[FEAT] 키워드 검색 API 추가

src/main/java/ku_rum/backend/domain/notice/application/NoticeService.java

@@ -9,6 +9,7 @@
 import ku_rum.backend.domain.notice.domain.repository.NoticeRepository;
 import ku_rum.backend.domain.notice.dto.response.NoticeDetailResponse;
 import ku_rum.backend.domain.notice.dto.response.NoticeResponse;
+import ku_rum.backend.domain.search.application.RecentSearchService;
 import ku_rum.backend.domain.user.application.UserService;
 import ku_rum.backend.domain.user.domain.User;
 import ku_rum.backend.global.exception.global.GlobalException;
@@ -36,6 +37,7 @@ public class NoticeService {
     private final NoticeDetailRepository noticeDetailRepository;
     private final BookmarkRepository bookmarkRepository;
     private final UserService userService;
+    private final RecentSearchService recentSearchService;
 
     public Page<NoticeResponse> findByCategory(Long categoryId, Pageable pageable) {
         return noticeRepository.findByCategoryIdAndPublishStatus(categoryId, PublishStatus.SUCCESS_CRAWLING, pageable)
@@ -84,6 +86,8 @@ public List<NoticeResponse> findPrimaryNotices() {
 
     // 키워드 검색 로직
     public Page<NoticeResponse> searchByKeyword(String keyword, Pageable pageable) {
+        recentSearchService.save(keyword);
+
         return noticeRepository.searchByKeyword(keyword, PublishStatus.SUCCESS_CRAWLING, pageable)
                 .map(NoticeResponse::from);
     }

src/main/java/ku_rum/backend/domain/notice/presentation/NoticeController.java

@@ -53,4 +53,5 @@ public Page<NoticeResponse> searchNoticesByKeyword(
     ) {
         return noticeService.searchByKeyword(keyword, pageable);
     }
+
 }

src/main/java/ku_rum/backend/domain/search/application/RecentSearchService.java

@@ -0,0 +1,93 @@
+package ku_rum.backend.domain.search.application;
+
+import ku_rum.backend.domain.search.domain.RecentSearch;
+import ku_rum.backend.domain.search.domain.repository.RecentSearchRepository;
+import ku_rum.backend.domain.user.application.UserService;
+import ku_rum.backend.domain.user.domain.User;
+import lombok.RequiredArgsConstructor;
+import org.springframework.dao.DataIntegrityViolationException;
+import org.springframework.data.domain.PageRequest;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor
+public class RecentSearchService {
+
+    private static final int MAX_RECENT_SEARCH = 20;
+
+    private final RecentSearchRepository repository;
+    private final UserService userService;
+
+    @Transactional
+    public void save(String keyword) {
+        String normalized = normalizeKeyword(keyword);
+        if (normalized == null) {
+            return;
+        }
+
+        User user = userService.getUser();
+        LocalDateTime now = LocalDateTime.now();
+
+        try {
+            repository.findByUserIdAndKeyword(user.getId(), normalized)
+                    .ifPresentOrElse(
+                            rs -> rs.touch(now),
+                            () -> repository.save(
+                                    new RecentSearch(user.getId(), normalized, now)
+                            )
+                    );
+        } catch (DataIntegrityViolationException e) {
+            repository.findByUserIdAndKeyword(user.getId(), normalized)
+                    .ifPresent(rs -> rs.touch(now));
+        }
+
+        deleteRecentKeywordsOversize(user);
+    }
+
+    private void deleteRecentKeywordsOversize(User user) {
+        List<RecentSearch> list =
+                repository.findByUserIdOrderByUpdatedAtDesc(
+                        user.getId(),
+                        PageRequest.of(0, MAX_RECENT_SEARCH + 1)
+                );
+
+        if (list.size() > MAX_RECENT_SEARCH) {
+            repository.deleteAll(list.subList(MAX_RECENT_SEARCH, list.size()));
+        }
+    }
+
+    private String normalizeKeyword(String keyword) {
+        if (keyword == null) {
+            return null;
+        }
+
+        String trimmed = keyword.trim();
+        if (trimmed.isEmpty()) return null;
+        return trimmed;
+    }
+
+    @Transactional(readOnly = true)
+    public List<RecentSearch> list(final int limit) {
+        User user = userService.getUser();
+        return repository.findByUserIdOrderByUpdatedAtDesc(
+                user.getId(),
+                PageRequest.of(0, limit)
+        );
+    }
+
+    @Transactional
+    public void delete(Long id) {
+        User user = userService.getUser();
+        repository.deleteByIdAndUserId(id, user.getId());
+    }
+
+    @Transactional
+    public void deleteAll() {
+        User user = userService.getUser();
+        repository.deleteByUserId(user.getId());
+    }
+}

