Loopback Async Workers

This module provides a component for cron integration and asynchronous execution of scripts using LoopBack. It is designed to leverage the robust LoopBack framework for scheduling and executing worker jobs reliably and efficiently.

Key Features

• Asynchronous execution of worker jobs.
• Integration with LoopBack components for easy and seamless setup.
• Cron job scheduling with fine-grained control over time intervals.
• Comprehensive logging with support for Winston Logger.

Installation

To get started, add the library in your LoopBack project by running:

npm install loopback-async-workers

Configuration

Application Setup

In your application.ts, configure Loopback Async Workers as a component:

import { WorkerComponent } from 'loopback-async-workers';

export class ApiApplication extends BootMixin(
  ServiceMixin(RepositoryMixin(RestApplication)),
) {
  constructor(options: ApplicationConfig = {}) {
    super(options);

    // Other configurations...

    // Add the WorkerComponent
    this.component(WorkerComponent);
    
    // Other configurations...
  }
}

Creating a Worker

To create a worker, define a class extending WorkerJob and use the @workerJob() decorator:

import { inject, service } from '@loopback/core';
import { repository } from '@loopback/repository';
import { WorkerJob, workerJob } from 'loopback-async-workers';
import { ExampleRepository } from '../repositories';
import { ExampleProvider } from '../services';

@workerJob()
export class ExampleWorker extends WorkerJob {
  constructor(
    @repository(ExampleRepository) private exampleRepository: ExampleRepository,
    @service(ExampleProvider) public exampleProvider: ExampleProvider,
  ) {
    super({
      name: 'example-worker',
      onError: (message) => console.error(message),
      onTick: async () => {
        try {
          await this.runProcess();
        } catch (err: any) {
          console.error(`${this.name} ${err.message}`, err);
        }
      },
      limitTime: 600000,
      cronTime: '*/1 * * * *',
    });
  }

  runProcess = async () => {
    // ...run some process
  }
}

Usage

Once you have set up your workers, they will execute based on the cron jobs defined. Each worker job can be independently configured with different intervals and timeout settings.

Testing

To test the workers, use the following command:

npm test

This command will run all the unit tests defined for your worker jobs.

Contributing

If you would like to contribute, please refer to our contribution guidelines.

License

This project is licensed under the terms of the ISC license. See LICENSE for more details.

Support

For any issues, please open a GitHub issue.