. Use --force to continue.

Aborted due to warnings.
debian@ns30:~/node/<projet>/client$

I don't understand, where could the problem come from?
There is no way to make "import" and "require" work in the same project?

[LinusU]

The error message seems to indicate that renaming your Gruntfile.js to Gruntfile.cjs, that way your grunt file will stay as an CommonJS file whereas the rest of your project will use the "type": "module" that you added.

If you want to mix you can use .cjs and .mjs as the file extension to use CommonJS and ESM respectively...

[Madriix]

On a simple project of test with a single server.js file, the import works very well :

import fetch from 'node-fetch'

const address = "<ipv4>";


const params = new URLSearchParams();
params.append('ip', address);

fetch("https://site/ips.php", { method: 'POST', body: params })
.then((res) => {
    /*ip = res.ip;
    host = res.host;*/
    return res.json()
})
.then((json) => {
   console.log("ip: %s", json.ip);
}).catch((err) => {
    console.error(err);
});

But the problem is on a big project, there are several .js files and in almost every .js file there are require("") including a node-fetch 3 import, it's quite incomprehensible to migrate, here is the map of my project:

Projet/config.js
Projet/client/Grunfiles.cjs (grunt)
Projet/client/libs/cachebuster.cjs (grunt)
Projet/client/modals/index.cjs
Projet/client/modals/templates/<files .html>
Projet/client/router/db.cjs
Projet/client/router/default.cjs This is the only file that has a node-fetch import and there are other require()
Projet/client/server.cjs  (with @hapi/hapi)
Projet/client/<others files not .js>
Projet/server/<files> (here is another folder for another node-fetch (a second one, skipped for now, i want to learn how to solve for client))

grunt clean && grunt they work but not "node server.cjs" the error returned is this:

G:\node\Projet\client>node server.cjs
Test1: Configuring Hapi server...
Registering plugins...
Test2: Configuring Hapi server...
Registering plugins...
Plugins registered; adding views...
Views added; adding routes...
No routes found: G:\node\Projet\client\router\routes\db.cjs
Failed to register routes.
Plugins registered; adding views...
Views added; adding routes...
No routes found: G:\node\Projet\client\router\routes\db.cjs
Failed to register routes.
Erreur: SyntaxError: Cannot use import statement outside a module

the error could come from here because it is the last modified file:
Projet/client/router/default.js
Here is its content:

/*
  This is the route loader.
  NOTE: This could possibly be done async,
        for now it works as needed.
*/
var fs = require('fs'),
    path = require('path');

module.exports = (function(routes){
     var rpath = path.resolve(__dirname, 'routes');
     fs.readdirSync(rpath).forEach(function(file) {
         if ((file = path.resolve(rpath, file))) {
            var load;
            if (!!(load = require(file)).length) {
               routes = routes.concat(load);
             } else {
               console.warn('No routes found: %s', file);
            }
         }
     });
     return routes;
})([]);

Where could the problem come from?
I spent all night on this without success, I prefer to ask here

[LinusU]

If you are not ready to upgrade to ESM, maybe it's better to stick with node-fetch v2.x which is our CommonJS release line