TaskTimer


Build Status Coverage Status Dependencies Known Vulnerabilities Maintained
npm Release License TypeScript Documentation
© 2019, Onur Yıldırım (@onury).


An accurate timer utility for running periodic tasks on the given interval ticks or dates.

Why TaskTimer?


Because of the single-threaded, asynchronous nature of JavaScript, each execution takes a piece of CPU time, and the time they have to wait will vary, depending on the load. This creates a latency and cumulative difference in asynchronous timers; that gradually increase the inacuraccy. TaskTimer claims to be the best timer that overcomes this problem as much as possible.

Secondly, I needed a task manager that can handle multiple tasks on different intervals, with a single timer instance.

Features


Installation


npm i tasktimer

Usage


In Node/CommonJS environments:

const { TaskTimer } = require('tasktimer');

With transpilers (TypeScript, Babel):

import { TaskTimer } from 'tasktimer';

In (Modern) Browsers:

<script src="js/tasktimer.min.js"></script>
<script>
    const { TaskTimer } = tasktimer;
</script>

Simplest Example

const timer = new TaskTimer(1000);
timer.add(task => console.log(`Current runs: ${task.currentRuns}`)).start();

Regular Timer (without Task Management)

const timer = new TaskTimer(5000);
timer.on('tick', () => console.log(`Tick count: ${timer.tickCount}`));
timer.start();

Detailed Example

// Timer with 1000ms (1 second) base interval resolution.
const timer = new TaskTimer(1000);
// interval can be updated anytime by setting the `timer.interval` property.

// Add multiple tasks (at once) based on tick intervals.
timer.add([
    {
        id: 'task-1',       // unique ID of the task
        tickInterval: 5,    // run every 5 ticks (5 x interval = 5000 ms)
        totalRuns: 10,      // run 10 times only. (set to 0 for unlimited times)
        callback(task) {
            // code to be executed on each run
            console.log(`${task.id} task has run ${task.currentRuns} times.`);
        }
    },
    {
        id: 'task-2',       // unique ID of the task
        tickDelay: 1,       // 1 tick delay before first run
        tickInterval: 10,   // run every 10 ticks (10 x interval = 10000 ms)
        totalRuns: 2,       // run 2 times only. (set to 0 for unlimited times)
        callback(task) {
            // code to be executed on each run
            console.log(`${task.id} task has run ${task.currentRuns} times.`);
        }
    }
]);

// You can also execute some code on each tick... (every 1000 ms)
timer.on('tick', () => {
    console.log('tick count: ' + timer.tickCount);
    console.log('elapsed time: ' + timer.time.elapsed + ' ms.');
    // stop timer (and all tasks) after 1 hour
    if (timer.tickCount >= 3600000) timer.stop();
});

// Start the timer
timer.start();

How it works


(e.g. task1 runs on every 10th tick, task2 runs on every 30th)

Documentation

See API reference and examples here.

Changelog


See CHANGELOG.md.
If you're migrating from TaskTimer v1 to v2+, there are various breaking changes!..

Contributing


Clone original project:

git clone https://github.com/onury/tasktimer.git

Install dependencies:

npm install

Add tests into test/node and test/browser and run:

npm run test!   # builds and runs tests
npm test        # runs tests without building

Use included tslint.json and editorconfig for style and linting.
Travis build should pass, coverage should not degrade.

License


MIT.