Feat: [FN-307] 그룹 내 유저 조회 API 추가

src/main/java/flipnote/group/adapter/in/web/GroupController.java

@@ -15,6 +15,7 @@
 import flipnote.group.api.dto.request.CreateGroupRequestDto;
 import flipnote.group.api.dto.response.ChangeGroupResponseDto;
 import flipnote.group.api.dto.response.CreateGroupResponseDto;
+import flipnote.group.api.dto.response.FindGroupMemberResponseDto;
 import flipnote.group.api.dto.response.FindGroupResponseDto;
 import flipnote.group.application.port.in.ChangeGroupUseCase;
 import flipnote.group.application.port.in.CreateGroupUseCase;
@@ -24,6 +25,7 @@
 import flipnote.group.application.port.in.command.CreateGroupCommand;
 import flipnote.group.application.port.in.command.DeleteGroupCommand;
 import flipnote.group.application.port.in.command.FindGroupCommand;
+import flipnote.group.application.port.in.command.FindGroupMemberCommand;
 import jakarta.validation.Valid;
 import lombok.RequiredArgsConstructor;
 
@@ -125,24 +127,20 @@ public ResponseEntity<FindGroupResponseDto> findGroup(
 	@DeleteMapping("/{groupId}")
 	public ResponseEntity<Void> deleteGroup(
 		@RequestHeader("X-USER-ID") Long userId,
-		@PathVariable("groupId") Long groupId
-	) {
+		@PathVariable("groupId") Long groupId) {
 
 		DeleteGroupCommand cmd = new DeleteGroupCommand(userId, groupId);
 
 		deleteGroupUseCase.deleteGroup(cmd);
 
 		return ResponseEntity.noContent().build();
 	}
-
-	//todo 그룹 내 멤버 조회
 
 	//todo 그룹 전체 조회
 
 	//todo 내 그룹 전체 조회
 
 	//todo 내가 생성한 그룹 전체 조회
 
-	//todo 하위 권한 수정
 
 }

src/main/java/flipnote/group/adapter/in/web/InvitationController.java

@@ -0,0 +1,18 @@
+package flipnote.group.adapter.in.web;
+
+public class InvitationController {
+	//todo 가인 신청 요청
+
+	//todo 그룹 내 가입 신청한 리스트 조회
+
+	//todo 가입신청 응답
+
+	//todo 가입신청 삭제
+
+	//todo 내가 신청한 가입신청 리스트 조회
+
+	//todo 초대
+
+	//todo 그룹 멤버 추방
+
+}

src/main/java/flipnote/group/adapter/in/web/MemberController.java

@@ -1,18 +1,44 @@
 package flipnote.group.adapter.in.web;
 
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestHeader;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import flipnote.group.api.dto.response.FindGroupMemberResponseDto;
+import flipnote.group.application.port.in.FindGroupMemberUseCase;
+import flipnote.group.application.port.in.command.FindGroupMemberCommand;
+import flipnote.group.application.port.in.result.FindGroupMemberResult;
+import lombok.RequiredArgsConstructor;
+
+@RequiredArgsConstructor
+@RestController
+@RequestMapping("/v1/groups/{groupId}")
 public class MemberController {
-	//todo 가인 신청 요청
-
-	//todo 그룹 내 가입 신청한 리스트 조회
-
-	//todo 가입신청 응답
-
-	//todo 가입신청 삭제
-
-	//todo 내가 신청한 가입신청 리스트 조회
 
-	//todo 초대
+	private final FindGroupMemberUseCase findGroupMemberUseCase;
+
+	/**
+	 * 그룹 내 멤버 전체 조회
+	 * @param userId
+	 * @param groupId
+	 * @return
+	 */
+	@GetMapping("/members")
+	public ResponseEntity<FindGroupMemberResponseDto> findGroupMembers(
+		@RequestHeader("X-USER-ID") Long userId,
+		@PathVariable("groupId") Long groupId) {
+
+		FindGroupMemberCommand cmd = new FindGroupMemberCommand(userId, groupId);
+
+		FindGroupMemberResult result = findGroupMemberUseCase.findGroupMember(cmd);
+
+		FindGroupMemberResponseDto res = FindGroupMemberResponseDto.from(result);
 
