support-event

Getting Start

This package implemented to distribute huge task to some workers by RabbitMQ broker. For example, manipulate the image uploaded to server wast many server resources and time, on this situation we could create a task and distribute the image manipulation into other services and servers, and when the task finished we will have the new images without waiting for manipulation.

This package has two main features:

1. Tasks
2. Workers

Initializing

import { Broker } from '@del-internet/support-broker';

const broker = new Broker({
  hostname: 'hostname...',
  username: 'username...',
  password: 'password...',
});

Tasks

The main idea behind Task Queues is to avoid doing a resource-intensive task immediately and having to wait for it to complete. Instead we schedule the task to be done later. We encapsulate a task as a message and send it to a queue. A worker process running in the background will pop the tasks and eventually execute the job.

to create a task you have to create a class like so:

import { Task } from '@del-internet/support-broker';

class ResizeImage extends Task {
  payload(): Record<string, unknown> {
    return {
      id: ....,
    };
  }
}

each task has a payload method that allow you pass the task requirements.

Distribute a task

After creating a task you should register it by the broker:

await broker.distribute(new ResizeImage());

Workers

When you send a task to the broker service, the broker service waiting for workers to handle the task. each worker receive a task data, and doing desired required on it. for example: "ResizeImageWorker" could resize the image by url or id received from the task.

to create a worker you have to create a class like so:

import { Worker } from '@del-internet/support-broker';

class ResizeImageWorker extends Worker {
  async handle({ payload: { id } }: Record<string, unknown>): Promise<void> {
    // do resizing operation
  }
}

each worker has a handle method that receive a object contained task "payload". you have to do the task operations on this method.

Registering a worker task

After creating a worker you should register it by the broker:

await broker.register(new ResizeImageWorker());