NestJS Microservices: Medical Platform Architecture

// api-gateway/src/main.ts
import { NestFactory } from '@nestjs/core'
import { AppModule } from './app.module'

async function bootstrap() {
  const app = await NestFactory.create(AppModule)

  // Proxy to microservices
  app.setGlobalPrefix('api/v1')

  await app.listen(3000)
}

// consultation.service.ts
async completeConsultation(consultationId: string) {
  const consultation = await this.consultationRepo.findById(consultationId)
  consultation.status = 'completed'
  await consultation.save()

  // Publish event
  await this.redisClient.publish('consultation.completed', {
    consultationId,
    patientId: consultation.patientId,
    doctorId: consultation.doctorId
  })
}

// medical-records.service.ts - Subscriber
this.redisClient.subscribe('consultation.completed')
this.redisClient.on('message', async (channel, message) => {
  if (channel === 'consultation.completed') {
    const data = JSON.parse(message)
    // Update medical record automatically
    await this.updateMedicalRecord(data)
  }
})

// notification.gateway.ts
@WebSocketGateway({ namespace: 'notifications' })
export class NotificationGateway {
  @WebSocketServer() server: Server

  async sendToUser(userId: string, notification: any) {
    this.server.to(`user:${userId}`).emit('notification', notification)
  }
}

version: '3.8'
services:
  auth-service:
    build: ./services/auth
    environment:
      - DATABASE_URL=postgresql://...
      - REDIS_URL=redis://redis:6379
    depends_on:
      - postgres
      - redis

  consultation-service:
    build: ./services/consultation
    environment:
      - DATABASE_URL=postgresql://...
      - MONGO_URL=mongodb://mongo:27017
    depends_on:
      - postgres
      - mongo