src/main/java/ku_rum/backend/domain/search/domain/RecentSearch.java

@@ -0,0 +1,51 @@
+package ku_rum.backend.domain.search.domain;
+
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+import java.time.LocalDateTime;
+
+@Getter
+@NoArgsConstructor
+@Entity
+@Table(
+        name = "recent_search",
+        uniqueConstraints = @UniqueConstraint(
+                name = "uk_recent_search_user_keyword",
+                columnNames = {"user_id", "keyword"}
+        ),
+        indexes = @Index(
+                name = "idx_recent_search_user_updated",
+                columnList = "user_id, updated_at"
+        )
+)
+public class RecentSearch {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(name = "user_id", nullable = false)
+    private Long userId;
+
+    @Column(nullable = false, length = 255)
+    private String keyword;
+
+    @Column(name = "created_at", nullable = false)
+    private LocalDateTime createdAt;
+
+    @Column(name = "updated_at", nullable = false)
+    private LocalDateTime updatedAt;
+
+    public RecentSearch(Long userId, String keyword, LocalDateTime now) {
+        this.userId = userId;
+        this.keyword = keyword;
+        this.createdAt = now;
+        this.updatedAt = now;
+    }
+
+    public void touch(LocalDateTime now) {
+        this.updatedAt = now;
+    }
+}

src/main/java/ku_rum/backend/domain/search/domain/repository/RecentSearchRepository.java

@@ -0,0 +1,19 @@
+package ku_rum.backend.domain.search.domain.repository;
+
+import ku_rum.backend.domain.search.domain.RecentSearch;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import java.util.List;
+import java.util.Optional;
+
+public interface RecentSearchRepository extends JpaRepository<RecentSearch, Long> {
+
+    Optional<RecentSearch> findByUserIdAndKeyword(Long userId, String keyword);
+
+    List<RecentSearch> findByUserIdOrderByUpdatedAtDesc(Long userId, Pageable pageable);
+
+    long deleteByIdAndUserId(Long id, Long userId);
+
+    long deleteByUserId(Long userId);
+}

src/main/java/ku_rum/backend/domain/search/presentation/RecentSearchController.java

@@ -0,0 +1,35 @@
+package ku_rum.backend.domain.search.presentation;
+
+import ku_rum.backend.domain.search.application.RecentSearchService;
+import ku_rum.backend.domain.search.domain.RecentSearch;
+import ku_rum.backend.global.support.response.BaseResponse;
+import lombok.RequiredArgsConstructor;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+
+@RestController
+@RequestMapping("/api/v1/notices/searches/recent")
+@RequiredArgsConstructor
+public class RecentSearchController {
+
+    private final RecentSearchService recentSearchService;
+
+    @GetMapping
+    public BaseResponse<List<RecentSearch>> list(
+            @RequestParam(defaultValue = "20") int limit) {
+        return BaseResponse.ok(recentSearchService.list(limit));
+    }
+
+    @DeleteMapping("/{id}")
+    public BaseResponse<Void> delete(@PathVariable Long id) {
+        recentSearchService.delete(id);
+        return BaseResponse.ok(null);
+    }
+
+    @DeleteMapping("/all")
+    public BaseResponse<Void> deleteAll() {
+        recentSearchService.deleteAll();
+        return BaseResponse.ok(null);
+    }
+}

src/test/java/ku_rum/backend/domain/search/presentation/RecentSearchControllerTest.java

