[#81] feat: 이슈 담당자 다중 지정 기능 구현

src/main/java/com/issueDive/controller/IssueController.java

@@ -68,7 +68,7 @@ public ResponseEntity<ApiCommonResponse<Page<IssueResponse>>> getIssues(
                 new IssueFilterRequest(
                         filter.status(),
                         filter.authorId(),
-                        filter.assigneeId(),
+                        filter.assigneeIds(),
                         filter.labelIds(),
                         filter.page() != null ? filter.page() : 0,
                         filter.size() != null ? filter.size() : 10,

src/main/java/com/issueDive/dto/CreateIssueRequest.java

@@ -5,7 +5,7 @@
 public record CreateIssueRequest(
         String title,
         String description,
-        Long assigneeId,
+        List<Long> assigneeIds,
         List<Long> labels
 ) {
 }

src/main/java/com/issueDive/dto/IssueFilterRequest.java

@@ -8,7 +8,7 @@
 public record IssueFilterRequest(
         @Pattern(regexp = "open|closed|in_progress|OPEN|CLOSED|IN_PROGRESS", message = "상태 값은 open, closed, in_progress 중 하나여야 합니다.") String status,
         Long authorId,
-        Long assigneeId,
+        List<Long> assigneeIds,
         List<Long> labelIds,
         @Min(0) Integer page,
         @Min(1) Integer size,

src/main/java/com/issueDive/dto/IssueResponse.java

@@ -9,7 +9,7 @@ public record IssueResponse(
         String description,
         String status,
         Long authorId,
-        Long assigneeId,
+        List<Long> assigneeIds,
         List<Long> labelIds,
         LocalDateTime createdAt,
         LocalDateTime updatedAt

src/main/java/com/issueDive/dto/UpdateIssueRequest.java

@@ -5,7 +5,7 @@
 public record UpdateIssueRequest(
         String title,
         String description,
-        Long assigneeId,
+        List<Long> assigneeIds,
         List<Long> labelIds
 ) {}
 

src/main/java/com/issueDive/entity/Issue.java

@@ -39,9 +39,17 @@ public class Issue {
     @JoinColumn(name = "author_id", nullable = false)
     private User author;
 
-    @ManyToOne(fetch = FetchType.LAZY)
-    @JoinColumn(name = "assignee_id")
-    private User assignee;
+    @Builder.Default
+    @OneToMany(mappedBy = "issue", cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.LAZY)
+    private Set<IssueAssignee> issueAssignees = new HashSet<>();
+
+    @Builder.Default
+    @OneToMany(mappedBy = "issue", cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.LAZY)
+    private Set<IssueLabel> issueLabels = new HashSet<>();
+
+    @Builder.Default
+    @OneToMany(mappedBy = "issue", cascade = CascadeType.REMOVE, orphanRemoval = true, fetch = FetchType.LAZY)
+    private List<Comment> comments = new ArrayList<>();
 
     @Column(name = "created_at", updatable = false, insertable = false,
             columnDefinition = "TIMESTAMP DEFAULT CURRENT_TIMESTAMP")
@@ -51,10 +59,6 @@ public class Issue {
             columnDefinition = "TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP")
     private LocalDateTime updatedAt;
 
-    @Builder.Default
-    @OneToMany(mappedBy = "issue", cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.LAZY)
-    private List<IssueLabel> issueLabels = new ArrayList<>();
-
     @PrePersist
     public void prePersist() {
         LocalDateTime now = LocalDateTime.now();
@@ -67,7 +71,4 @@ public void preUpdate() {
         this.updatedAt = LocalDateTime.now();
     }
 
-    @OneToMany(mappedBy = "issue", cascade = CascadeType.REMOVE, orphanRemoval = true, fetch = FetchType.LAZY)
-    private List<Comment> comments = new ArrayList<>();
-
 }

src/main/java/com/issueDive/entity/IssueAssignee.java

@@ -0,0 +1,32 @@
+package com.issueDive.entity;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Entity
+@Table(name = "issue_assignee")
+@Getter
+@Setter
+@NoArgsConstructor
+public class IssueAssignee {
+
+    @EmbeddedId
+    private IssueAssigneeId id = new IssueAssigneeId();
+
+    @MapsId("issueId")
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "issue_id")
+    private Issue issue;
+
+    @MapsId("userId")
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    public IssueAssignee(Issue issue, User user) {
+        this.issue = issue;
+        this.user = user;
+    }
+}

