feat : 5주차 과제

apps/commerce-api/src/main/java/com/loopers/application/favorite/FavoriteFacade.java

@@ -24,7 +24,10 @@ public void addFavorite(String loginId, String password, Long productId) {
         Member member = memberService.findMember(loginId, password);
         Product product = productService.findProduct(productId);
         FavoriteCommand.Add command = new FavoriteCommand.Add(member.getId(), product.getId());
-        favoriteService.addFavorite(command);
+        boolean added = favoriteService.addFavorite(command);
+        if (added) {
+            productService.increaseLikeCount(product.getId());
+        }
     }
 
     @Transactional(rollbackFor = {Exception.class})
@@ -33,5 +36,6 @@ public void deleteFavorite(String loginId, String password, Long productId) {
         Product product = productService.findProduct(productId);
         FavoriteCommand.Delete command = new FavoriteCommand.Delete(member.getId(), product.getId());
         favoriteService.delete(command);
+        productService.decreaseLikeCount(product.getId());
     }
 }

apps/commerce-api/src/main/java/com/loopers/application/product/ProductFacade.java

@@ -1,50 +1,54 @@
 package com.loopers.application.product;
 
+import com.loopers.application.product.dto.FindProductListReqDto;
 import com.loopers.application.product.dto.FindProductListResDto;
 import com.loopers.application.product.dto.FindProductResDto;
-import com.loopers.domain.brand.model.Brand;
 import com.loopers.domain.brand.service.BrandService;
 import com.loopers.domain.favorite.service.FavoriteService;
 import com.loopers.domain.member.model.Member;
 import com.loopers.domain.member.service.MemberService;
-import com.loopers.domain.product.model.Product;
 import com.loopers.domain.product.model.ProductItem;
 import com.loopers.domain.product.service.ProductService;
-import com.loopers.support.enums.SortFilter;
 import lombok.RequiredArgsConstructor;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.stereotype.Component;
 import org.springframework.transaction.annotation.Transactional;
 
+import java.util.List;
+import java.util.Set;
+
 @RequiredArgsConstructor
 @Component
 @Transactional(readOnly = true)
 public class ProductFacade {
 
     private final ProductService productService;
     private final BrandService brandService;
-    private final FavoriteService favoriteService;
     private final MemberService memberService;
+    private final FavoriteService favoriteService;
 
-    public Page<FindProductListResDto> findProductList(String loginId, String password, Long brandId, SortFilter sortFilter, Pageable pageable) {
-        if (brandId != null) {
-            brandService.findBrand(brandId);
+    public Page<FindProductListResDto> findProductList(FindProductListReqDto req, Pageable pageable) {
+        if (req.brandId() != null) {
+            brandService.findBrand(req.brandId());
         }
-        Long memberId = resolveMemberId(loginId, password);
-        Page<ProductItem> items = productService.findProductList(brandId, memberId, sortFilter, pageable);
-        return items.map(FindProductListResDto::from);
+        Long memberId = resolveMemberId(req.loginId(), req.password());
+
+        Page<ProductItem> products = productService.findProductList(req.brandId(), req.sortFilter(), pageable);
+        List<Long> productIds = products.getContent().stream().map(ProductItem::id).toList();
+        Set<Long> favoriteIds = favoriteService.getFavoriteProductIds(memberId, productIds);
+
+        return products.map(item -> FindProductListResDto.from(
+                item.withIsFavorite(favoriteIds.contains(item.id()))
+        ));
     }
 
     public FindProductResDto findProduct(String loginId, String password, Long productId) {
-        Product product = productService.findProduct(productId);
-        Brand brand = brandService.findBrand(product.getBrandId());
-
-        long favoriteCnt = favoriteService.countByProductId(productId);
         Long memberId = resolveMemberId(loginId, password);
-        boolean isFavorite = memberId != null && favoriteService.existsByMemberIdAndProductId(memberId, productId);
-
-        return FindProductResDto.of(product, brand, favoriteCnt, isFavorite);
+        ProductItem item = productService.findProductDetail(productId);
+        boolean isFavorite = memberId != null
+                && favoriteService.existsByMemberIdAndProductId(memberId, productId);
+        return FindProductResDto.from(item.withIsFavorite(isFavorite));
     }
 
     private Long resolveMemberId(String loginId, String password) {

apps/commerce-api/src/main/java/com/loopers/application/product/dto/FindProductListReqDto.java

