Bull Graceful Shutdown NestJS

example.ts

import { BullModule } from '@nestjs/bull';
import { Module } from '@nestjs/common';
import { QueueGracefulShutdown } from './queue-graceful-shutdown';

const QUEUE_NAME = 'my-queue';

@Module({
    imports: [
        BullModule.registerQueue({
            name: QUEUE_NAME,
        }),
    ],
    exports: [BullModule],
})
export class MyQueueModule extends QueueGracefulShutdown(QUEUE_NAME) {}

queue-graceful-shutdown.ts

import { InjectQueue } from '@nestjs/bull';
import type { OnModuleDestroy } from '@nestjs/common';
import { Logger } from '@nestjs/common';
import type { Queue } from 'bull';

// eslint-disable-next-line @typescript-eslint/naming-convention
export function QueueGracefulShutdown(queueName: string) {
    class AbstractQueueShutdown implements OnModuleDestroy {
        readonly logger: Logger;

        destroying = false;

        constructor(@InjectQueue(queueName) readonly queue: Queue) {
            this.logger = new Logger(`Shutdown: ${this.queue.name}`);
        }

        async onModuleDestroy(): Promise<void> {
            if (this.destroying) {
                return;
            }

            this.destroying = true;

            const isPaused = await this.queue.isPaused(true);

            if (!isPaused) {
                // Only pause this server from processing, not the entire queue across all servers.
                // This will pause the queue from taking new jobs but allow active ones to finish
                this.logger.log('Pausing for shutdown.');
                await this.queue.pause(true);
                this.logger.log('Paused');
            } else {
                this.logger.log('Already paused');
            }

            // Once all jobs are finished then we can allow the server to shut down.
            this.logger.log('Waiting for this workers job to finish.');
            await this.queue.whenCurrentJobsFinished();
            this.logger.log('All jobs for this worker have finished.', this.queue.name);
        }
    }

    return AbstractQueueShutdown;
}