[feat]: 공지사항 작성 API 구현

src/main/java/com/mulmi/backend/domain/notice/controller/NoticeController.java

@@ -1,18 +1,24 @@
 package com.mulmi.backend.domain.notice.controller;
 
+import com.mulmi.backend.domain.notice.dto.request.NoticeCreateRequestDTO;
 import com.mulmi.backend.domain.notice.dto.response.NoticeDetailResponseDTO;
 import com.mulmi.backend.domain.notice.dto.response.NoticePageResponseDTO;
 import com.mulmi.backend.domain.notice.exception.code.NoticeSuccessCode;
 import com.mulmi.backend.domain.notice.service.NoticeService;
 import com.mulmi.backend.global.apiPayload.ApiResponse;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
+import jakarta.validation.Valid;
 import jakarta.validation.constraints.Max;
 import jakarta.validation.constraints.Min;
 import lombok.RequiredArgsConstructor;
 import org.springframework.validation.annotation.Validated;
+import org.springframework.security.access.prepost.PreAuthorize;
+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.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
@@ -51,4 +57,18 @@ public ApiResponse<NoticeDetailResponseDTO> getNotice(
                 noticeService.getNotice(noticeId)
         );
     }
+
+    // 공지사항 작성
+    @Operation(summary = "공지사항 작성")
+    @PostMapping
+    @PreAuthorize("hasAnyRole('ASSISTANT', 'WORKER')")
+    public ApiResponse<NoticeDetailResponseDTO> createNotice(
+            @AuthenticationPrincipal Long userId,
+            @RequestBody @Valid NoticeCreateRequestDTO dto
+    ) {
+        return ApiResponse.onSuccess(
+                NoticeSuccessCode.NOTICE_CREATED,
+                noticeService.createNotice(userId, dto)
+        );
+    }
 }

src/main/java/com/mulmi/backend/domain/notice/converter/NoticeConverter.java

@@ -1,14 +1,25 @@
 package com.mulmi.backend.domain.notice.converter;
 
+import com.mulmi.backend.domain.notice.dto.request.NoticeCreateRequestDTO;
 import com.mulmi.backend.domain.notice.dto.response.NoticeDetailResponseDTO;
 import com.mulmi.backend.domain.notice.dto.response.NoticeSummaryResponseDTO;
 import com.mulmi.backend.domain.notice.entity.Notice;
+import com.mulmi.backend.domain.user.entity.User;
 
 public class NoticeConverter {
 
     private NoticeConverter() {
     }
 
+    public static Notice toNotice(NoticeCreateRequestDTO dto, User author) {
+        return Notice.builder()
+                .title(dto.title().trim())
+                .content(dto.content().trim())
+                .important(dto.important())
+                .author(author)
+                .build();
+    }
+
     public static NoticeSummaryResponseDTO toNoticeSummaryResponseDTO(Notice notice) {
         return new NoticeSummaryResponseDTO(
                 notice.getId(),

src/main/java/com/mulmi/backend/domain/notice/dto/request/NoticeCreateRequestDTO.java

@@ -0,0 +1,16 @@
+package com.mulmi.backend.domain.notice.dto.request;
+
+import jakarta.validation.constraints.NotBlank;
+import jakarta.validation.constraints.Size;
+
+public record NoticeCreateRequestDTO(
+        @NotBlank(message = "공지사항 제목은 필수입니다.")
+        @Size(max = 200, message = "공지사항 제목은 200자를 넘을 수 없습니다.")
+        String title,
+
+        @NotBlank(message = "공지사항 내용은 필수입니다.")
+        String content,
+
+        boolean important
+) {
+}

src/main/java/com/mulmi/backend/domain/notice/exception/code/NoticeSuccessCode.java

@@ -17,6 +17,11 @@ public enum NoticeSuccessCode implements BaseSuccessCode {
             HttpStatus.OK,
             "NOTICE200_2",
             "공지사항을 조회했습니다."
+    ),
+    NOTICE_CREATED(
+            HttpStatus.CREATED,
+            "NOTICE201_1",
+            "공지사항을 작성했습니다."
     );
 
     private final HttpStatus status;

src/main/java/com/mulmi/backend/domain/notice/service/NoticeService.java

@@ -1,5 +1,6 @@
 package com.mulmi.backend.domain.notice.service;
 
+import com.mulmi.backend.domain.notice.dto.request.NoticeCreateRequestDTO;
 import com.mulmi.backend.domain.notice.dto.response.NoticeDetailResponseDTO;
 import com.mulmi.backend.domain.notice.dto.response.NoticePageResponseDTO;
 
@@ -8,4 +9,6 @@ public interface NoticeService {
     NoticePageResponseDTO getNotices(Boolean important, int page, int size);
 