@@ -0,0 +1,11 @@
+package com.loopers.application.product.dto;
+
+import com.loopers.support.enums.SortFilter;
+
+public record FindProductListReqDto(
+        String loginId,
+        String password,
+        Long brandId,
+        SortFilter sortFilter
+) {
+}

apps/commerce-api/src/main/java/com/loopers/application/product/dto/FindProductResDto.java

@@ -1,7 +1,6 @@
 package com.loopers.application.product.dto;
 
-import com.loopers.domain.brand.model.Brand;
-import com.loopers.domain.product.model.Product;
+import com.loopers.domain.product.model.ProductItem;
 
 public record FindProductResDto(
         Long id,
@@ -14,17 +13,17 @@ public record FindProductResDto(
         long favoriteCnt,
         boolean isFavorite
 ) {
-    public static FindProductResDto of(Product product, Brand brand, long favoriteCnt, boolean isFavorite) {
+    public static FindProductResDto from(ProductItem item) {
         return new FindProductResDto(
-                product.getId(),
-                product.getName().value(),
-                brand.getId(),
-                brand.getName().value(),
-                product.getPrice().value(),
-                product.getStock().value(),
-                product.getDisplayStatus().name(),
-                favoriteCnt,
-                isFavorite
+                item.id(),
+                item.name(),
+                item.brandId(),
+                item.brandName(),
+                item.price(),
+                item.stock(),
+                item.displayStatus(),
+                item.favoriteCnt(),
+                item.isFavorite()
         );
     }
 }

apps/commerce-api/src/main/java/com/loopers/domain/favorite/repository/FavoriteRepository.java

@@ -2,6 +2,7 @@
 
 import com.loopers.domain.favorite.model.Favorite;
 
+import java.util.List;
 import java.util.Optional;
 
 public interface FavoriteRepository {
@@ -10,6 +11,8 @@ public interface FavoriteRepository {
 
     Optional<Favorite> findByMemberIdAndProductId(Long memberId, Long productId);
 
+    List<Favorite> findByMemberIdAndProductIds(Long memberId, List<Long> productIds);
+
     void delete(Favorite favorite);
 
     boolean existsByMemberIdAndProductId(Long memberId, Long productId);

apps/commerce-api/src/main/java/com/loopers/domain/favorite/service/FavoriteService.java

@@ -6,24 +6,33 @@
 import com.loopers.support.error.CoreException;
 import com.loopers.support.error.ErrorType;
 import lombok.RequiredArgsConstructor;
+import org.hibernate.exception.ConstraintViolationException;
 import org.springframework.dao.DataIntegrityViolationException;
 import org.springframework.stereotype.Component;
 
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+
 @RequiredArgsConstructor
 @Component
 public class FavoriteService {
 
     private final FavoriteRepository favoriteRepository;
 
-    public void addFavorite(FavoriteCommand.Add command) {
+    public boolean addFavorite(FavoriteCommand.Add command) {
         if (favoriteRepository.existsByMemberIdAndProductId(command.memberId(), command.productId())) {
-            return;
+            return false;
         }
         try {
             Favorite favorite = Favorite.create(command.memberId(), command.productId());
             favoriteRepository.save(favorite);
+            return true;
         } catch (DataIntegrityViolationException e) {
-            // 동시 요청으로 중복 등록 시도 — 이미 등록된 것이므로 무시
+            if (e.getCause() instanceof ConstraintViolationException) {
+                return false;
+            }
+            throw e;
         }
     }
 
