Easy Worker Queue

Easy Worker Queue is a lightweight library designed for managing asynchronous tasks in Node.js applications efficiently, using worker threads. It simplifies the process of handling task execution, errors, and completion.

Installation

You can install Easy Worker Queue via npm:

npm install easy-worker-queue

Usage

const { Queue } = require("easy-worker-queue");
const path = require("path");

// Create a new instance of the Queue
const queue = new Queue();

// Create a named queue "firstQueue" with a worker file and optional configurations
queue.createNameSpace("firstQueue", path.join(__dirname, "worker.js"), {
  isAsync: true,
  onError: (err) => {
    console.log(err);
  },
  onExit: (exitCode) => {
    console.log(exitCode);
  },
  onSuccess: (data) => {
    console.log(data);
  },
  jobsLimit: 5,
});

// Create another named queue "secondQueue" with a different worker file
queue.createNameSpace("secondQueue", path.join(__dirname, "other-worker.js"), {
  isAsync: true,
  onError: (err) => {
    console.log(err);
  },
  onExit: (exitCode) => {
    console.log(exitCode);
  },
  onSuccess: (data) => {
    console.log(data);
  },
});

// Enqueue tasks to the created queues at intervals
setInterval(() => {
  queue.enqueue("firstQueue", 123);
  queue.enqueue("secondQueue", { message: "ok" });
}, 5000);

Explanation

In this example:

• Note: The worker.js file must be a JavaScript file that exports a default function using module.exports.
• Two named queues, "firstQueue" and "secondQueue", are created using queue.createNameSpace().
• Each queue is associated with a specific worker file (worker.js and other-worker.js).
• Optional configuration options such as error handling (onError), exit handling (onExit), success handling (onSuccess), and job limit (jobsLimit) can be specified.
• Tasks are enqueued to the queues at regular intervals using queue.enqueue().

Using CronQueue for Scheduled Tasks

const { CronQueue } = require("easy-worker-queue");
const path = require("path");

// Create a new instance of the CronQueue
const queue = new CronQueue();

// Create a named queue "firstQueue" with a worker file and optional configurations
queue.createNameSpace("firstQueue", path.join(__dirname, "worker.js"), {
  isAsync: true,
  onError: (err) => {
    console.log(err);
  },
  onExit: (exitCode) => {
    console.log(exitCode);
  },
  onSuccess: (data) => {
    console.log(data);
  },
  jobsLimit: 5,
});

// Create another named queue "secondQueue" with a different worker file
queue.createNameSpace("secondQueue", path.join(__dirname, "other-worker.js"), {
  isAsync: true,
  onError: (err) => {
    console.log(err);
  },
  onExit: (exitCode) => {
    console.log(exitCode);
  },
  onSuccess: (data) => {
    console.log(data);
  },
});

// Schedule tasks for the created queues using cron expressions
queue.schedule("firstQueue", "* * * * *");
queue.schedule("secondQueue", "*/3 * * * *");

Explanation

In this example:

• Note: The worker.js file must be a JavaScript file that exports a default function using module.exports.
• Two named queues, "firstQueue" and "secondQueue", are created using queue.createNameSpace().
• Each queue is associated with a specific worker file (worker.js and other-worker.js).
• Optional configuration options such as error handling (onError), exit handling (onExit), success handling (onSuccess), and job limit (jobsLimit) can be specified.
• The CronQueue class allows scheduling tasks based on cron expressions.
• The schedule() method of the CronQueue class is used to schedule tasks for each queue, specifying the cron expression.

Properties

name

• Description: Specifies the name of the queue namespace.
• Type: String
• Example: "firstQueue"

workerPath

• Description: Specifies the path to the worker file associated with the queue.
• Type: String
• Example: path.join(__dirname, "worker.js")

options

• Description: Optional configuration options for the queue.
• Type: Object
• Properties:
  • isAsync: Indicates whether the worker function is asynchronous.
    • Type: Boolean
    • Default: false
    • Example: true
  • onError: Callback function to handle errors that occur during task execution.
    • Type: Function
    • Default: undefined
    • Example:

      onError: (err) => {
        console.log(err);
      };

  • onExit: Callback function to handle the exit event of the worker thread.
    • Type: Function
    • Default: undefined
    • Example:

      onExit: (exitCode) => {
        console.log(exitCode);
      };

  • onSuccess: Callback function to handle successful completion of tasks.
    • Type: Function
    • Default: undefined
    • Example:

      onSuccess: (data) => {
        console.log(data);
      };

  • jobsLimit: Specifies the maximum number of jobs that can be queued before skipping new ones.
    • Type: Number
    • Default: undefined
    • Example: 5