The microservices package enables multi-transport communication between services, supporting Redis, RabbitMQ, TCP, and more.

Installation

bun add ioredis   # Redis transport
bun add amqplib   # RabbitMQ transport

Setup

import { createElysiaApplication } from "nestelia";
import { Transport } from "nestelia/microservices";

const app = await createElysiaApplication(AppModule);

app.connectMicroservice({
  transport: Transport.REDIS,
  options: { host: "localhost", port: 6379 },
});

await app.startAllMicroservices();
app.listen(3000); // HTTP + microservices hybrid

Transports

enum Transport {
  REDIS = "REDIS",
  RABBITMQ = "RABBITMQ",
  TCP = "TCP",
  GRPC = "GRPC",
  KAFKA = "KAFKA",
  MQTT = "MQTT",
  NATS = "NATS",
}

Message Patterns

Request/Response

Use @MessagePattern() for request/response communication:

import { Controller } from "nestelia";
import { MessagePattern, Payload } from "nestelia/microservices";

@Controller()
class MathController {
  @MessagePattern("sum")
  sum(@Payload() data: { numbers: number[] }) {
    return data.numbers.reduce((a, b) => a + b, 0);
  }
}

Event-Based

Use @EventPattern() for fire-and-forget events:

import { EventPattern, Payload } from "nestelia/microservices";

@Controller()
class NotificationController {
  @EventPattern("user.created")
  handleUserCreated(@Payload() data: { userId: string }) {
    console.log("New user:", data.userId);
  }
}

Client Factory

Send messages to other microservices:

import { Injectable } from "nestelia";
import { ClientFactory, Transport } from "nestelia/microservices";

@Injectable()
class OrderService {
  private client = ClientFactory.create({
    transport: Transport.REDIS,
    options: { host: "localhost", port: 6379 },
  });

  async calculateTotal(items: any[]) {
    return this.client.send("sum", { numbers: items.map((i) => i.price) });
  }
}

Hybrid Application

Run HTTP and microservice listeners in the same process:

const app = await createElysiaApplication(AppModule);

// HTTP routes work as normal
// Plus microservice message handlers
app.connectMicroservice({
  transport: Transport.REDIS,
  options: { host: "localhost", port: 6379 },
});

await app.startAllMicroservices();
app.listen(3000);