Careeroza

Transports

Creating a Microservice

Example

npm i @nestjs/microservices

Example output

added 1 package in 2s

apps/inventory/src/main.ts

import { NestFactory } from '@nestjs/core';
import { MicroserviceOptions, Transport } from '@nestjs/microservices';
import { InventoryModule } from './inventory.module';

async function bootstrap() {
  const app = await NestFactory.createMicroservice<MicroserviceOptions>(InventoryModule, {
    transport: Transport.TCP,
    options: { host: '0.0.0.0', port: 4001 },
  });
  await app.listen();
}
bootstrap();

Choosing a Transport

TransportOptions exampleGood for
TCP{ host, port }Simple request-response inside a private network
Redis{ host, port }Light pub/sub when you already run Redis
RabbitMQ (RMQ){ urls: ['amqp://...'], queue: 'orders_queue', queueOptions: { durable: true } }Reliable work queues, acknowledgements
Kafka{ client: { brokers: ['kafka:9092'] }, consumer: { groupId: 'inventory' } }High-volume event streams, replay, analytics
gRPC{ package: 'catalog', protoPath }Typed, fast service-to-service calls
NATS{ servers: ['nats://...'] }Very fast lightweight messaging
// Kafka consumer service
const app = await NestFactory.createMicroservice<MicroserviceOptions>(NotificationsModule, {
  transport: Transport.KAFKA,
  options: {
    client: { clientId: 'notifications', brokers: ['kafka:9092'] },
    consumer: { groupId: 'notifications-consumer' },
  },
});

// RabbitMQ worker
const worker = await NestFactory.createMicroservice<MicroserviceOptions>(InvoicesModule, {
  transport: Transport.RMQ,
  options: { urls: ['amqp://guest:guest@rabbitmq:5672'], queue: 'invoices', queueOptions: { durable: true }, noAck: false },
});