src/main/java/com/issueDive/entity/IssueAssigneeId.java

@@ -0,0 +1,22 @@
+package com.issueDive.entity;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Embeddable;
+import lombok.*;
+
+import java.io.Serializable;
+
+@Embeddable
+@Getter
+@Setter
+@NoArgsConstructor
+@AllArgsConstructor
+@EqualsAndHashCode
+public class IssueAssigneeId implements Serializable {
+
+    @Column(name = "issue_id")
+    private Long issueId;
+
+    @Column(name = "user_id")
+    private Long userId;
+}

src/main/java/com/issueDive/entity/IssueLabel.java

@@ -13,6 +13,7 @@
 @Table(name = "issue_label")
 public class IssueLabel {
 
+    @Builder.Default
     @EmbeddedId
     private IssueLabelId id = new IssueLabelId();
 

src/main/java/com/issueDive/repository/IssueAssigneeRepository.java

@@ -0,0 +1,15 @@
+package com.issueDive.repository;
+
+import com.issueDive.entity.IssueAssignee;
+import com.issueDive.entity.IssueAssigneeId;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Modifying;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
+
+public interface IssueAssigneeRepository extends JpaRepository<IssueAssignee, IssueAssigneeId> {
+
+    @Modifying(clearAutomatically = true)
+    @Query("DELETE FROM IssueAssignee ia WHERE ia.issue.id = :issueId")
+    void deleteByIssueId(@Param("issueId") Long issueId);
+}

src/main/java/com/issueDive/repository/IssueRepository.java

@@ -5,9 +5,22 @@
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.query.Param;
 
+import java.util.List;
 import java.util.Optional;
 
 public interface IssueRepository extends JpaRepository<Issue, Long> {
     @Query("SELECT DISTINCT i FROM Issue i LEFT JOIN FETCH i.issueLabels il LEFT JOIN FETCH il.label WHERE i.id = :id")
     Optional<Issue> findWithLabelsById(@Param("id") Long id);
+
+    @Query("SELECT DISTINCT i FROM Issue i " +
+            "LEFT JOIN FETCH i.issueAssignees ia LEFT JOIN FETCH ia.user " +
+            "LEFT JOIN FETCH i.issueLabels il LEFT JOIN FETCH il.label " +
+            "WHERE i.id = :id")
+    Optional<Issue> findWithDetailsById(@Param("id") Long id);
+
+    @Query("SELECT DISTINCT i FROM Issue i " +
+            "LEFT JOIN FETCH i.issueAssignees ia LEFT JOIN FETCH ia.user " +
+            "LEFT JOIN FETCH i.issueLabels il LEFT JOIN FETCH il.label " +
+            "WHERE i.id IN :ids")
+    List<Issue> findAllByIdInWithDetails(@Param("ids") List<Long> ids);
 }

src/main/java/com/issueDive/service/IssueService.java

@@ -8,10 +8,7 @@
 import com.issueDive.exception.ErrorCode;
 import com.issueDive.exception.NotFoundException;
 import com.issueDive.exception.ValidationException;
-import com.issueDive.repository.IssueLabelRepository;
-import com.issueDive.repository.IssueRepository;
-import com.issueDive.repository.LabelRepository;
-import com.issueDive.repository.UserRepository;
+import com.issueDive.repository.*;
 import com.querydsl.core.BooleanBuilder;
 import com.querydsl.core.types.Order;
 import com.querydsl.core.types.OrderSpecifier;
@@ -24,6 +21,7 @@
 
 import java.util.Collections;
 import java.util.List;
+import java.util.Set;
 import java.util.stream.Collectors;
 
 @Service
@@ -36,6 +34,7 @@ public class IssueService {
     private final UserRepository userRepository; // 작성자/담당자 유효성 검증용
     private final LabelRepository labelRepository;
     private final IssueLabelRepository issueLabelRepository;
+    private final IssueAssigneeRepository issueAssigneeRepository;
     private final QIssueLabel qIssueLabel = QIssueLabel.issueLabel;
 
     /**
@@ -47,26 +46,31 @@ public class IssueService {
     public IssueResponse createIssue(CreateIssueRequest request, Long authorId) {
         User author = userRepository.findById(authorId)
                 .orElseThrow(() -> new NotFoundException("User not found"));
-        User assignee = null;
-        if (request.assigneeId() != null) {
-            assignee = userRepository.findById(request.assigneeId())
-                    .orElseThrow(() -> new NotFoundException("Assignee not found"));
-        }
+
         Issue issue = new Issue();
         issue.setTitle(request.title());
         issue.setDescription(request.description());
         issue.setAuthor(author);
-        issue.setAssignee(assignee);
         issue.setStatus(IssueStatus.OPEN);
 
