feat: M0-02 EventBus — sync+async publish + DomainEvents queue

package-lock.json

@@ -14,6 +14,7 @@
         "@nestjs/common": "^11.0.1",
         "@nestjs/config": "^4.0.4",
         "@nestjs/core": "^11.0.1",
+        "@nestjs/event-emitter": "^3.1.0",
         "@nestjs/jwt": "^11.0.2",
         "@nestjs/passport": "^11.0.5",
         "@nestjs/platform-express": "^11.0.1",
@@ -2555,6 +2556,19 @@
         }
       }
     },
+    "node_modules/@nestjs/event-emitter": {
+      "version": "3.1.0",
+      "resolved": "https://registry.npmmirror.com/@nestjs/event-emitter/-/event-emitter-3.1.0.tgz",
+      "integrity": "sha512-DOY/4XBGyIjYyOJKkO6jl1kzFE0ZfX0wV+M2HR5NWymPT9Z0zdCEcZGxTXXkoMRwPtglnvCGJALSjOpXPIcM3g==",
+      "license": "MIT",
+      "dependencies": {
+        "eventemitter2": "6.4.9"
+      },
+      "peerDependencies": {
+        "@nestjs/common": "^10.0.0 || ^11.0.0",
+        "@nestjs/core": "^10.0.0 || ^11.0.0"
+      }
+    },
     "node_modules/@nestjs/jwt": {
       "version": "11.0.2",
       "resolved": "https://registry.npmmirror.com/@nestjs/jwt/-/jwt-11.0.2.tgz",
@@ -5972,6 +5986,12 @@
         "node": ">= 0.6"
       }
     },
+    "node_modules/eventemitter2": {
+      "version": "6.4.9",
+      "resolved": "https://registry.npmmirror.com/eventemitter2/-/eventemitter2-6.4.9.tgz",
+      "integrity": "sha512-JEPTiaOt9f04oa6NOkc4aH+nVp5I3wEjpHbIPqfgCdD5v5bUzy7xQqwcVO2aDQgOWhI28da57HksMrzK9HlRxg==",
+      "license": "MIT"
+    },
     "node_modules/events": {
       "version": "3.3.0",
       "resolved": "https://registry.npmmirror.com/events/-/events-3.3.0.tgz",

package.json

@@ -29,6 +29,7 @@
     "@nestjs/common": "^11.0.1",
     "@nestjs/config": "^4.0.4",
     "@nestjs/core": "^11.0.1",
+    "@nestjs/event-emitter": "^3.1.0",
     "@nestjs/jwt": "^11.0.2",
     "@nestjs/passport": "^11.0.5",
     "@nestjs/platform-express": "^11.0.1",

src/app.module.ts

@@ -6,6 +6,7 @@ import { JwtModule } from '@nestjs/jwt';
 import { PrismaModule } from './infrastructure/database/prisma.module';
 import { RedisModule } from './infrastructure/redis/redis.module';
 import { QueueModule } from './infrastructure/queue/queue.module';
+import { EventBusModule } from './common/event-bus/event-bus.module';
 import { AiModule } from './modules/ai/ai.module';
 import { StorageModule } from './infrastructure/storage/storage.module';
 import { LoggerModule } from './infrastructure/logger/logger.module';
@@ -85,6 +86,7 @@ import appleConfig from './config/apple.config';
     }),
     PrismaModule,
     RedisModule,
+    EventBusModule,
     QueueModule,
     AiModule,
     StorageModule,

src/common/event-bus/event-bus.module.ts

@@ -0,0 +1,17 @@
+import { Global, Module } from '@nestjs/common';
+import { EventEmitterModule } from '@nestjs/event-emitter';
+import { BullModule } from '@nestjs/bullmq';
+import { EventBusService } from './event-bus.service';
+
+export const QUEUE_DOMAIN_EVENTS = 'domain-events';
+
+@Global()
+@Module({
+  imports: [
+    EventEmitterModule.forRoot({ wildcard: true, delimiter: '.' }),
+    BullModule.registerQueue({ name: QUEUE_DOMAIN_EVENTS }),
+  ],
+  providers: [EventBusService],
+  exports: [EventBusService, EventEmitterModule],
+})
+export class EventBusModule {}

src/common/event-bus/event-bus.service.ts

@@ -0,0 +1,36 @@
+import { Injectable, Logger } from '@nestjs/common';
+import { EventEmitter2 } from '@nestjs/event-emitter';
+import { QueueService } from '../../infrastructure/queue/queue.service';
+import { BaseDomainEvent } from '../events/base-domain.event';
+import { safeLog } from '../../infrastructure/logger/sensitive-logger';
+
+export const DOMAIN_EVENT = 'domain.event';
+
+@Injectable()
+export class EventBusService {
+  private readonly logger = new Logger(EventBusService.name);
+
+  constructor(
+    private readonly eventEmitter: EventEmitter2,
+    private readonly queue: QueueService,
+  ) {}
+
+  /** Sync: process-in-memory, low latency, fire-and-forget */
+  publish(event: BaseDomainEvent): void {
+    this.logger.log(`[sync] ${event.eventType} id=${event.eventId}`);
+    this.eventEmitter.emit(DOMAIN_EVENT, event);
+    this.eventEmitter.emit(event.eventType, event);
+  }
+
+  /** Async: persistent via BullMQ, retry + DLQ */
+  async publishAsync(event: BaseDomainEvent): Promise<string> {
+    const job = await this.queue.add('domain-events', {
+      eventType: event.eventType,
+      eventId: event.eventId,
+      payload: safeLog(event),
+      occurredAt: event.occurredAt.toISOString(),
+    });
+    this.logger.log(`[async] ${event.eventType} id=${event.eventId} job=${job.id}`);
+    return job.id || '';
+  }
+}