NestJS Kafka Microservice with REST Endpoints

September 21, 2022

I am new to NestJS and was wondering if its possible to have a NestJS Kafka micro-service with REST Endpoints as well (ideally using Fastify).

I have found the following configuration for both Kafka and for Fastify but it seems like you can only have one or the other in the same service.

// kafka config

const app = await NestFactory.createMicroservice<MicroserviceOptions>(AppModule, {
    transport: Transport.KAFKA,
    options: {
      client: {
        brokers: ['localhost:9092'],
      },
    },
  });

// Fastify config

const app = await NestFactory.create<NestFastifyApplication>(AppModule, new FastifyAdapter(), {
    bufferLogs: true,
  });

Does anybody know if there is a way to configure both ?.

>Solution :

What you’re looking for is called a hybrid application. First configure the HTTP engine:

const app = await NestFactory.create<NestFastifyApplication>(AppModule, new FastifyAdapter(), {
 bufferLogs: true,
});

Then you use connectMicroservices:

app.connectMicroservices<MicroserviceOptions>(AppModule, {
  transport: Transport.KAFKA,
  options: {
    client: {
      brokers: ['localhost:9092'],
    },
  },
});

then you call app.startAllMicroservices(), and finally you app.listen(port)