Nodejs sharing same initiated class to sub routes

I have a folder structer like this

.
├── models
│ └── System.js
└── src
├── app.js
├── index.js
└── routes
├── lemon
│ ├── auth
│ │ └── index.js
│ └── index.js
└── index.js


.

/models/System.js

class System
constructor()
this.test = null;



module.exports = System


.

/src/app.js

const express = require("express");
const _System = require("../models/System");

const app = express();

var System = new _System();
System.test = 1;

//..... other codes


.

/src/routes/lemon/auth/index.js

const express = require("express");
const _System = require("../../../../models/System");

const router = express.Router();

console.log(_System.test); //returns null

router.get('/', (req, res) =>
res.send("Hello World");
);

module.exports = router;


.

My folder structer is like this and I'm trying to share the System.test = 1 value defined at /app.js to /routes/lemon/auth/index.js.
But I couldn't able to do that and it always return null.

Is there anyway to share the same class init to sub routes?

PS: I know that my code isn't right and I've searched a lot. I can't understand English resources too much at the moment but I really searched up for it.

2 Answers
2

This doesnt work because System.js returns a class and not an instance or an object. So when var System = new _System(); System.test = 1; is exectued in app.js, the instance is local to the app module and not shared with the route.

System.js

var System = new _System(); System.test = 1;

app.js

If you want to share some kind of a config file between different modules, you can define your System module as a simple object:

System

'use strict' // <-- this is good practice to be more rigoreous

const System =
test: 1
;

module.exports = System;


Not the most elegant or scalable but;

global.System = new _System();


You can then use System anywhere.

System

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