CADEPT ( Callable Async DEPendency Task ) is an asynchronous task class with dependency management features.

📘 Documentations

Getting Started

Install the package with NPM:

npm i cadept

And require() it:

const Task = require('cadept');

or import it as an ES module:

import Task from 'cadept';

Usage

// Create a task
const task = new Task((resolve, reject) => {

  /* do stuff */

  resolve(); // Finish
});

task(); // Run a task

A task instance is callable just like a function. And it runs asynchronously.

The called task returns a Promise object so you can hook on the task resolution (or rejection) like this:

const task = new Task((resolve, reject) => {
  resolve('Task Complete.');
});

task().then(result => {
  console.log(result); // output: 'Task Complete.'
});

If you prefer simpler syntax, you can also write like this:

const task = new Task(() => {
  return 'Task Complete.';
});

task().then(result => {
  console.log(result); // output: 'Task Complete.'
});

Adding task dependencies

A task can be associated with another tasks as its dependencies.

const task_X = new Task(resolve => {
  console.log('task_X: OK');
  resolve();
});

const task_Y = new Task(resolve => {
  console.log('task_Y: OK');
  resolve();
});

const task_Z = new Task(resolve => {
  console.log('task_Z: OK');
  resolve();
}, [task_X, task_Y]); // Dependencies

task_Z(); // Run task_Z

Output:

task_X: OK
task_Y: OK
task_Z: OK

The 2nd parameter of Task() is an array of dependency tasks, which are task_X and task_Y in the above example. When the dependent task ( task_Z ) is called, it calls its dependencies in parallel, prior to execute its own function, awaiting all the dependencies are resolved.

Alternatively, you can also use depend() to add dependencies to a task.

task_Z.depend(task_X, task_Y);
task_Z();

For more instructions, examples, and advanced usages, please see: 📘 Documentations

And also check the real-world example: p5-livesketch/index.js

---

Author

Satoshi Soma (amekusa.com)