-	//todo 그룹 멤버 추방
+		return ResponseEntity.ok(res);
+	}
 
+	//todo 하위 권한 수정
 }

src/main/java/flipnote/group/adapter/out/entity/GroupMemberEntity.java

@@ -6,9 +6,12 @@
 import jakarta.persistence.Entity;
 import jakarta.persistence.EnumType;
 import jakarta.persistence.Enumerated;
+import jakarta.persistence.FetchType;
 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;
@@ -40,14 +43,15 @@ public class GroupMemberEntity extends BaseEntity {
 	@Column(name = "user_id", nullable = false)
 	private Long userId;
 
-	@Column(name = "group_role_id", nullable = false)
-	private Long groupRoleId;
+	@ManyToOne(fetch = FetchType.LAZY)
+	@JoinColumn(name = "group_role_id", nullable = false)
+	private RoleEntity role;
 
 	@Builder
-	private GroupMemberEntity(Long groupId, Long userId, Long groupRoleId) {
+	private GroupMemberEntity(Long groupId, Long userId, RoleEntity role) {
 		this.groupId = groupId;
 		this.userId = userId;
-		this.groupRoleId = groupRoleId;
+		this.role = role;
 	}
 
 	/**
@@ -56,11 +60,11 @@ private GroupMemberEntity(Long groupId, Long userId, Long groupRoleId) {
 	 * @param userId
 	 * @return
 	 */
-	public static GroupMemberEntity create(Long groupId, Long userId, Long groupRoleId) {
+	public static GroupMemberEntity create(Long groupId, Long userId, RoleEntity role) {
 		return GroupMemberEntity.builder()
 			.groupId(groupId)
 			.userId(userId)
-			.groupRoleId(groupRoleId)
+			.role(role)
 			.build();
 	}
 }

src/main/java/flipnote/group/adapter/out/persistence/GroupMemberRepositoryAdapter.java

@@ -1,27 +1,32 @@
 package flipnote.group.adapter.out.persistence;
 
+import java.util.List;
+
 import org.springframework.stereotype.Repository;
 
+import flipnote.group.adapter.out.entity.GroupMemberEntity;
+import flipnote.group.adapter.out.entity.RoleEntity;
 import flipnote.group.adapter.out.persistence.mapper.GroupMemberMapper;
 import flipnote.group.application.port.out.GroupMemberRepositoryPort;
-import flipnote.group.domain.model.member.GroupMemberRole;
-import flipnote.group.infrastructure.persistence.jpa.GroupMemberRepository;
+import flipnote.group.domain.model.member.GroupMember;
+import flipnote.group.domain.model.member.MemberInfo;
+import flipnote.group.infrastructure.persistence.jpa.GroupMemberRepositoryRepository;
 import lombok.RequiredArgsConstructor;
 
 @Repository
 @RequiredArgsConstructor
 public class GroupMemberRepositoryAdapter implements GroupMemberRepositoryPort {
 
-	private final GroupMemberRepository groupMemberRepository;
+	private final GroupMemberRepositoryRepository groupMemberRepository;
 
 	/**
 	 * 그룹 멤버 저장
 	 * @param groupId
 	 * @param userId
 	 */
 	@Override
-	public void save(Long groupId, Long userId, Long roleId) {
-		groupMemberRepository.save(GroupMemberMapper.create(groupId, userId, roleId));
+	public void save(Long groupId, Long userId, RoleEntity role) {
+		groupMemberRepository.save(GroupMemberMapper.create(groupId, userId, role));
 	}
 
