Package Exports

workers-pool

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Readme

workers-pool

Creating truly asynchronus functions has never been easier!

The workers-pool package allows you to easily create a pool of workers, pass them some heavy tasks in the form of functions, and use the generated async function as asynchronous Promise-based functions.

Important note 1: This is not yet fully tested, so be careful while using it!
Important note 2: Currently there is supports for only node environment!

Installing the package

npm i workers-pool

Usage

functions.js

const { Pool } = require('workers-pool');
const {isMainThread} = require('worker_threads');

// Some function to be made asynchronous
function add (a, b) {
    return a + b;
}

function sub (a, b) {
    return a - b;
}

// Step 1: export the functions
module.exports.add = add;
module.exports.sub = sub;

if (isMainThread){
    // Step 2: create a pool (can create a 
    // separate pool for separate functions)
    const myPool = new Pool({
        taskRunners: [
            {name: 'add', job: add, threadCount: 4},
            {name: 'sub', job: sub, threadCount: 4},
        ],
        totalThreadCount: 8,
        lockTaskRunnersToThreads: true,
        allowDynamicTaskRunnerAddition: false,
    });

    // Step 3: generate the async version of the functions
    let addAsync = myPool.getAsyncFunc('add');
    let subAsync = myPool.getAsyncFunc('sub');

    // Step 4: export the new async functions
    module.exports.addAsync = addAsync;
    module.exports.subAsync = subAsync;
    module.exports.myPool = myPool;
}

index.js

const {addAsync, subAsync, myPool} = require('./functions.js')
    
async function test() {
    try {
        let result = await addAsync(2, 5);
        console.log(result); // output: 7
    } catch (error) {
        console.log(error);
    }

    try {
        let result = await subAsync(100, 10);
        console.log(result) // output: 90
    } catch (error) {
        console.log(error);
    }
}

test().then(() => {
    myPool.terminate();
});

Note isMainThread is essential to defferentiate whether a file is being run in the main thread or a worker thread, so it can be used to prevent certain parts of the code, especially pool and async functions creation, from being recursively run as shown in the example.

Status

You can also get the status of the pools:

const Pool = require('workers-pool');

Pool.status();     // brief info about the pools
Pool.status(true); // Verbose info about the pools