@@ -40,4 +49,14 @@ public boolean existsByMemberIdAndProductId(Long memberId, Long productId) {
     public long countByProductId(Long productId) {
         return favoriteRepository.countByProductId(productId);
     }
+
+    public Set<Long> getFavoriteProductIds(Long memberId, List<Long> productIds) {
+        if (memberId == null || productIds == null || productIds.isEmpty()) {
+            return Set.of();
+        }
+        return favoriteRepository.findByMemberIdAndProductIds(memberId, productIds)
+            .stream()
+            .map(Favorite::getProductId)
+            .collect(Collectors.toSet());
+    }
 }

apps/commerce-api/src/main/java/com/loopers/domain/product/model/Product.java

@@ -15,13 +15,15 @@ public class Product {
     private Money price;
     private Stock stock;
     private DisplayStatus displayStatus;
+    private long likeCount;
 
     private Product(Long brandId, ProductName name, Money price, Stock stock, DisplayStatus displayStatus) {
         this.brandId = brandId;
         this.name = name;
         this.price = price;
         this.stock = stock;
         this.displayStatus = displayStatus;
+        this.likeCount = 0;
     }
 
     public static Product create(Long brandId, ProductCommand.Create command) {
@@ -34,7 +36,7 @@ public static Product create(Long brandId, ProductCommand.Create command) {
         );
     }
 
-    public static Product reconstruct(Long id, Long brandId, String name, int price, int stock, DisplayStatus displayStatus) {
+    public static Product reconstruct(Long id, Long brandId, String name, int price, int stock, DisplayStatus displayStatus, long likeCount) {
         Product product = new Product(
                 brandId,
                 new ProductName(name),
@@ -43,6 +45,7 @@ public static Product reconstruct(Long id, Long brandId, String name, int price,
                 displayStatus
         );
         product.id = id;
+        product.likeCount = likeCount;
         return product;
     }
 

apps/commerce-api/src/main/java/com/loopers/domain/product/model/ProductItem.java

@@ -10,4 +10,12 @@ public record ProductItem(
         String displayStatus,
         long favoriteCnt,
         boolean isFavorite
-) {}
+) {
+    public ProductItem withIsFavorite(boolean isFavorite) {
+        return new ProductItem(id, name, brandId, brandName, price, stock, displayStatus, favoriteCnt, isFavorite);
+    }
+
+    public ProductItem withFavoriteCnt(long favoriteCnt) {
+        return new ProductItem(id, name, brandId, brandName, price, stock, displayStatus, favoriteCnt, isFavorite);
+    }
+}

apps/commerce-api/src/main/java/com/loopers/domain/product/repository/ProductCacheRepository.java

@@ -0,0 +1,31 @@
+package com.loopers.domain.product.repository;
+
+import com.loopers.domain.product.model.ProductItem;
+
+import java.util.List;
+import java.util.Optional;
+
+public interface ProductCacheRepository {
+
+    Optional<ProductItem> get(Long productId);
+
+    void put(Long productId, ProductItem item);
+
+    void evict(Long productId);
+
+    record CachedPage(List<ProductItem> items, long totalElements) {}
+
+    Optional<CachedPage> getFirstPage();
+
+    void putFirstPage(List<ProductItem> items, long totalElements);
+
+    void evictFirstPage();
+
+    Optional<Long> getLikeCount(Long productId);
+
+    void initLikeCountIfAbsent(Long productId, long count);
+
+    void incrementLikeCount(Long productId);
+
+    void decrementLikeCount(Long productId);
+}

apps/commerce-api/src/main/java/com/loopers/domain/product/repository/ProductCustomRepository.java

@@ -1,6 +1,5 @@
 package com.loopers.domain.product.repository;
 
-import com.loopers.domain.product.model.ProductItem;
 import com.loopers.domain.product.model.ProductItem;
 import com.loopers.support.enums.SortFilter;
 import org.springframework.data.domain.Page;
@@ -10,6 +9,6 @@
 
 public interface ProductCustomRepository {
 
-    Page<ProductItem> findProductList(Long brandId, Long memberId, SortFilter sortFilter, Pageable pageable);
-    Optional<ProductItem> findProduct(Long productId, Long memberId);
+    Page<ProductItem> findProductList(Long brandId, SortFilter sortFilter, Pageable pageable);
+    Optional<ProductItem> findProduct(Long productId);
 }

apps/commerce-api/src/main/java/com/loopers/domain/product/repository/ProductRepository.java

@@ -24,4 +24,8 @@ public interface ProductRepository {
     List<Product> findByIds(List<Long> ids);
 
     int decreaseStock(Long id, int quantity);
+
+    int increaseLikeCount(Long id);
+
+    int decreaseLikeCount(Long id);
 }