 	/**
@@ -31,7 +36,26 @@ public void save(Long groupId, Long userId, Long roleId) {
 	 * @return
 	 */
 	@Override
-	public boolean existsUserInGroup(Long groupId, Long userId) {
-		return groupMemberRepository.existsByGroupIdAndUserId(groupId, userId);
+	public void existsUserInGroup(Long groupId, Long userId) {
+
+		boolean isMember = groupMemberRepository.existsByGroupIdAndUserId(groupId, userId);
+
+		if(!isMember) {
+			throw new IllegalArgumentException("user not in Group");
+		}
+	}
+
+	/**
+	 * 그룹 멤버 아이디 조회
+	 * @param groupId
+	 * @return
+	 */
+	@Override
+	public List<MemberInfo> findMemberInfo(Long groupId) {
+		List<GroupMemberEntity> entities = groupMemberRepository.findAllByGroupId(groupId);
+
+		List<MemberInfo> memberInfo = GroupMemberMapper.toMemberInfo(entities);
+
+		return memberInfo;
 	}
 }

src/main/java/flipnote/group/adapter/out/persistence/GroupRoleRepositoryAdapter.java

@@ -3,6 +3,7 @@
 import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
+import java.util.stream.Collectors;
 
 import org.springframework.stereotype.Repository;
 
@@ -11,7 +12,7 @@
 import flipnote.group.application.port.out.GroupRoleRepositoryPort;
 import flipnote.group.domain.model.member.GroupMemberRole;
 import flipnote.group.domain.model.permission.GroupPermission;
-import flipnote.group.infrastructure.persistence.jpa.GroupMemberRepository;
+import flipnote.group.infrastructure.persistence.jpa.GroupMemberRepositoryRepository;
 import flipnote.group.infrastructure.persistence.jpa.GroupRolePermissionRepository;
 import flipnote.group.infrastructure.persistence.jpa.GroupRoleRepository;
 import lombok.RequiredArgsConstructor;
@@ -22,7 +23,7 @@ public class GroupRoleRepositoryAdapter implements GroupRoleRepositoryPort {
 
 	private final GroupRoleRepository groupRoleRepository;
 	private final GroupRolePermissionRepository groupRolePermissionRepository;
-	private final GroupMemberRepository groupMemberRepository;
+	private final GroupMemberRepositoryRepository groupMemberRepository;
 
 	private static final Map<GroupMemberRole, List<GroupPermission>> DEFAULT_PERMS_BY_ROLE =
 		Map.of(
@@ -47,30 +48,33 @@ public class GroupRoleRepositoryAdapter implements GroupRoleRepositoryPort {
 	 * @return
 	 */
 	@Override
-	public Long create(Long groupId) {
-		// 오너 역할 생성
-		Map<GroupMemberRole, Long> roleIdByRole = Arrays.stream(new GroupMemberRole[]{
+	public RoleEntity create(Long groupId) {
+		// 역할 생성
+		Map<GroupMemberRole, RoleEntity> roleEntityByRole =
+			Arrays.stream(new GroupMemberRole[]{
 				GroupMemberRole.OWNER,
 				GroupMemberRole.HEAD_MANAGER,
 				GroupMemberRole.MANAGER,
 				GroupMemberRole.MEMBER
-			})
-			.collect(java.util.stream.Collectors.toMap(
+			}).collect(Collectors.toMap(
 				role -> role,
-				role -> groupRoleRepository.save(RoleEntity.create(groupId, role)).getId()
+				role -> groupRoleRepository.save(RoleEntity.create(groupId, role))
 			));
 
-		// 역할별 기본 권한 세팅 (role-permission 매핑 생성)
+		// 권한 매핑 생성
 		List<PermissionEntity> perms = DEFAULT_PERMS_BY_ROLE.entrySet().stream()
 			.flatMap(e -> e.getValue().stream()
-				.map(p -> PermissionEntity.create(roleIdByRole.get(e.getKey()), p))
+				.map(p -> PermissionEntity.create(
+					roleEntityByRole.get(e.getKey()).getId(),  // roleId 사용
+					p
+				))
 			)
 			.toList();
 
 		groupRolePermissionRepository.saveAll(perms);
 