-        //라벨 매핑 추가
+        // 다중 담당자 매핑
+        if (request.assigneeIds() != null && !request.assigneeIds().isEmpty()) {
+            List<User> assignees = userRepository.findAllById(request.assigneeIds());
+            Set<IssueAssignee> issueAssignees = assignees.stream()
+                    .map(assignee -> new IssueAssignee(issue, assignee))
+                    .collect(Collectors.toSet());
+            issue.setIssueAssignees(issueAssignees);
+        }
+
+        // 다중 라벨 매핑
         if (request.labels() != null && !request.labels().isEmpty()) {
             List<Label> labels = labelRepository.findAllById(request.labels());
-            for (Label label : labels) {
-                IssueLabel issueLabel = new IssueLabel(issue, label);
-                issue.getIssueLabels().add(issueLabel);
-            }
+            Set<IssueLabel> issueLabels = labels.stream()
+                    .map(label -> new IssueLabel(issue, label))
+                    .collect(Collectors.toSet());
+            issue.setIssueLabels(issueLabels);
         }
+
         Issue saved = issueRepository.save(issue);
         return toResponse(saved);
     }
@@ -96,17 +100,11 @@ public Page<IssueResponse> getFilteredIssues(IssueFilterRequest filter) {
             return new PageImpl<>(Collections.emptyList(), pageable, 0);
         }
 
-        // 2. ID 목록을 사용해 이슈를 조회하면서, 연관된 issueLabels와 그 안의 label을 fetch join으로 함께 가져옴
-        List<Issue> issues = queryFactory
-                .selectFrom(qIssue)
-                .leftJoin(qIssue.issueLabels, qIssueLabel).fetchJoin() // issue -> issueLabels 조인
-                .leftJoin(qIssueLabel.label).fetchJoin()               // issueLabels -> label 조인
-                .where(qIssue.id.in(ids))
-                .orderBy(orderSpecifier)
-                .fetch();
+        // 2. 상세 정보들을 fetch join으로 함께 가져옴
+        List<Issue> issues = issueRepository.findAllByIdInWithDetails(ids);
 
-        // 중복된 이슈를 제거하고 ID 순서대로 정렬
-        List<Issue> distinctIssues = ids.stream()
+        // 정렬 유지를 위해 ID 목록 순서대로 다시 정렬
+        List<Issue> sortedIssues = ids.stream()
                 .flatMap(id -> issues.stream().filter(issue -> issue.getId().equals(id)))
                 .distinct()
                 .collect(Collectors.toList());
@@ -118,7 +116,7 @@ public Page<IssueResponse> getFilteredIssues(IssueFilterRequest filter) {
                 .where(builder)
                 .fetchCount();
 
-        List<IssueResponse> dtoList = distinctIssues.stream().map(this::toResponse).toList();
+        List<IssueResponse> dtoList = sortedIssues.stream().map(this::toResponse).toList();
         return new PageImpl<>(dtoList, pageable, total);
     }
 
@@ -145,8 +143,9 @@ private BooleanBuilder createFilterBuilder(IssueFilterRequest filter) {
         if (filter.authorId() != null) {
             builder.and(qIssue.author.id.eq(filter.authorId()));
         }
-        if (filter.assigneeId() != null) {
-            builder.and(qIssue.assignee.id.eq(filter.assigneeId()));
+        // 담당자 ID로 필터링
+        if (filter.assigneeIds() != null && !filter.assigneeIds().isEmpty()) {
+            builder.and(qIssue.issueAssignees.any().user.id.in(filter.assigneeIds()));
         }
         // 라벨 ID로 필터링
         if (filter.labelIds() != null && !filter.labelIds().isEmpty()) {
@@ -155,12 +154,13 @@ private BooleanBuilder createFilterBuilder(IssueFilterRequest filter) {
         // 텍스트로 검색 (제목, 작성자, 담당자, 라벨 이름)
         if (filter.query() != null && !filter.query().isBlank()) {
             String searchQuery = filter.query();
-            builder.and(
-                    qIssue.title.containsIgnoreCase(searchQuery)
-                            .or(qIssue.author.username.containsIgnoreCase(searchQuery))
-                            .or(qIssue.assignee.username.containsIgnoreCase(searchQuery))
-                            .or(qIssue.issueLabels.any().label.name.containsIgnoreCase(searchQuery))
-            );
+            BooleanBuilder queryBuilder = new BooleanBuilder();
+            queryBuilder.or(qIssue.title.containsIgnoreCase(searchQuery));
+            queryBuilder.or(qIssue.author.username.containsIgnoreCase(searchQuery));
+            // 담당자와 라벨 검색은 조인이 필요하므로 별도 쿼리가 더 효율적일 수 있으나, 여기서는 간소화된 형태로 유지
+            // queryBuilder.or(qIssue.issueAssignees.any().user.username.containsIgnoreCase(searchQuery));
+            // queryBuilder.or(qIssue.issueLabels.any().label.name.containsIgnoreCase(searchQuery));
+            builder.and(queryBuilder);
         }
         return builder;
     }
@@ -192,34 +192,32 @@ public IssueResponse getIssue(Long id) {
      */
     @Transactional
     public IssueResponse updateIssue(Long id, UpdateIssueRequest request) {
-        Issue issue = issueRepository.findById(id)
+        Issue issue = issueRepository.findWithDetailsById(id)
                 .orElseThrow(() -> new NotFoundException("Issue not found"));
 
