✨ follow user

backend/src/main/java/net/pengcook/recipe/controller/RecipeController.java

@@ -61,6 +61,14 @@ public List<RecipeHomeWithMineResponseV1> readLikeRecipesV1(@LoginUser UserInfo
         return recipeService.readLikeRecipesV1(userInfo);
     }
 
+    @GetMapping("/follows")
+    public List<RecipeHomeWithMineResponseV1> readFollowRecipes(
+            @LoginUser UserInfo userInfo,
+            @ModelAttribute @Valid PageRecipeRequest pageRecipeRequest
+    ) {
+        return recipeService.readFollowRecipes(userInfo, pageRecipeRequest);
+    }
+
     @PostMapping
     @ResponseStatus(HttpStatus.CREATED)
     public RecipeResponse createRecipe(@LoginUser UserInfo userInfo, @RequestBody @Valid RecipeRequest recipeRequest) {

backend/src/main/java/net/pengcook/recipe/dto/RecipeHomeWithMineResponseV1.java

@@ -2,6 +2,7 @@
 
 import java.time.LocalDateTime;
 import net.pengcook.authentication.domain.UserInfo;
+import net.pengcook.recipe.domain.Recipe;
 
 public record RecipeHomeWithMineResponseV1(
         long recipeId,
@@ -29,4 +30,20 @@ public RecipeHomeWithMineResponseV1(
                 userInfo.isSameUser(firstResponse.authorId())
         );
     }
+
+    public RecipeHomeWithMineResponseV1(
+            UserInfo userInfo,
+            Recipe recipe
+    ) {
+        this(
+                recipe.getId(),
+                recipe.getTitle(),
+                new AuthorResponse(recipe.getAuthor()),
+                recipe.getThumbnail(),
+                recipe.getLikeCount(),
+                recipe.getCommentCount(),
+                recipe.getCreatedAt(),
+                userInfo.isSameUser(recipe.getAuthor().getId())
+        );
+    }
 }

backend/src/main/java/net/pengcook/recipe/repository/RecipeRepository.java

@@ -73,5 +73,7 @@ List<Long> findRecipeIdsByCategoryAndKeyword(
             """)
     List<Long> findRecipeIdsByUserId(long userId);
 
+    List<Recipe> findAllByAuthorIdIn(List<Long> authorIds, Pageable pageable);
+
     int countByAuthorId(long userId);
 }

backend/src/main/java/net/pengcook/recipe/service/RecipeService.java

@@ -29,6 +29,8 @@
 import net.pengcook.recipe.repository.RecipeRepository;
 import net.pengcook.recipe.repository.RecipeStepRepository;
 import net.pengcook.user.domain.User;
+import net.pengcook.user.domain.UserFollow;
+import net.pengcook.user.repository.UserFollowRepository;
 import net.pengcook.user.repository.UserRepository;
 import org.springframework.data.domain.PageRequest;
 import org.springframework.data.domain.Pageable;
@@ -46,6 +48,7 @@ public class RecipeService {
     private final UserRepository userRepository;
     private final RecipeLikeRepository likeRepository;
     private final RecipeStepRepository recipeStepRepository;
+    private final UserFollowRepository userFollowRepository;
 
     private final CategoryService categoryService;
     private final IngredientService ingredientService;
@@ -144,6 +147,22 @@ public List<RecipeHomeWithMineResponseV1> readLikeRecipesV1(UserInfo userInfo) {
                 .toList();
     }
 
+    @Transactional(readOnly = true)
+    public List<RecipeHomeWithMineResponseV1> readFollowRecipes(UserInfo userInfo,
+                                                                PageRecipeRequest pageRecipeRequest) {
+        List<UserFollow> followings = userFollowRepository.findAllByFollowerId(userInfo.getId());
+        List<Long> followeeIds = followings.stream()
+                .map(userFollow -> userFollow.getFollowee().getId())
+                .toList();
+        List<Recipe> recipes = recipeRepository.findAllByAuthorIdIn(followeeIds, pageRecipeRequest.getPageable());
+
+        return recipes.stream()
+                .map(recipe -> new RecipeHomeWithMineResponseV1(userInfo, recipe))
+                .sorted(Comparator.comparing(RecipeHomeWithMineResponseV1::recipeId).reversed())
+                .toList();
+    }
+
+
     @Transactional
     public RecipeResponse createRecipe(UserInfo userInfo, RecipeRequest recipeRequest) {
         User author = userRepository.findById(userInfo.getId()).orElseThrow();

