NestJS Nats message ack

Question

Is there a way to manually acknowledge a message if I use NATS for async communication in a NestJS app? This is very common use case where the message is acknowledge after a service is done processing it. If the message is not acknowledged, the server would need to redeliver (just like in the old NATS Streaming library).

@EventPattern({ cmd: 'user:create' })
async createUser(@Payload() user: UserDto, @Ctx() context: NatsContext) {
  await this.emailsService.sendWelcomeEmail(user)
  // need to manually acknowledge the message here but the docs do not provide a way to do so.
}

Answer 1

when using nats-streaming https://www.npmjs.com/package/@nestjs-plugins/nestjs-nats-streaming-transport

@EventPattern(Patterns.UserCreated)
  public async stationCreatedHandler(@Payload() data: { id: number, name: string }, @Ctx() context: NatsStreamingContext) {
    console.log(`received message: ${JSON.stringify(data)}`)
    context.message.ack()
  }

//setup 
    {
        durableName: 'user-queue-group',
        manualAckMode: true,
        deliverAllAvailable: true,
      } /* TransportSubscriptionOptions */ ,
    ),