fix(services): add Kafka microservice for @MessagePattern to work

The @MessagePattern decorator requires connectMicroservice() to work.
Without this configuration, services could not consume Kafka messages
via @MessagePattern, causing events to be lost.

Fixed services:
- planting-service: ACK consumption
- identity-service: event consumption
- reward-service: event consumption

blockchain-service already had this configured.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/services/identity-service/src/main.ts

@@ -1,9 +1,11 @@
 import { NestFactory } from '@nestjs/core';
-import { ValidationPipe } from '@nestjs/common';
+import { ValidationPipe, Logger } from '@nestjs/common';
 import { SwaggerModule, DocumentBuilder } from '@nestjs/swagger';
+import { MicroserviceOptions, Transport } from '@nestjs/microservices';
 import { AppModule } from './app.module';
 
 async function bootstrap() {
+  const logger = new Logger('Bootstrap');
   const app = await NestFactory.create(AppModule);
 
   // Global prefix
@@ -36,10 +38,30 @@ async function bootstrap() {
   const document = SwaggerModule.createDocument(app, config);
   SwaggerModule.setup('api/docs', app, document);
 
+  // Kafka 微服务 - 用于 @MessagePattern 消费消息
+  const kafkaBrokers = process.env.KAFKA_BROKERS?.split(',') || ['localhost:9092'];
+  const kafkaGroupId = process.env.KAFKA_GROUP_ID || 'identity-service-group';
+
+  app.connectMicroservice<MicroserviceOptions>({
+    transport: Transport.KAFKA,
+    options: {
+      client: {
+        clientId: 'identity-service',
+        brokers: kafkaBrokers,
+      },
+      consumer: {
+        groupId: kafkaGroupId,
+      },
+    },
+  });
+
+  await app.startAllMicroservices();
+  logger.log('Kafka microservice started');
+
   const port = process.env.APP_PORT || 3000;
   await app.listen(port);
-  console.log(`Identity Service is running on port ${port}`);
-  console.log(`Swagger docs: http://localhost:${port}/api/docs`);
+  logger.log(`Identity Service is running on port ${port}`);
+  logger.log(`Swagger docs: http://localhost:${port}/api/docs`);
 }
 
 bootstrap();

backend/services/planting-service/src/main.ts

@@ -1,6 +1,7 @@
 import { NestFactory } from '@nestjs/core';
 import { ValidationPipe, Logger } from '@nestjs/common';
 import { SwaggerModule, DocumentBuilder } from '@nestjs/swagger';
+import { MicroserviceOptions, Transport } from '@nestjs/microservices';
 import { AppModule } from './app.module';
 
 async function bootstrap() {
@@ -41,6 +42,27 @@ async function bootstrap() {
   const document = SwaggerModule.createDocument(app, config);
   SwaggerModule.setup('api/docs', app, document);
 
+  // Kafka 微服务 - 用于接收 ACK 确认消息
+  const kafkaBrokers = process.env.KAFKA_BROKERS?.split(',') || ['localhost:9092'];
+  const kafkaGroupId = process.env.KAFKA_GROUP_ID || 'planting-service-group';
+
+  app.connectMicroservice<MicroserviceOptions>({
+    transport: Transport.KAFKA,
+    options: {
+      client: {
+        clientId: 'planting-service-ack',
+        brokers: kafkaBrokers,
+      },
+      consumer: {
+        groupId: `${kafkaGroupId}-ack`,
+      },
+    },
+  });
+
+  // 启动 Kafka 微服务
+  await app.startAllMicroservices();
+  logger.log('Kafka microservice started for ACK consumption');
+
   const port = process.env.APP_PORT || 3003;
   await app.listen(port);
 

backend/services/reward-service/src/main.ts

@@ -1,6 +1,7 @@
 import { NestFactory } from '@nestjs/core';
 import { ValidationPipe, Logger } from '@nestjs/common';
 import { SwaggerModule, DocumentBuilder } from '@nestjs/swagger';
+import { MicroserviceOptions, Transport } from '@nestjs/microservices';
 import { ConfigService } from '@nestjs/config';
 import { AppModule } from './app.module';
 
@@ -38,6 +39,26 @@ async function bootstrap() {
   const document = SwaggerModule.createDocument(app, config);
   SwaggerModule.setup('api', app, document);
 
+  // Kafka 微服务 - 用于 @MessagePattern 消费消息
+  const kafkaBrokers = process.env.KAFKA_BROKERS?.split(',') || ['localhost:9092'];
+  const kafkaGroupId = process.env.KAFKA_GROUP_ID || 'reward-service-group';
+
+  app.connectMicroservice<MicroserviceOptions>({
+    transport: Transport.KAFKA,
+    options: {
+      client: {
+        clientId: 'reward-service',
+        brokers: kafkaBrokers,
+      },
+      consumer: {
+        groupId: kafkaGroupId,
+      },
+    },
+  });
+
+  await app.startAllMicroservices();
+  logger.log('Kafka microservice started');
+
   await app.listen(port);
   logger.log(`${appName} is running on port ${port}`);
   logger.log(`Swagger documentation available at http://localhost:${port}/api`);