backend/src/main/java/net/pengcook/user/controller/UserController.java

@@ -6,6 +6,7 @@
 import lombok.RequiredArgsConstructor;
 import net.pengcook.authentication.domain.UserInfo;
 import net.pengcook.authentication.resolver.LoginUser;
+import net.pengcook.user.dto.FollowInfoResponse;
 import net.pengcook.user.dto.ProfileResponse;
 import net.pengcook.user.dto.ReportReasonResponse;
 import net.pengcook.user.dto.ReportRequest;
@@ -14,7 +15,10 @@
 import net.pengcook.user.dto.UpdateProfileResponse;
 import net.pengcook.user.dto.UserBlockRequest;
 import net.pengcook.user.dto.UserBlockResponse;
+import net.pengcook.user.dto.UserFollowRequest;
+import net.pengcook.user.dto.UserFollowResponse;
 import net.pengcook.user.dto.UsernameCheckResponse;
+import net.pengcook.user.service.UserFollowService;
 import net.pengcook.user.service.UserService;
 import org.springframework.http.HttpStatus;
 import org.springframework.web.bind.annotation.DeleteMapping;
@@ -32,15 +36,16 @@
 public class UserController {
 
     private final UserService userService;
+    private final UserFollowService userFollowService;
 
     @GetMapping("/user/me")
     public ProfileResponse getUserProfile(@LoginUser UserInfo userInfo) {
-        return userService.getUserById(userInfo.getId());
+        return userService.getProfile(userInfo.getId(), userInfo.getId());
     }
 
     @GetMapping("/user/{userId}")
-    public ProfileResponse getUserProfile(@PathVariable long userId) {
-        return userService.getUserById(userId);
+    public ProfileResponse getUserProfile(@LoginUser UserInfo userInfo, @PathVariable long userId) {
+        return userService.getProfile(userInfo.getId(), userId);
     }
 
     @PatchMapping("/user/me")
@@ -84,4 +89,41 @@ public UserBlockResponse blockUser(
     ) {
         return userService.blockUser(userInfo.getId(), userBlockRequest.blockeeId());
     }
+
+    @PostMapping("/user/follow")
+    @ResponseStatus(HttpStatus.CREATED)
+    public UserFollowResponse followUser(
+            @LoginUser UserInfo userInfo,
+            @RequestBody @Valid UserFollowRequest userFollowRequest
+    ) {
+        return userFollowService.followUser(userInfo.getId(), userFollowRequest.targetId());
+    }
+
+    @DeleteMapping("/user/follow")
+    @ResponseStatus(HttpStatus.NO_CONTENT)
+    public void unfollowUser(
+            @LoginUser UserInfo userInfo,
+            @RequestBody @Valid UserFollowRequest userFollowRequest
+    ) {
+        userFollowService.unfollowUser(userInfo.getId(), userFollowRequest.targetId());
+    }
+
+    @DeleteMapping("/user/follower")
+    @ResponseStatus(HttpStatus.NO_CONTENT)
+    public void removeFollower(
+            @LoginUser UserInfo userInfo,
+            @RequestBody @Valid UserFollowRequest userFollowRequest
+    ) {
+        userFollowService.unfollowUser(userFollowRequest.targetId(), userInfo.getId());
+    }
+
+    @GetMapping("/user/{userId}/follower")
+    public FollowInfoResponse getFollowerInfo(@PathVariable long userId) {
+        return userFollowService.getFollowerInfo(userId);
+    }
+
+    @GetMapping("/user/{userId}/following")
+    public FollowInfoResponse getFollowingInfo(@PathVariable long userId) {
+        return userFollowService.getFollowingInfo(userId);
+    }
 }

backend/src/main/java/net/pengcook/user/domain/User.java

@@ -11,6 +11,7 @@
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
 import lombok.NoArgsConstructor;
+import org.hibernate.annotations.ColumnDefault;
 
 @Entity
 @Table(name = "users")
@@ -39,8 +40,22 @@ public class User {
     @Column(nullable = false)
     private String region;
 
-    public User(String email, String username, String nickname, String image, String region) {
-        this(0L, email, username, nickname, image, region);
+    @Column(nullable = false)
+    @ColumnDefault("0")
+    private long followerCount;
+
+    @Column(nullable = false)
+    @ColumnDefault("0")
+    private long followeeCount;
+
+    public User(
+            String email,
+            String username,
+            String nickname,
+            String image,
+            String region
+    ) {
+        this(0L, email, username, nickname, image, region, 0, 0);
     }
 
     public boolean isSameUser(long userId) {
@@ -53,4 +68,20 @@ public void update(String username, String nickname, String image, String region
         this.image = image;
         this.region = region;
     }
+
+    public void increaseFollowerCount() {
+        followerCount++;
+    }
+
+    public void decreaseFollowerCount() {
+        followerCount--;
+    }
+
+    public void increaseFolloweeCount() {
+        followeeCount++;
+    }
+
+    public void decreaseFolloweeCount() {
+        followeeCount--;
+    }
 }

