memoq

A simple task queue that stores the output of each task and associates it with an id. Future tasks can retrieve old task results and perform operations on it. Additionally, the NodeJS process executing the task queue can be killed and restarted where it left off (assuming cache files have persisted and user-instantiated queue has not been modified).

Installation

# npm
npm i memoq@latest

#pnpm
pnpm add memoq@latest

Usage

import { Queue, Task } from 'memoq';

const queue = new Queue();

queue.add(new Task(
	`root`,							// ID of task
	[],								// Depends on data from no other tasks
	async (data) => {				// `data` is empty object
		return 3;
	}
));

queue.add(new Task(
	`step1`,						// ID of task
	[],								// Depends on data from no other tasks
	async (data) => {				// `data` is empty object
		return 4;
	}
));

queue.add(new Task(
	`step2`,						// ID of task
	[`root`, `step1`],				// Depends on data from task IDs `root` and `step1`
	async (data) => {				// `data` contains cached results
		const dr = data['root'];	// Return value of `root` task
		const ds1 = data['step1'];	// Return value of `step1` task
		const val = dr + ds1;
		console.log(val);			// Outputs 7
		return val;
	}
));

await queue.start();				// Start the queue

Reference

class Queue

public new Queue()

Creates a new instance of Queue

public add(task: Task): void

Adds a Task instance to the queue

• task - the Task to add

public async start(): void

Starts executing tasks in the queue, and recalls prior state from the cache if present

class Task

public new Task(id: string, dependsOn: string[], fn: TaskFunction, delay: Returnable<number>)

Creates a new instance of Task

• id - ID of the new task
• dependsOn - IDs of the data to import into the new task
• fn - the actual function to execute (parameter data given)
• delay - the delay, in ms, before this task begins executing (default 0)
  • This is of type Returnable<number>, which means it can either by of type number or a function that returns a value of type number

Changelog

1.2.0

Improvements

• Queue - added task duration in logging

Bugs

• N/A

1.1.0

Improvements

• Task - delay parameter in constructor modified
• README - Changelog added

Bugs

• N/A

1.0.1

Improvements

• README.md added
• LICENSE added

Bugs

• N/A

1.0.0

Improvements

• Package created

Bugs

• N/A

Built with ❤️ by @RyloRiz