Multiplexed Promise

Multiplexed promise is a tiny, zero-dependency library that allows you to create a promise that can be resolved by multiple consumers.

Think of it like one promise, multiple awaiters.

Common uses;

• Firing a fetch request once in response to two or more simultaneous events
• ??

Get Started

CodeSandbox Example

Example

import MultiplexedPromise from "multiplexed-promise";

// Create a "promise generator" - a function that returns a promise
const pokemonFetcher = () => fetch(`https://pokeapi.co/api/v2/pokemon/ditto`);

// Create a multiplexed version - this should live in a "service" or "utility" file, where it can be shared by multiple components
const fetchPokemon = MultiplexedPromise(pokemonFetcher);

// Create a handler to handle the result of the multiplexed promise - in the case of a fetch response, we need to clone it
const getPokemon = () => fetchPokemon().then((r) => r.clone().json());

// Use it

getPokemon(); // Will fire the promise generator (fetcher)
await getPokemon(); // Will subscribe to the response from the first call

getPokemon(); // Will fire the promise generator again, as the first promise has resolved.

Installation

Install via NPM:

npm install multiplexed-promise

Or with Yarn:

yarn add multiplexed-promise