@nestjs-enhanced/pg-boss v1.2.4

pg-boss

A nestjs toolkit for interacting with integrate with pg-boss, a job queue system for PostgreSQL. It offers a more 'nest' style way to register workers and schedule work.

Install:

npm install pg-boss @nestjs-enhanced/pg-boss

Usage:

Background work:

import { ProcessQueue } from '@nestjs-enhanced/pg-boss';

@Injectable()
export class MyWorkerService {
  @ProcessQueue('some-queue-name')
  processSomeQueue(job: Job) {
    // do work with job
  }
}

import { PgBoss } from '@nestjs-enhanced/pg-boss';

@Injectable()
export class MyOtherService {
  constructor (
    private pgBoss: PgBoss
  )

  doWork() {
    this.pgBoss.send('some-queue-name', {
      // data can be passed through the job
      id: someRecord.id
    });
  }
}

Cron style work:

import { PgBoss } from '@nestjs-enhanced/pg-boss';

@Injectable()
export class MyOtherService {
  constructor (
    private pgBoss: PgBoss
  )

  @ScheduledQueue('* * * * *')
  doWork() {
    // do work every minute of every day
  }
}

QueueModule

register:

import { QueueModule } from 'path-to-queue-module';

@Module({
  imports: [
    QueueModule.register({
      database: 'your-database-connection-string-or-config'
      // ... other PgBoss options
    })
  ]
})
export class AppModule {}

registerAsync:

import { QueueModule } from 'path-to-queue-module';

@Module({
  imports: [
    QueueModule.registerAsync({
      useFactory: async (configService) => {
        return {
          database: configService.get('DATABASE_URL')
          // ... other PgBoss options
        };
      },
      inject: [ConfigService],
    })
  ]
})
export class AppModule {}

Decorators

ProcessQueue

The ProcessQueue decorator calls the work method of pg-boss and can perform a job on a specific queue. It follows the work method of pg-boss.

It takes a queue name and an options object to control how the work is done.

ScheduledQueue

The ScheduledQueue decorator calls the schedule method of pg-boss and can perform a job on a schedule. It is useful for running work on a schedule where only one worker should be processing it at a time.

It takes a string of the cron schedule and an optional options object to control how the job is scheduled

QueueMiddlewareService

The QueueMiddlewareService provides a way to register middlewares that get called for each job coming through the queue. These middlewares follow the express pattern, taking in a job and a next function, and can be used to execute any pre/post-processing steps on jobs like logging or cleanup.

Usage:

To use the middleware service, you first need to inject it into your service or controller:

import { QueueMiddlewareService } from 'path-to-queue-middleware-service';

@Injectable()
export class YourService {
  constructor(private queueMiddlewareService: QueueMiddlewareService) {}

  yourMethod() {
    this.queueMiddlewareService.register((job, next) => {
      // Your middleware logic here
      next();
    });
  }
}

Here, job represents the current job being processed in the queue, and next is a callback function that, when called, moves on to the next middleware in the queue (or finalizes the job if there are no more middlewares).

Future:

• Wrap pg-boss into a SchedulingService to avoid direct interaction and to simplify interactions with pg-boss
• Create new queue package that hooks into pg-boss or other types of queueing services