Job

Job is a simple library for cancellable asynchronous tasks. Job was inspired by Kotlin coroutines and tries to bring some of the same functionality to TypeScript/JavaScript.

Documentation

• Installation
• Usage
• Build Info
• API
• Example Project
• Release Notes

Installation

job can be installed using NPM or Yarn. The scripts provided by the NPM package are UMD scripts and will also work as script tags. If using script tags, you must load the UMD scripts for @ethossoftworks/outcome before the scripts for @ethossoftworks/job.

yarn add @ethossoftworks/job

Usage

Simple Job

import { Job } from "@ethossoftworks/job"

const result = await new Job(async (job) => {
    await job.delay(1000)
    return Outcome.ok("Success")
}).run()

Cancel a Job

Every job is cancellable. Cancelling will stop the job at the next "pause" point. Pause points are created with job.pause() or the inbuilt job.delay()

import { Job } from "@ethossoftworks/job"

const job = new Job(async (job) => {
    await job.delay(1000)
    return Outcome.ok("Success")
})

setTimeout(() => job.cancel(), 500) // This stops the job after 500 milliseconds
const result = await job.run()

if (Job.isCancelled(result)) {
    // This block will run
}

Children Jobs

Jobs may have children jobs launched from them. When the parent completes or is cancelled, children jobs will be cancelled if they have not already completed.

import { Job } from "@ethossoftworks/job"

// Launch multiple children in parallel
new Job(async (job) => {
    const child1 = job.launchAndRun(async (job) => {
        await job.delay(2000)
        return Outcome.ok(true)
    })

    const child2 = job.launchAndRun(async (job) => {
        await job.delay(1000)
        return Outcome.ok(true)
    })

    const results = await Promise.all([child1, child2])
    return Outcome.ok("Success")
})

// Launch multiple children sequentially
new Job(async (job) => {
    const child1 = await job.launchAndRun(async (job) => {
        await job.delay(2000)
        return Outcome.ok(true)
    })

    const child2 = await job.launchAndRun(async (job) => {
        await job.delay(1000)
        return Outcome.ok(true)
    })

    return Outcome.ok("Success")
})

Build Info

Build

yarn build or yarn build-dev

Develop

1. Open two terminals
2. Run yarn start-ts in the first
3. Run yarn start-bundler in the second

Test

yarn build-test or yarn test