backend/src/main/java/net/pengcook/user/domain/UserFollow.java

@@ -0,0 +1,47 @@
+package net.pengcook.user.domain;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.Table;
+import jakarta.persistence.UniqueConstraint;
+import lombok.AccessLevel;
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import net.pengcook.user.exception.BadArgumentException;
+
+@Entity
+@Table(uniqueConstraints = {@UniqueConstraint(columnNames = {"follower_id", "followee_id"})})
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@EqualsAndHashCode(of = "id")
+@Getter
+public class UserFollow {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private long id;
+
+    @ManyToOne
+    @JoinColumn(name = "follower_id")
+    private User follower;
+
+    @ManyToOne
+    @JoinColumn(name = "followee_id")
+    private User followee;
+
+    public UserFollow(User follower, User followee) {
+        validate(follower, followee);
+        this.follower = follower;
+        this.followee = followee;
+    }
+
+    private void validate(User follower, User followee) {
+        if (follower.equals(followee)) {
+            throw new BadArgumentException("자기 자신을 팔로우할 수 없습니다.");
+        }
+    }
+}

backend/src/main/java/net/pengcook/user/dto/FollowInfoResponse.java

@@ -0,0 +1,12 @@
+package net.pengcook.user.dto;
+
+import java.util.List;
+
+public record FollowInfoResponse(
+        List<FollowUserInfoResponse> follows,
+        long followCount
+) {
+    public FollowInfoResponse(List<FollowUserInfoResponse> follows) {
+        this(follows, follows.size());
+    }
+}

backend/src/main/java/net/pengcook/user/dto/FollowUserInfoResponse.java

@@ -0,0 +1,10 @@
+package net.pengcook.user.dto;
+
+import net.pengcook.user.domain.User;
+
+public record FollowUserInfoResponse(String username, String image) {
+
+    public FollowUserInfoResponse(User user) {
+        this(user.getUsername(), user.getImage());
+    }
+}

backend/src/main/java/net/pengcook/user/dto/ProfileResponse.java

@@ -10,12 +10,13 @@ public record ProfileResponse(
         String image,
         String region,
         String introduction,
-        long follower,
-        long following,
-        long recipeCount
+        long followerCount,
+        long followingCount,
+        long recipeCount,
+        boolean isFollow
 ) {
 
-    public ProfileResponse(User user, long recipeCount) {
+    public ProfileResponse(User user, long recipeCount, boolean isFollow) {
         this(
                 user.getId(),
                 user.getEmail(),
@@ -24,9 +25,10 @@ public ProfileResponse(User user, long recipeCount) {
                 user.getImage(),
                 user.getRegion(),
                 "hello world",
-                0,
-                0,
-                recipeCount
+                user.getFollowerCount(),
+                user.getFolloweeCount(),
+                recipeCount,
+                isFollow
         );
     }
 }

backend/src/main/java/net/pengcook/user/dto/UserFollowRequest.java

@@ -0,0 +1,6 @@
+package net.pengcook.user.dto;
+
+import jakarta.validation.constraints.NotNull;
+
+public record UserFollowRequest(@NotNull long targetId) {
+}

backend/src/main/java/net/pengcook/user/dto/UserFollowResponse.java

@@ -0,0 +1,15 @@
+package net.pengcook.user.dto;
+
+import net.pengcook.user.domain.UserFollow;
+
+public record UserFollowResponse(
+        long followerId,
+        long followeeId
+) {
+    public UserFollowResponse(UserFollow userFollow) {
+        this(
+                userFollow.getFollower().getId(),
+                userFollow.getFollowee().getId()
+        );
+    }
+}

backend/src/main/java/net/pengcook/user/exception/IllegalStateException.java

@@ -0,0 +1,10 @@
+package net.pengcook.user.exception;
+
+import org.springframework.http.HttpStatus;
+
+public class IllegalStateException extends UserException {
+
+    public IllegalStateException(String message) {
+        super(HttpStatus.FORBIDDEN, message);
+    }
+}

backend/src/main/java/net/pengcook/user/repository/UserBlockRepository.java

@@ -12,4 +12,6 @@ public interface UserBlockRepository extends JpaRepository<UserBlock, Long> {
     void deleteByBlockeeId(long blockeeId);
 
     void deleteByBlockerId(long blockerId);
+
+    boolean existsByBlockerIdAndBlockeeId(long blockerId, long blockeeId);
 }

backend/src/main/java/net/pengcook/user/repository/UserFollowRepository.java

@@ -0,0 +1,17 @@
+package net.pengcook.user.repository;
+
+import java.util.List;
+import java.util.Optional;
+import net.pengcook.user.domain.UserFollow;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+public interface UserFollowRepository extends JpaRepository<UserFollow, Long> {
+
+    Optional<UserFollow> findByFollowerIdAndFolloweeId(Long followerId, Long followeeId);
+
+    List<UserFollow> findAllByFollowerId(long followerId);
+
+    List<UserFollow> findAllByFolloweeId(long followeeId);
+
+    boolean existsByFollowerIdAndFolloweeId(long followerId, long followeeId);
+}