     NoticeDetailResponseDTO getNotice(Long noticeId);
+
+    NoticeDetailResponseDTO createNotice(Long authorId, NoticeCreateRequestDTO dto);
 }

src/main/java/com/mulmi/backend/domain/notice/service/NoticeServiceImpl.java

@@ -1,13 +1,19 @@
 package com.mulmi.backend.domain.notice.service;
 
 import com.mulmi.backend.domain.notice.converter.NoticeConverter;
+import com.mulmi.backend.domain.notice.dto.request.NoticeCreateRequestDTO;
 import com.mulmi.backend.domain.notice.dto.response.NoticeDetailResponseDTO;
 import com.mulmi.backend.domain.notice.dto.response.NoticePageResponseDTO;
 import com.mulmi.backend.domain.notice.dto.response.NoticeSummaryResponseDTO;
 import com.mulmi.backend.domain.notice.entity.Notice;
 import com.mulmi.backend.domain.notice.exception.NoticeException;
 import com.mulmi.backend.domain.notice.exception.code.NoticeErrorCode;
 import com.mulmi.backend.domain.notice.repository.NoticeRepository;
+import com.mulmi.backend.domain.user.entity.User;
+import com.mulmi.backend.domain.user.enums.UserStatus;
+import com.mulmi.backend.domain.user.exception.UserException;
+import com.mulmi.backend.domain.user.exception.code.UserErrorCode;
+import com.mulmi.backend.domain.user.repository.UserRepository;
 import lombok.RequiredArgsConstructor;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.PageRequest;
@@ -21,6 +27,7 @@
 public class NoticeServiceImpl implements NoticeService {
 
     private final NoticeRepository noticeRepository;
+    private final UserRepository userRepository;
 
     @Override
     public NoticePageResponseDTO getNotices(Boolean important, int page, int size) {
@@ -45,4 +52,23 @@ public NoticeDetailResponseDTO getNotice(Long noticeId) {
 
         return NoticeConverter.toNoticeDetailResponseDTO(notice);
     }
+
+    @Override
+    @Transactional
+    public NoticeDetailResponseDTO createNotice(
+            Long authorId,
+            NoticeCreateRequestDTO dto
+    ) {
+        User author = userRepository.findById(authorId)
+                .orElseThrow(() -> new UserException(UserErrorCode.USER_NOT_FOUND));
+
+        if (author.getStatus() != UserStatus.ACTIVE) {
+            throw new UserException(UserErrorCode.INACTIVE_USER);
+        }
+
+        Notice notice = NoticeConverter.toNotice(dto, author);
+        Notice savedNotice = noticeRepository.save(notice);
+
+        return NoticeConverter.toNoticeDetailResponseDTO(savedNotice);
+    }
 }

src/test/java/com/mulmi/backend/domain/notice/service/NoticeServiceImplTest.java

@@ -1,5 +1,6 @@
 package com.mulmi.backend.domain.notice.service;
 
+import com.mulmi.backend.domain.notice.dto.request.NoticeCreateRequestDTO;
 import com.mulmi.backend.domain.notice.dto.response.NoticeDetailResponseDTO;
 import com.mulmi.backend.domain.notice.dto.response.NoticePageResponseDTO;
 import com.mulmi.backend.domain.notice.entity.Notice;
@@ -9,6 +10,9 @@
 import com.mulmi.backend.domain.user.entity.User;
 import com.mulmi.backend.domain.user.enums.UserRole;
 import com.mulmi.backend.domain.user.enums.UserStatus;
+import com.mulmi.backend.domain.user.exception.UserException;
+import com.mulmi.backend.domain.user.exception.code.UserErrorCode;
+import com.mulmi.backend.domain.user.repository.UserRepository;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
@@ -24,6 +28,7 @@
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.mockito.BDDMockito.given;
+import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.verify;
 
 @ExtendWith(MockitoExtension.class)
@@ -32,6 +37,9 @@ class NoticeServiceImplTest {
     @Mock
     private NoticeRepository noticeRepository;
 
+    @Mock
+    private UserRepository userRepository;
+
     @InjectMocks
     private NoticeServiceImpl noticeService;
 
@@ -118,6 +126,52 @@ void getNoticeThrowsWhenNoticeDoesNotExist() {
                 .isEqualTo(NoticeErrorCode.NOTICE_NOT_FOUND);
     }
 
+    @Test
+    void createNoticeSavesNoticeWithAuthenticatedAuthor() {
+        User author = createAuthor();
+        NoticeCreateRequestDTO request = new NoticeCreateRequestDTO(
+                " 대여실 운영 안내 ",
+                " 운영 시간을 안내합니다. ",
+                true
+        );
+        given(userRepository.findById(2L)).willReturn(Optional.of(author));
+        given(noticeRepository.save(any(Notice.class)))
+                .willAnswer(invocation -> invocation.getArgument(0));
+
+        NoticeDetailResponseDTO result = noticeService.createNotice(2L, request);
+
+        assertThat(result.title()).isEqualTo("대여실 운영 안내");
+        assertThat(result.content()).isEqualTo("운영 시간을 안내합니다.");
+        assertThat(result.important()).isTrue();
+        assertThat(result.authorId()).isEqualTo(2L);
+        verify(noticeRepository).save(any(Notice.class));
+    }
+
+    @Test
+    void createNoticeThrowsWhenAuthorIsInactive() {
+        User inactiveAuthor = User.builder()
+                .id(2L)
+                .loginId("assistant")
+                .password("encoded-password")
+                .name("조교")
+                .email("assistant@example.com")
+                .phoneNumber("01012345678")
+                .role(UserRole.ASSISTANT)
+                .status(UserStatus.SUSPENDED)
+                .build();
+        NoticeCreateRequestDTO request = new NoticeCreateRequestDTO(
+                "공지사항",
+                "공지사항 내용",
+                false
+        );
+        given(userRepository.findById(2L)).willReturn(Optional.of(inactiveAuthor));
+
+        assertThatThrownBy(() -> noticeService.createNotice(2L, request))
+                .isInstanceOf(UserException.class)
+                .extracting("code")
+                .isEqualTo(UserErrorCode.INACTIVE_USER);
+    }
+
     private User createAuthor() {
         return User.builder()
                 .id(2L)