[Feat]: 친구 리스트 조회 API 구현

src/main/java/io/sobok/SobokSobok/exception/SuccessCode.java

@@ -26,6 +26,7 @@ public enum SuccessCode {
 
     // friend
     ADD_FRIEND_SUCCESS(HttpStatus.OK, "공유 요청에 성공했습니다."),
+    GET_FRIEND_LIST_SUCCESS(HttpStatus.OK, "친구 리스트 조회에 성공했습니다."),
     HANDLE_FRIEND_REQUEST_SUCCESS(HttpStatus.OK, "공유 응답에 성공했습니다."),
 
     // notice

src/main/java/io/sobok/SobokSobok/friend/application/FriendService.java

@@ -13,6 +13,7 @@
 import io.sobok.SobokSobok.friend.infrastructure.SendFriendRepository;
 import io.sobok.SobokSobok.friend.ui.dto.AddFriendRequest;
 import io.sobok.SobokSobok.friend.ui.dto.AddFriendResponse;
+import io.sobok.SobokSobok.friend.ui.dto.FriendListResponse;
 import io.sobok.SobokSobok.friend.ui.dto.HandleFriendRequest;
 import io.sobok.SobokSobok.friend.ui.dto.HandleFriendRequestResponse;
 import io.sobok.SobokSobok.notice.domain.Notice;
@@ -21,6 +22,8 @@
 import io.sobok.SobokSobok.notice.infrastructure.NoticeQueryRepository;
 import io.sobok.SobokSobok.notice.infrastructure.NoticeRepository;
 import java.time.LocalDateTime;
+import java.util.List;
+import java.util.stream.Collectors;
 import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
@@ -80,6 +83,20 @@ public AddFriendResponse addFriend(Long userId, AddFriendRequest request) {
             .build();
     }
 
+    @Transactional(readOnly = true)
+    public List<FriendListResponse> getFriendList(Long userId) {
+        UserServiceUtil.existsUserById(userRepository, userId);
+
+        return friendRepository.findAllBySenderId(userId)
+            .stream().map(friend ->
+                FriendListResponse.builder()
+                    .friendId(friend.getId())
+                    .memberId(friend.getReceiverId())
+                    .friendName(friend.getFriendName())
+                    .build()
+            ).collect(Collectors.toList());
+    }
+
     @Transactional(noRollbackFor = {ConflictException.class})
     public HandleFriendRequestResponse updateNoticeStatus(Long userId, Long noticeId,
         HandleFriendRequest request) {

src/main/java/io/sobok/SobokSobok/friend/infrastructure/FriendRepository.java

@@ -1,9 +1,12 @@
 package io.sobok.SobokSobok.friend.infrastructure;
 
 import io.sobok.SobokSobok.friend.domain.Friend;
+import java.util.List;
 import org.springframework.data.jpa.repository.JpaRepository;
 
 public interface FriendRepository extends JpaRepository<Friend, Long> {
 
+    List<Friend> findAllBySenderId(Long senderId);
+
     Integer countBySenderId(Long senderId);
 }

src/main/java/io/sobok/SobokSobok/friend/ui/FriendController.java

@@ -6,15 +6,18 @@
 import io.sobok.SobokSobok.friend.application.FriendService;
 import io.sobok.SobokSobok.friend.ui.dto.AddFriendRequest;
 import io.sobok.SobokSobok.friend.ui.dto.AddFriendResponse;
+import io.sobok.SobokSobok.friend.ui.dto.FriendListResponse;
 import io.sobok.SobokSobok.friend.ui.dto.HandleFriendRequest;
 import io.sobok.SobokSobok.friend.ui.dto.HandleFriendRequestResponse;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 import jakarta.validation.Valid;
+import java.util.List;
 import lombok.RequiredArgsConstructor;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.security.core.annotation.AuthenticationPrincipal;
+import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.PutMapping;
@@ -64,4 +67,20 @@ public ResponseEntity<ApiResponse<HandleFriendRequestResponse>> handleFriendRequ
                 friendService.updateNoticeStatus(user.getId(), noticeId, request)
             ));
     }
+
+    @GetMapping("")
+    @Operation(
+        summary = "친구 리스트 조회 API 메서드",
+        description = "친구 리스트를 조회하는 메서드입니다."
+    )
+    public ResponseEntity<ApiResponse<List<FriendListResponse>>> getFriendList(
+        @AuthenticationPrincipal User user
+    ) {
+        return ResponseEntity
+            .status(HttpStatus.OK)
+            .body(ApiResponse.success(
+                SuccessCode.GET_FRIEND_LIST_SUCCESS,
+                friendService.getFriendList(user.getId())
+            ));
+    }
 }

src/main/java/io/sobok/SobokSobok/friend/ui/dto/FriendListResponse.java

@@ -0,0 +1,12 @@
+package io.sobok.SobokSobok.friend.ui.dto;
+
+import lombok.Builder;
+
+@Builder
+public record FriendListResponse(
+    Long friendId,
+    Long memberId,
+    String friendName
+) {
+
+}