 		// 그룹 생성자에게 OWNER roleId 리턴 (바깥에서 group_members 생성할 때 사용)
-		return roleIdByRole.get(GroupMemberRole.OWNER);
+		return roleEntityByRole.get(GroupMemberRole.OWNER);
 	}
 
 	/**

src/main/java/flipnote/group/adapter/out/persistence/mapper/GroupMemberMapper.java

@@ -1,16 +1,56 @@
 package flipnote.group.adapter.out.persistence.mapper;
 
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+
 import org.springframework.stereotype.Component;
 
 import flipnote.group.adapter.out.entity.GroupMemberEntity;
+import flipnote.group.adapter.out.entity.RoleEntity;
+import flipnote.group.domain.model.member.GroupMember;
 import flipnote.group.domain.model.member.GroupMemberRole;
+import flipnote.group.domain.model.member.MemberInfo;
 import lombok.AccessLevel;
 import lombok.NoArgsConstructor;
 
 @Component
 @NoArgsConstructor(access = AccessLevel.PRIVATE)
 public class GroupMemberMapper {
-	public static GroupMemberEntity create(Long groupId, Long userId, Long roleId) {
-		return GroupMemberEntity.create(groupId, userId, roleId);
+	public static GroupMemberEntity create(Long groupId, Long userId, RoleEntity role) {
+		return GroupMemberEntity.create(groupId, userId, role);
+	}
+
+	public static GroupMember toDomain(GroupMemberEntity entity) {
+
+		if (entity == null) {
+			return null;
+		}
+
+		return GroupMember.builder()
+			.id(entity.getId())
+			.groupId(entity.getGroupId())
+			.role(entity.getRole())
+			.build();
 	}
+
+	/**
+	 * 그룹 멤버 정보 전체 조회
+	 * @param entities
+	 * @return
+	 */
+	public static List<MemberInfo> toMemberInfo(List<GroupMemberEntity> entities) {
+		if (entities == null || entities.isEmpty()) {
+			return Collections.emptyList();
+		}
+
+		return entities.stream()
+			.map(entity -> MemberInfo.builder()
+				.userId(entity.getUserId())
+				.role(entity.getRole().getRole())
+				.build()
+			)
+			.toList();
+	}
+
 }

src/main/java/flipnote/group/api/dto/response/FindGroupMemberResponseDto.java

@@ -0,0 +1,15 @@
+package flipnote.group.api.dto.response;
+
+import java.util.List;
+
+import flipnote.group.application.port.in.result.FindGroupMemberResult;
+import flipnote.group.domain.model.member.MemberInfo;
+
+public record FindGroupMemberResponseDto(
+	List<MemberInfo> memberInfoList
+) {
+
+	public static FindGroupMemberResponseDto from(FindGroupMemberResult result) {
+		return new FindGroupMemberResponseDto(result.memberInfoList());
+	}
+}

src/main/java/flipnote/group/application/port/in/FindGroupMemberUseCase.java

@@ -0,0 +1,8 @@
+package flipnote.group.application.port.in;
+
+import flipnote.group.application.port.in.command.FindGroupMemberCommand;
+import flipnote.group.application.port.in.result.FindGroupMemberResult;
+
+public interface FindGroupMemberUseCase {
+	FindGroupMemberResult findGroupMember(FindGroupMemberCommand cmd);
+}

src/main/java/flipnote/group/application/port/in/command/FindGroupMemberCommand.java

@@ -0,0 +1,7 @@
+package flipnote.group.application.port.in.command;
+
+public record FindGroupMemberCommand(
+	Long userId,
+	Long groupId
+) {
+}