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Node.js and Modules require. Objects are not assigned by reference?

I'm writing this question after 2 days of total struggling during which I couldn't find a solution but also couldn't find an explanation of why this code is not working.
I will report a super simplified simulation of my code.
I have 5 Node.js files:
1) server.js -> Is the main file used to start the server
2) globalVars.js -> Is where all the server "global" objects are stored.
3) globalFunctions.js -> Is where all "general" functions are stored to be used by all other modules
4) helloManager.js -> Example file which contains some standard function used by the server
5) aspect.js -> Same as helloManager.js
//server.js
//Loading the globalVars file. All objects are passed by reference so I use this to store the global variables
var globalVars = require("./globalVars.js");
//Assigning to the respective global object all the functions exported from other modules
globalVars.Modules.globalFunctions = require("./globalFunctions.js");
globalVars.Modules.aspect = require("./aspect.js");
globalVars.Modules.helloManager = require("./helloManager.js");
//After this point, the objects in globalVars.js will be populated with the respective functions exported from the files
//A timeout just to be sure it is not a problem of timing? (Well, it is not...)
setTimeout(function(){
console.log(globalVars.Modules.helloManager.helloOutput());
}, 2000);
/*
Console will throw the following error:
../globalFunctions.js:6
return "MR. " + aspect.getAspect();
^
TypeError: aspect.getAspect is not a function
*/
//globalVars.js
//Objects that will be populated with the functions inside other modules
module.exports.Modules = {
aspect: {},
helloManager: {},
globalFunctions: {}
};
//helloManager.js
var globalVars = require("./globalVars.js");
var { globalFunctions } = globalVars.Modules;
module.exports.helloOutput = function(){
return "hello " + globalFunctions.getHumanData();
};
//aspect.js
module.exports.getAspect = function(){
return "human";
};
//globalFunctions.js
var globalVars = require("./globalVars.js");
var { aspect } = globalVars.Modules;
module.exports.getHumanData = function(){
return "MR. " + aspect.getAspect();
};
Please don't answer me to put everything in the same file, because my code is way more complicated to report so here I'm posting this very simple simulation.
I know that objects are assigned by reference and so if all modules get the variables from "globalVars" they works kinda like "global".
The problem is when in globalFunctions.js I load
var { aspect } = globalVars.Modules;
Since in server.js the module aspect.js is not loaded yet, it will be an empty object.
But I'm expecting that
var { aspect } = globalVars.Modules;
is getting the reference of globalVars and not a copy, so when server.js finishes loading all the modules, the variabile aspect inside globalVars.Modules will point to the correct object and so it would find the function I need!
Infact the console.log inside server.js is executed after all modules have been loaded for this exact reason.
Does anyone know what is the reason of this problem and how could I solve it?
Thank to everyone who will help!

