feature: ProductStockEvent에 가격 필드 추가 및 주문 이벤트 처리 개선

- ProductStockEvent에 가격(price) 필드 추가로 이벤트 정보 확장
- OrderCreatedEvent에서 상품과 가격 데이터를 함께 매핑하도록 수정
- OrderSalesAggregateListener에서 이벤트 발행 시 가격 정보를 관리하도록 개선

Author: yeonjiyeon

apps/commerce-api/src/main/java/com/loopers/application/order/event/OrderCreatedEvent.java

@@ -7,6 +7,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.UUID;
+import java.util.function.Function;
 import java.util.stream.Collectors;
 
 public record OrderCreatedEvent(
@@ -21,7 +22,7 @@ public record OrderCreatedEvent(
     Long couponId
 ) {
 
-  public record OrderItemInfo(Long productId, int quantity, int remainStock) {
+  public record OrderItemInfo(Long productId, int quantity, long price, int remainStock) {
 
   }
 
@@ -37,15 +38,19 @@ public static OrderCreatedEvent of(
       Long couponId
   ) {
 
-    Map<Long, Integer> stockMap = products.stream()
-        .collect(Collectors.toMap(Product::getId, Product::getStock));
+    Map<Long, Product> productMap = products.stream()
+        .collect(Collectors.toMap(Product::getId, p -> p));
 
     List<OrderItemInfo> itemInfos = orderItems.stream()
-        .map(item -> new OrderItemInfo(
-            item.getProductId(),
-            item.getQuantity(),
-            stockMap.getOrDefault(item.getProductId(), 0)
-            )).toList();
+        .map(item -> {
+          Product product = productMap.get(item.getProductId());
+          return new OrderItemInfo(
+              item.getProductId(),
+              item.getQuantity(),
+              product != null ? product.getPrice().getValue() : 0,
+              product != null ? product.getStock() : 0
+          );
+        }).toList();
 
     return new OrderCreatedEvent(
         UUID.randomUUID().toString(),

apps/commerce-api/src/main/java/com/loopers/application/order/event/OrderSalesAggregateListener.java

@@ -1,7 +1,6 @@
 package com.loopers.application.order.event;
 
 import com.loopers.domain.event.OutboxService;
-import com.loopers.domain.product.ProductService;
 import com.loopers.event.ProductStockEvent;
 import lombok.RequiredArgsConstructor;
 import org.springframework.context.ApplicationEventPublisher;
@@ -26,7 +25,8 @@ public void handleOrderCreated(OrderCreatedEvent event) {
       ProductStockEvent kafkaEvent = ProductStockEvent.of(
           item.productId(),
           item.quantity(),
-          item.remainStock()
+          item.remainStock(),
+          item.price()
       );
 
       outboxService.saveEvent("STOCKS_METRICS", String.valueOf(item.productId()), kafkaEvent);

apps/commerce-streamer/src/main/java/com/loopers/interfaces/consumer/MetricsEventConsumer.java

@@ -1,6 +1,7 @@
 package com.loopers.interfaces.consumer;
 
 import com.loopers.domain.metrics.ProductMetricsService;
+import com.loopers.domain.rank.RankingService;
 import com.loopers.event.LikeCountEvent;
 import com.loopers.event.ProductStockEvent;
 import com.loopers.event.ProductViewEvent;
@@ -17,6 +18,7 @@
 public class MetricsEventConsumer {
 
   private final ProductMetricsService metricsService;
+  private final RankingService rankingService;
 
   @KafkaListener(
       topics = "catalog-events",

modules/kafka/src/main/java/com/loopers/event/ProductStockEvent.java

@@ -7,14 +7,16 @@ public record ProductStockEvent(
     Long productId,
     int sellQuantity,
     int currentStock,
+    long price,
     long timestamp
 ) {
-  public static ProductStockEvent of(Long productId, int sellQuantity, int currentStock) {
+  public static ProductStockEvent of(Long productId, int sellQuantity, int currentStock, long price) {
     return new ProductStockEvent(
         UUID.randomUUID().toString(),
         productId,
         sellQuantity,
         currentStock,
+        price,
         System.currentTimeMillis()
     );
   }