@alterior/tasks

A framework for enqueuing and processing jobs from Redis queues in Typescript. Build background task runners with this.

Getting started

Install the Alterior runtime, the DI library, and the tasks module:

npm install reflect-metadata
npm install @alterior/runtime @alterior/di @alterior/tasks

A minimal example

First, build a task worker:

import { Worker } from '@alterior/tasks';
import { Logger } from '@alterior/logger';

export class MyTaskHost extends Worker {
    constructor(
        private logger : Logger,
        private taskRunner : TaskRunner
    ) {

    }
    get name() { return '@myorg/mypackage:MyTask'; }

    async transcodeToFormat({ videoId : string, format : string }) {
        this.logger.info('Transcoding to format...');
        run(`ffmpeg /storage/${video}.mp4`);
    }

    async transcode({ videoId : string }) {
        this.logger.info('Queuing transcoding tasks...');

        this.taskRunner.worker()

        await this.enqueue('transcodeToFormat', { videoId: 'abcdef', format: '1080p' });
        await this.enqueue('transcodeToFormat', { videoId: 'abcdef', format: '720p' });
    }
}

However, it is more scalable and type-safe to specify a task per class:

@Task()
export class TranscodeToFormatTask extends TaskRunner {
    execute() {
        run(`ffmpeg /storage/${video}.mp4`);
    }
}

@Task()
export class TranscodeTask extends TaskRunner {
    execute() {
        await TranscodeToFormatTask.enqueue({ videoId: 'abcdef', format: '1080p' });
    }
}

@Module({
    tasks: [ MyTask ]
})
export class MyModule {
}

Application.bootstrap(MyModule, [ TaskRunner ]);