What's happening
It's an issue of what it means to do const { aspect } = globalVars.Modules; (which is the same as const aspect = globalVars.Modules.aspect;). That is, it's a matter of assignment semantics.
Let's look at a simpler example, then we can see hot it applies to what you're doing. Assume you have:
let a = {/*original object*/};
When you do
b = a;
the value in a is copied into b. That value is an object reference, so they now both point to the same object, but there is no ongoing link between a and b. If you then do
a = {/*new object*/};
that has no effect whatsoever on b, because there's no ongoing link between a (the variable) and b (the variable). b still refers to the original object, not the new one.
The same is true of any assignable item, such as an object property or parameter. That's what's happening with globalVars.Modules.aspect. globalFunctions is grabbing the value (simple assignment semantics, though using destructuring), then server.js is replacing that value with a new one.
Here's how that's happening in your code:
// server.js
var globalVars = (function() {
// globalVars.js
return { // this is the `exports` object
Modules: {
aspect: {}, // *** That's the `a = {/*original object*/}`
}
};
})();
// back in server.js
globalVars.Modules.globalFunctions = (function() {
// globalFunctions.js
const { aspect } = globalVars.Modules; // **** That's the `b = a`
return { // this is the `exports` object
getHumanData: function(){
return "MR. " + aspect.getAspect();
}
};
})();
// back in server.js
globalVars.Modules.aspect = (function() { // *** that's the `a = {/*new object*/}
return { // this is the `exports` object
getAspect: function(){
return "human";
}
};
})();
// back in server.js
globalVars.Modules.globalFunctions.getHumanData(); // Fails because the object it's using
// is the old one, not the new one
How to fix it
globalFunctions.js relies on aspect.js, so have it rely on it directly:
// In `globalFunctions.js`
const aspect = require("./aspect.js");
module.exports.getHumanData = function(){
return "MR. " + aspect.getAspect();
};
Assuming there are no cycles, that'll work.
At a larger level: There may be no reason to have globalVars.Modules at all. A module is only loaded once (normally), so rather than globalVars.Modules, just have each module directly rely on the module it needs, rather than funnelling it all through a central object. Node.js' module cache is already the central object.
If you don't want globalFunctions.js to rely on aspect.js directly (why not?), then don't copy the aspect property from Modules, use it as of when you need it:
// In `globalFunctions.js`
const {Modules} = require("./globalVars.js");
module.exports.getHumanData = function(){
return "MR. " + Modules.aspect.getAspect();
};
That'll work assuming nothing reassigns Modules (which nothing seems to in the code you've shown). But again, it makes more sense to rely on aspect.js directly if you can.
It's kind of fun to note that this is one of the reasons that modern ESM modules don't use simple assignment semantics like CommonJS ones do. ESM wouldn't help your specific thing, because you're using your own globalVars.Modules object instead of using the module objects, but it solves a problem that people often had with CommonJS modules which, like your problem, was caused by expecting b (an imported value) to be affected when reassigning a (the exported value). The issue people would have with CommonJS happened mostly when there were cycles between two modules (circular dependencies, directly or indirectly). ESM solves this by making the imported binding (b in my example) a live binding to the exported binding (a in my example). This is the only place JavaScript has what you could argue is a form of pass-by-reference (references to variables).

As you've noticed, var { aspect } = globalVars.Modules; copies the current value of globalVars.Modules.aspect to the local variable aspect. It's just alternative syntax for var aspect = globalVars.Modules.aspect.
If you later change the value of globalVars.Modules.aspect to a new object (as opposed to mutating the object that is already there) then the local variable doesn't update.
If you want the most recent value then you need to continue accessing globalVars.Modules.aspect whenever you need it.

Unable to export variable from node js module

First of all I have checked all the questions on Stack Overflow regarding this.
I am trying to export variable str whose value is getting updated inside the function to another module but it is showing undefined after exporting it in another file.
But if I update the value of variable outside function then export is working fine.
I have a function with code in file Excel.js
var str='abc';
wb.xlsx.readFile(filePath).then(function()
{
var sh = wb.getWorksheet("Sheet1");
console.log("YOUR LECTURE IS",sh.getRow(goingSlot+1).getCell(DAY+1).value);
//console works fine
str="YOUR LECTURE IS"+sh.getRow(goingSlot+1).getCell(DAY+1).value;
//the assignment here leads to undefined after exporting
}
str="something";
//this successfully exports the value as something
And then I export this to my main file with syntax
exports.str=str;
Incase you need to see code for main file
The code for the main file is
const express=require('express');
const app=express();
const myle=require('./readingExcel.js');
const res=myle.name;
console.log(res);
//CONSOLE SHOWS UNDEFINED

exports.str and str are not the same variable even though you write exports.str = str
var a = 2;
var b = a;
a = 4;
console.log(b) // b is still 2 and not 4
So use exports.str directly instead of str.
exports.str = 'abc'
// ...
exports.str="YOUR LECTURE IS"+sh.getRow(goingSlot+1).getCell(DAY+1).value;
// ...
exports.str = 'something'

