@niur/nestjs-service-bus NPM

Description

Azure Service Bus is a fully managed enterprise message broker with message queues and publish-subscribe topics (in a namespace). Service Bus is used to decouple applications and services from each other, providing the following benefits:

Load-balancing work across competing workers
Safely routing and transferring data and control across service and application boundaries
Coordinating transactional work that requires a high-degree of reliability

Installation

To start building Azure Service Bus-based microservices, first install the required packages:

$ npm i --save @azure/service-bus @niur/nestjs-service-bus

Overview

To use the Azure Service Bus strategy, pass the following options object to the createMicroservice() method:

//  main.ts

const app = await NestFactory.createMicroservice<MicroserviceOptions>(AppModule, {
  strategy: new AzureServiceBusServer({
    connectionString: 'Endpoint=sb://<Name>.servicebus.windows.net/;SharedAccessKeyName=<SharedAccessKeyName>;SharedAccessKey=<SharedAccessKey>',
    options: {}
  }),
});

Options

The Azure Service Bus strategy exposes the properties described below.

Client

@Module({
  imports: [
    AzureServiceBusModule.forRoot([
      {
        name: 'SB_CLIENT',
        connectionString: 'Endpoint=sb://<Name>.servicebus.windows.net/;SharedAccessKeyName=<SharedAccessKeyName>;SharedAccessKey=<SharedAccessKey>',
        options: {},
      },
    ]),
  ]
  ...
})

// or

@Module({
  imports: [
    AzureServiceBusModule.forRootAsync([
      {
        name: 'SB_CLIENT',
        useFactory: (configService: ConfigService) => ({
          connectionString: configService.get('connectionString'),
          options: {}
        }),
        inject: [ConfigService],
      },
    ]),
  ]
  ...
})

@Injectable()
constructor(
  @Inject('SB_CLIENT') private readonly sbClient: AzureServiceBusClientProxy,
) {}

Producer

Event-based

const pattern = {
  name: 'sample-topic', // topic name
  options: {}
}; // queue name
const data = {
  body: 'Example message'
};

this.sbClient.send(pattern, data).subscribe((response) => {
  console.log(response); // reply message
});

Message-based

const pattern = {
  name: 'sample-topic', // topic name
  options: {}
}; // queue name
const data = {
  body: 'Example message'
};
this.sbClient.emit(pattern, data);

Consumer

To access the original Azure Service Bus message use the Subscription decorator as follows:

@Subscription({
    topic: 'sample-topic',
    subscription: 'sample-subscription',
    receiveMode: 'peekLock', // or receiveAndDelete
  })
getMessages(@Payload() message: ServiceBusMessage) {
  console.log(message);
}

Options