promise-utilities

A collection of helper methods based on promises

Utility Functions

1. promisify

promisify is very useful method to create a promise and resolve it later.

Usage

const [promise, resolver] = promisify();

promise.then(() => {
    console.log('this promise is resolved');
});

....

resolver(); // Also pass a value for above subscription.

2. promisedPubSub

promisedPubSub is another useful method to create a pub-sub model out of promises.

Usage

const [promise, resolver] = promisedPubSub();

function Method1() {
    return promise.then((val) => {
        console.log('subscriber 1', val);
    });
}

function Method2() {
    return promise.then((val) => {
        console.log('subscriber 2', val);
    });
}

const unsubscribeMeth1 = Method1();
const unsubscribeMeth2 = Method1();

....


resolver('value 1'); // logs subscriber 1 value 1, subscriber 2 value 1

resolver('value 2'); // logs subscriber 1 value 2, subscriber 2 value 2

unsubscribeMeth1();

resolver('value 3'); // logs subscriber 2 value 3