I just want to add something to #t.niese's response (which in my opinion is pretty solid).
Check your code for any mode.exports happening after your exports.str assignment. exports and module.exports are usually pointing to the same place, but I always use module.exports. Using exports has the risk of being overwritten somewhere else (module.exports too, but that is the real reference used by node).
https://medium.freecodecamp.org/node-js-module-exports-vs-exports-ec7e254d63ac

require("ssh2") without specific object in node.js

What does it mean if you require('ssh2') in Node.js without a specific object (e.g. require('ssh2').Client)? I have some code I am trying to understand and I am just learning Node.js. It's used like this:
var ssh2Connection = require("ssh2");
...
var conn new ssh2Connection();
conn.on("ready", function() {
...
});

Requiring require("ssh2") is essentially returning the value defined by this line
module.exports = 'hello'
Requiring require("ssh2").Client is essentially returning the value defined by this line
module.exports.Client = 'hello'
This is used to extend multiple objects to a module. Could be something like
module.exports.Client1 = 'hello1'
module.exports.Client2 = 'hello2'

interacting with javascript through the chrome console [duplicate]

This question already has answers here:
Console access to Javascript variables local to the $(document).ready function
(8 answers)
Closed 6 years ago.
I'm using a shopping cart api to build an ecommerce website. The creators made an sdk and then you have to make your own .js file for some other functions.
While debugging I would insert a console.log(etc..) anywhere in my .js file so that I could debug object options and etc..
But I would like to be able to use the sdk as a live tool, so instead of having to edit my .js file with new console.log() lines, I'd rather just be able to type object.color_code and have the console output that string for the object color code. At the moment though it just gives me uncaught reference error, object is not defined.
I think this is because my custom .js file has all of it's script inside a $(function() { EVERYTHING }); SO, when I try to call anything in EVERYTHING from the console it says it's undefined, but if I just used console.log inside EVERYTHING it would work. So is there a way I can get around this?
Feel free to explain why it isn't working but I'd like a way to enable this, don't tell me there isn't a way, even if I have to prefix what I want with the .js file it's coming from each time, I don't mind

You were correct in that all of your variables inside the function are only being defined locally, and thus can't be accessed via the console. However, in Javascript there are at least two options for setting global variables from inside functions; If you use these to declare a variable you want to access from outside the function, it will work:
Assign a value to an undeclared variable: varname=value;
Assign the variable to the window object: window.varname=value; or window['varname']=value;

A possible workaround is to expose the object(s) that you want to debug in the global scope:
(function() {
var privateStuff = { foo: 'bar' };
// make privateStuff public for debugging purposes
window['debugObject'] = privateStuff;
})();
document.write(debugObject.foo);
If you want to expose several objects with rather common names that are likely to collide with existing ones, make sure to expose them within an object with an uncommon name rather than directly:
(function() {
var x = { str: 'this is' },
y = { str: 'a test' };
window['debugObject'] = {
x: x,
y: y
};
})();
document.write(debugObject.x.str + ' ' + debugObject.y.str);

If you're happy to change the source file then you could export whatever you want to access from EVERYTHING as a global.
$(function() {
//EVERYTHING
...
window.Ireply = window.Ireply || {};
window.Ireply.object = object;
...
});
console.log(Ireply.object); // some object

You can change a declaration like
$(function(){
var cart = {};
})
To
var cart;
$(function(){
cart = {}
})
Or
$(function(){
var cart = {};
window.cart = cart;
})
But you will want to avoid polluting global namespace. You will also want to be careful about using globals inside callbacks or loops where you can run into unexpected behaviors since local variables scope is often important to be kept local

Object property is undefined

I don't know if I'm missing something here, but for some reason a configuration object I create is always undefined upon using:
gulpfile.config.js
var config = {
src_path: "Client/"
};
gulpfile.js
var config = require("./gulpfile.config.js");
gulp.task("test", function() {
util.log(config.src_path); // results in 'undefined'
});
Do objects have to be initialized within the scope of a gulp task or is there something wrong with the object declaration?

Add module.exports to your gulpfile.config.js, like so
# gulpfile.config.js
var config = {
src_path: "Client/"
};
module.exports = config
module.exports is the object that's returned as the result of a require call.

It does, indeed, look to me like you are redefining that variable, probably causing it to have the value true. Use the browser's JavaScript-console to be sure.