@@ -0,0 +1,150 @@
+package ku_rum.backend.domain.search.presentation;
+
+import com.epages.restdocs.apispec.ResourceSnippetParameters;
+import ku_rum.backend.config.RestDocsTestSupport;
+import ku_rum.backend.domain.search.application.RecentSearchService;
+import ku_rum.backend.domain.search.domain.RecentSearch;
+import ku_rum.backend.global.domain.repository.ApiLogRepository;
+import ku_rum.backend.global.security.JwtTokenAuthenticationFilter;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.http.MediaType;
+import org.springframework.restdocs.payload.JsonFieldType;
+import org.springframework.security.test.context.support.WithMockUser;
+import org.springframework.security.web.SecurityFilterChain;
+import org.springframework.test.context.ActiveProfiles;
+import org.springframework.test.util.ReflectionTestUtils;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+import static com.epages.restdocs.apispec.ResourceDocumentation.resource;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.Mockito.doNothing;
+import static org.springframework.restdocs.mockmvc.RestDocumentationRequestBuilders.delete;
+import static org.springframework.restdocs.mockmvc.RestDocumentationRequestBuilders.get;
+import static org.springframework.restdocs.payload.PayloadDocumentation.fieldWithPath;
+import static org.springframework.restdocs.request.RequestDocumentation.parameterWithName;
+import static org.springframework.test.web.servlet.result.MockMvcResultHandlers.print;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+@WebMvcTest(RecentSearchController.class)
+@ActiveProfiles("test")
+class RecentSearchControllerTest extends RestDocsTestSupport {
+
+    @MockBean
+    private RecentSearchService recentSearchService;
+
+    @MockBean
+    private ApiLogRepository apiLogRepository;
+
+    @MockBean
+    private SecurityFilterChain securityFilterChain;
+
+    @MockBean
+    private JwtTokenAuthenticationFilter jwtTokenAuthenticationFilter;
+
+
+    @Test
+    @DisplayName("최근 검색어 목록을 조회한다")
+    @WithMockUser
+    void getRecentSearches() throws Exception {
+        // given
+        List<RecentSearch> response = List.of(
+                mockRecentSearch(1L, 1L, "장학금"),
+                mockRecentSearch(2L, 1L, "등록금")
+        );
+
+        given(recentSearchService.list(20)).willReturn(response);
+
+        // when & then
+        mockMvc.perform(get("/api/v1/recent-searches")
+                        .param("limit", "20")
+                        .contentType(MediaType.APPLICATION_JSON)
+                )
+                .andDo(print())
+                .andExpect(status().isOk())
+                .andDo(restDocs.document(
+                        resource(
+                                ResourceSnippetParameters.builder()
+                                        .tag("최근 검색어 API")
+                                        .description("최근 검색어 목록 조회")
+                                        .queryParameters(
+                                                parameterWithName("limit")
+                                                        .description("조회할 최근 검색어 개수 (기본값 20)")
+                                        )
+                                        .responseFields(
+                                                fieldWithPath("code").type(JsonFieldType.NUMBER).description("응답 코드"),
+                                                fieldWithPath("status").type(JsonFieldType.STRING).description("응답 상태"),
+                                                fieldWithPath("message").type(JsonFieldType.STRING).description("응답 메시지"),
+                                                fieldWithPath("data[].id").type(JsonFieldType.NUMBER).description("최근 검색어 ID"),
+                                                fieldWithPath("data[].userId").type(JsonFieldType.NUMBER).description("유저 ID"),
+                                                fieldWithPath("data[].keyword").type(JsonFieldType.STRING).description("검색 키워드"),
+                                                fieldWithPath("data[].createdAt").type(JsonFieldType.STRING).description("생성 시각"),
+                                                fieldWithPath("data[].updatedAt").type(JsonFieldType.STRING).description("최근 검색 시각")
+                                        )
+                                        .build()
+                        )
+                ));
+    }
+
+    @Test
+    @DisplayName("최근 검색어를 단건 삭제한다")
+    @WithMockUser
+    void deleteRecentSearch() throws Exception {
+        doNothing().when(recentSearchService).delete(1L);
+
+        mockMvc.perform(delete("/api/v1/recent-searches/{id}", 1L)
+                        .contentType(MediaType.APPLICATION_JSON)
+                )
+                .andDo(print())
+                .andExpect(status().isOk())
+                .andDo(restDocs.document(
+                        resource(
+                                ResourceSnippetParameters.builder()
+                                        .tag("최근 검색어 API")
+                                        .description("최근 검색어 단건 삭제")
+                                        .responseFields(
+                                                fieldWithPath("code").type(JsonFieldType.NUMBER).description("응답 코드"),
+                                                fieldWithPath("status").type(JsonFieldType.STRING).description("응답 상태"),
+                                                fieldWithPath("message").type(JsonFieldType.STRING).description("응답 메시지")
+                                        )
+                                        .build()
+                        )
+                ));
+    }
+
+    @Test
+    @DisplayName("최근 검색어 전체 삭제")
+    @WithMockUser
+    void deleteAllRecentSearches() throws Exception {
+        doNothing().when(recentSearchService).deleteAll();
+
+        mockMvc.perform(delete("/api/v1/recent-searches/all")
+                        .contentType(MediaType.APPLICATION_JSON)
+                )
+                .andDo(print())
+                .andExpect(status().isOk())
+                .andDo(restDocs.document(
+                        resource(
+                                ResourceSnippetParameters.builder()
+                                        .tag("최근 검색어 API")
+                                        .description("최근 검색어 전체 삭제")
+                                        .responseFields(
+                                                fieldWithPath("code").type(JsonFieldType.NUMBER).description("응답 코드"),
+                                                fieldWithPath("status").type(JsonFieldType.STRING).description("응답 상태"),
+                                                fieldWithPath("message").type(JsonFieldType.STRING).description("응답 메시지")
+                                        )
+                                        .build()
+                        )
+                ));
+    }
+
+    private RecentSearch mockRecentSearch(Long id, Long userId, String keyword) {
+        RecentSearch rs = new RecentSearch(userId, keyword, LocalDateTime.now());
+        ReflectionTestUtils.setField(rs, "id", id);
+        return rs;
+    }
+}