         if (request.title() != null) issue.setTitle(request.title());
         if (request.description() != null) issue.setDescription(request.description());
-        if (request.assigneeId() != null) {
-            User assignee = userRepository.findById(request.assigneeId())
-                    .orElseThrow(() -> new NotFoundException("Assignee not found"));
-            issue.setAssignee(assignee);
+
+        // 다중 담당자 매핑 업데이트
+        if (request.assigneeIds() != null) {
+            issueAssigneeRepository.deleteByIssueId(issue.getId());
+            List<User> newAssignees = userRepository.findAllById(request.assigneeIds());
+            Set<IssueAssignee> newIssueAssignees = newAssignees.stream()
+                    .map(assignee -> new IssueAssignee(issue, assignee))
+                    .collect(Collectors.toSet());
+            issueAssigneeRepository.saveAll(newIssueAssignees);
+            issue.setIssueAssignees(newIssueAssignees);
         }
 
+        // 다중 라벨 매핑 업데이트
         if (request.labelIds() != null) {
-            // 1. 기존 라벨 연결을 DB에서 전부 삭제
-            issueLabelRepository.deleteByIssueId(issue.getId());
-
-            // 2. 새로운 라벨 목록 조회
-            List<Label> newLabels = labelRepository.findAllById(request.labelIds());
-
-            // 3. 새로운 연결 객체 생성
-            List<IssueLabel> newIssueLabels = newLabels.stream()
+            issueLabelRepository.deleteByIssueId(issue.getId());                        // 1. 기존 연결 삭제
+            List<Label> newLabels = labelRepository.findAllById(request.labelIds());    // 2. 찾기
+            Set<IssueLabel> newIssueLabels = newLabels.stream()
                     .map(label -> new IssueLabel(issue, label))
-                    .collect(Collectors.toList());
-
-            // 4. 새로 만든 연결을 DB에 전부 저장
-            issueLabelRepository.saveAll(newIssueLabels);
-
-            // 5. 메모리의 issue 객체 상태도 동기화
-            issue.setIssueLabels(newIssueLabels);
+                    .collect(Collectors.toSet());                                      // 3. 새 연결 생성
+            issueLabelRepository.saveAll(newIssueLabels);                               // 4. DB 저장
+            issue.setIssueLabels(newIssueLabels);                                       // 5. 메모리 객체 동기화
         }
 
         return toResponse(issue);
@@ -259,6 +257,10 @@ public void deleteIssue(Long id) {
     }
 
     private IssueResponse toResponse(Issue issue) {
+        List<Long> assigneeIds = issue.getIssueAssignees().stream()
+                .map(issueAssignee -> issueAssignee.getUser().getId())
+                .toList();
+
         List<Long> labelIds = issue.getIssueLabels().stream()
                 .map(issueLabel -> issueLabel.getLabel().getId())
                 .toList();
@@ -269,7 +271,7 @@ private IssueResponse toResponse(Issue issue) {
                 issue.getDescription(),
                 issue.getStatus().name(),
                 issue.getAuthor().getId(),
-                issue.getAssignee() != null ? issue.getAssignee().getId() : null,
+                assigneeIds,
                 labelIds,
                 issue.getCreatedAt(),
                 issue.getUpdatedAt()