How to dynamically create and and call a function at runtime in NodeJs

Question

This is how I dynamically add a function to the window object at run-time:

(function (myPluginModuleLib, $, undefined) {
    myPluginModuleLib.myModuleMethod =  (varArgs) => {
        console.log('Dynamic Call :  ' + varArgs);
    };
}(window.myPluginModuleLib = window.myPluginModuleLib || {}, jQuery));

Then I can globally call it at any time :

window.myPluginModuleLib.myModuleMethod('HELLO WORLD PARAMS!');

Is there a similar way to do this in NodeJs? I would like to add a function into memory. For exaple, in the main app.js, so that I could call it on demand, instead of always constructing it from a String:

let myModuleMethodString = 'var myModuleMethod = (varArgs) => { console.log("Dynamic Call : " + varArgs) }';
myModuleMethodString = myModuleMethodString.slice(myModuleMethodString.indexOf("{") + 1, myModuleMethodString.lastIndexOf("}"));

let myModuleMethod = new Function("varArgs", 'console.log("Dynamic Call : " + varArgs)');

try {
    myModuleMethod('HELLO WORLD PARAMS!');
} catch (error) {
    console.log(error);
}

Thank you all in advance.

Why do you think you can't do it similar to how you do it in the browser? It's still JavaScript.... — James
– James, Commented Oct 4, 2020 at 7:44
In the browser I attach it to the window object. How do I do that in Node, server side? — Program-Me-Rev
– Program-Me-Rev, Commented Oct 4, 2020 at 7:45
@Program-Me-Rev, you cannot attach to window which is running in your browser (client) from Node.js code running on your server. It has to be done on the client code. — cyrille
– cyrille, Commented Oct 4, 2020 at 7:59

Attila Reterics · Accepted Answer · 2020-10-04 08:13:23Z

1

If you want to stay with this solution, then you can use the global namespace in Node JS, what is similar to the window in the browsers, although it is not suggested to use globals.

Example:

global.myPluginModuleLib = {
    myModuleMethod : (varArgs) => {
        console.log('Dynamic Call :  ' + varArgs);
    }
};
global.myPluginModuleLib.myModuleMethod('HELLO WORLD PARAMS!');

answered Oct 4, 2020 at 8:13

Attila Reterics

262 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Kamil Janowski · Accepted Answer · 2020-10-04 08:14:09Z

1

short answer: you can just use "global" instead of "window". More info here: https://stackabuse.com/using-global-variables-in-node-js/

Long answer: this is not something you should ever do in Node.js. This just pollutes the global context. All your functions should always be defined within the context of a specific module

answered Oct 4, 2020 at 8:14

Kamil Janowski

2,0652 gold badges24 silver badges48 bronze badges

Collectives™ on Stack Overflow

How to dynamically create and and call a function at runtime in NodeJs

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related