CODEWITHSUNDEEP
javascriptnode.jsnode-modules
madu
madu

Reputation: 5450

Exporting multiple functions with arguments

All I am trying to do is to export two functions from a module. One function taking an argument and the other with no argument:

function initClass(params)
{
   return new Promise( (resolve, reject) => {
        if (!wallet) {
            wallet = new WalletClient(params);
            resolve(wallet);
        } else {
            console.log('Wallet is initialized');
            resolve(wallet);
        }
});
}

function getInstance()
{
   return wallet;
}

For initClass(params) only, I can do this as:

module.exports = (params) => {
   initClass(params)
}

And then I call this as:

var init = require('./class.js')(params).initClass(params);

This works fine.

Now, for me to export getInstance() as well, I have tried to do the following but it doesn't seem to work.

module.exports = (params) => {
   initClass(params),
   getInstance
}

This complaints that there is no function getInstance.

Then I tried this:

module.exports.init = (params) => {
   initClass(params)
}

module.exports.instance = {
   getInstance
}

Then call them as:

var init = require('./class.js').init(params).initClass(params);

What is the proper way to export multiple functions like this? Thank you.

Upvotes: 2

Views: 8523

Answers (3)

anuragb26
anuragb26

Reputation: 1475

module.exports is basically an object with keys which can refer to any variables/functions of your file.In your case,

module.exports.initClass = function (params){
...
}

module.exports.getInstance = function (){
}

When importing it 

var init = require('./class.') // init object has two keys -> initClass and getInstance
 init.initClass('abc')
 init.getInstance()

Upvotes: 2

Always Learning
Always Learning

Reputation: 5581

You're making it more complex than needed. Once you have your functions defined, you can export it with this:

module.exports = {
  initClass,
  getInstance
}

To use it, you do this:

const init = require("./class.js");
init.initClass(params);
const instance = init.getInstance();

What you're exporting from the module is an object (which I've named init in the example above) that contains two functions. You don't have to pass arguments to the functions at the time you require.

Upvotes: 3

Mr.Throg
Mr.Throg

Reputation: 1005

If i'm understanding correctly you are trying to export multiple methods if that is the case simple use this. 

   module.exports = {
        method: function() {},
        otherMethod: function(parmas) {}
    }

In your code use like this.

 var init = require('./class.js');
    init.method()
    init.otherMethond(paramObj)

If you want below scenario you need to check out about method chaining. 

var init = require('./class.js').init(params).initClass(params);

Upvotes: 1

Related Questions