Installation

Install via NPM:

npm install @saiuttej/nestjs-sqs-queue

Install via Yarn:

yarn add @saiuttej/nestjs-sqs-queue

Install via PNPM:

pnpm add @saiuttej/nestjs-sqs-queue

Quick Start

Register Module

@Module({
  imports: [
    SQSQueueModule.forRoot({
      queues: [],
    }),
  ],
})
class AppModule {}

Quite often you might want to asynchronously pass module options instead of passing them beforehand. In such case, use forRootAsync() method like many other Nest.js libraries.

@Module({
  imports: [
    SQSQueueModule.forRootAsync({
      useFactory: (...deps) => {
        return {
          clients: [],
        };
      },
      inject: [...dependencies],
    }),
  ],
})
class AppModule {}

Module Configuration

import { Module } from '@nestjs/common';
import { QueueExecutionType, SQSQueueModule } from '@saiuttej/nestjs-sqs-queue';
import { AppController } from './app.controller';
import { AppService } from './app.service';

@Module({
  imports: [
    SQSQueueModule.forRoot({
      queues: [
        {
          key: 'unique-key-for-queue',
          queue: {
            accountId: 'aws-account-id',
            queueName: 'queue-name',
            region: 'aws-region',
          },
        },
      ],
    }),
  ],
  controllers: [AppController],
  providers: [AppService],
})
export class AppModule {}

• key* - Unique key for the queue, used to identify the queue, should be unique across all queues in the application.
• queue* - Queue configuration object
  • accountId* - AWS Account ID
  • queueName* - SQS Queue Name
  • region* - AWS Region
  • useQueueUrlAsEndpoint - Use Queue URL as endpoint for producer and consumer
• sqsConfig - AWS SQSClient constructor options,
• autoCreateQueue - Auto create queue if not exists (default: false)
• consumerOptions - AWS SQSConsumer options
• producerOptions - AWS SQSProducer options
• executionTypes - Execution types (default: [QueueExecutionType.RECEIVE, QueueExecutionType.SEND])

Producer

import { Injectable } from '@nestjs/common';
import { SQSQueueService } from '@saiuttej/nestjs-sqs-queue';

@Injectable()
export class AppService {
  constructor(private readonly sqsQueueService: SQSQueueService) {}

  async sendMessage() {
    await this.sqsQueueService.send('unique-key-for-queue', {
      id: '123',
      body: 'message-body',
    });
  }
}

SQSQueueService provides the send method to send messages to the queue. send method takes two arguments:

• key* - Unique key for the queue
• message* - It can be a String, Message Object, or Array of Message Objects or Strings

Consumer

Processing a single message

import { Injectable } from '@nestjs/common';
import { OnQueueMessage } from '@saiuttej/nestjs-sqs-queue';

@Injectable()
export class AppService {
  @OnQueueMessage({ key: 'my-sqs-queue' })
  async queueHandler(message: Message) {
    console.log(message);
  }
}

Processing multiple messages

import { Injectable } from '@nestjs/common';
import { OnQueueMessage } from '@saiuttej/nestjs-sqs-queue';

@Injectable()
export class AppService {
  @OnQueueMessage({ key: 'my-sqs-queue', batch: true })
  async queueHandler(message: unknown | unknown[] | Message | Message[]) {
    console.log(message);
  }
}

OnQueueMessage decorator is used to listen to messages from the queue. OnQueueMessage decorator takes an object with the following properties:

• key* - Unique key for the queue
• batch - Boolean value to indicate whether to process messages in batch or not (default: false)

By default the handler function, which is annotated with the OnQueueMessage decorator, it will receive the SQS message object(s) to the function. But you can also customize the SQS message object(s) by using messageFormatter in consumerOptions, when configuring the queue.

But you need to remember that if the response return by the handler function is not void or Promise<void>, then the response should be an Object having the parameter MessageId, if it is batch operation then the response should be an Array of Objects, each Object having the parameter MessageId. This is required to delete the message from the queue after processing.

Note: Only one handler can be registered for a queue key.

Contributing

Contributions welcome! See Contributing.

Author

B Sai Uttej

License

Licensed under the MIT License - see the LICENSE file for details.