tiny-async-task-queue

tiny-async-task-queue

Introduction

Here is a tiny async task queue, for several standalone task executing in order, with just one API.

Usage

npm i -S tiny-async-task-queue

const Queue = require('tiny-async-task-queue')
const queue = new Queue()

And the only API is add.

queue.add(task1)
queue.add(task2)
queue.add(task3)

task1, task2, task3, will executing one by one.

Tasks need according with ONE OF the rules below.

• Supply an argument typed Function, invoke it when the task is finished.
• Return a Promise.

If your code satisfied with two rules, first finished rule will be triggered, and the second will be ignored.

For example:

your task can write like this

function task(next) {
    setTimeout(() => {
        // do something...
        next()
    }, 500)
}

or this

function task() {
    return new Promise(resolve => {
        setTimeout(() => {
            // do something...
            resolve()
        }, 500)
    })
}

If the task added to the empty queue, it will run immediately, otherwise it will be executed after other tasks finished.

And the internal queue based on tiny-linked-queue, if you want to manipulate the internal queue you can use the queue property.

const queue = new Queue()
queue.queue // => this property pint to the `tiny-linked-queue`.

Full demo

function task1(next) {
    setTimeout(() => {
        console.log('task1 running.')
        next()
    }, 100)
}

function task2() {
    return new Promise(resolve => {
        setTimeout(() => {
            console.log('task2 running.')
            resolve()
        }, 50)
    })
}

function task3() {
    console.log('task3 running.')
}

const Queue = require('tiny-async-task-queue')
const queue = new Queue()
queue.add(task1)
queue.add(task2)
queue.add(task3)

// console will logs as below:
// task1 running.
// task2 running.
// task3 running.

Tests

yarn test