feat: 내 템플릿 상세 조회 API (#49)

src/main/java/com/sniptext/domain/template/controller/TemplateController.java

@@ -1,15 +1,21 @@
 package com.sniptext.domain.template.controller;
 
 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.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
 import com.sniptext.domain.template.controller.dto.TemplateCreateRequest;
 import com.sniptext.domain.template.controller.dto.TemplateCreateResponse;
+import com.sniptext.domain.template.controller.dto.TemplateDetailResponse;
 import com.sniptext.domain.template.service.TemplateCommandService;
+import com.sniptext.domain.template.service.TemplateQueryService;
+import com.sniptext.domain.template.service.dto.query.TemplateDetailQuery;
 import com.sniptext.domain.template.service.dto.result.TemplateCreateResult;
+import com.sniptext.domain.template.service.dto.result.TemplateDetailResult;
 import com.sniptext.global.response.ApiResponse;
 import com.sniptext.global.security.LoginUser;
 
@@ -25,6 +31,17 @@
 public class TemplateController {
 
 	private final TemplateCommandService templateCommandService;
+	private final TemplateQueryService templateQueryService;
+
+	@GetMapping("/{templateId}")
+	public ResponseEntity<ApiResponse<TemplateDetailResponse>> getTemplate(
+		@LoginUser Long userId,
+		@PathVariable Long templateId) {
+
+		TemplateDetailResult result = templateQueryService.getTemplate(new TemplateDetailQuery(userId, templateId));
+
+		return ApiResponse.success(TemplateSuccessCode.TEMPLATE_FOUND, TemplateDetailResponse.from(result));
+	}
 
 	@PostMapping
 	public ResponseEntity<ApiResponse<TemplateCreateResponse>> createTemplate(

src/main/java/com/sniptext/domain/template/controller/TemplateSuccessCode.java

@@ -11,6 +11,7 @@
 @RequiredArgsConstructor
 public enum TemplateSuccessCode implements ResultCode {
 
+	TEMPLATE_FOUND(HttpStatus.OK, "TEMPLATE200_2", "템플릿 조회에 성공했습니다."),
 	TEMPLATE_CREATED(HttpStatus.CREATED, "TEMPLATE201_1", "템플릿이 저장되었습니다.");
 
 	private final HttpStatus httpStatus;

src/main/java/com/sniptext/domain/template/controller/dto/TemplateDetailResponse.java

@@ -0,0 +1,33 @@
+package com.sniptext.domain.template.controller.dto;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+import com.sniptext.domain.template.service.dto.result.TemplateDetailResult;
+
+/** 내 템플릿 상세 (명세 9번). 시각은 전역 직렬화 설정이 +09:00을 붙여 내보낸다. */
+public record TemplateDetailResponse(
+	Long templateId,
+	String title,
+	String shortcut,
+	String content,
+	List<String> variables,
+	LocalDateTime lastUsedAt,
+	LocalDateTime createdAt,
+	LocalDateTime editedAt
+) {
+
+	public static TemplateDetailResponse from(TemplateDetailResult result) {
+		return new TemplateDetailResponse(
+			result.templateId(),
+			result.title(),
+			result.shortcut(),
+			result.content(),
+			result.variables(),
+			result.lastUsedAt(),
+			result.createdAt(),
+			result.editedAt()
+		);
+	}
+
+}

src/main/java/com/sniptext/domain/template/exception/TemplateErrorCode.java

@@ -30,6 +30,10 @@ public enum TemplateErrorCode implements ResultCode {
 	CONTENT_TOO_LONG(HttpStatus.BAD_REQUEST, "TEMPLATE400_7", "템플릿 내용은 3,000자까지 입력할 수 있어요."),
 	/** 활성 템플릿 수가 플랜 한도 이상 (화면은 한도 모달) */
 	TEMPLATE_LIMIT_REACHED(HttpStatus.FORBIDDEN, "TEMPLATE403_1", "템플릿 저장 한도에 도달했어요."),
+	/** 없는 템플릿, 다른 회원의 템플릿 (다른 회원의 휴지통 템플릿 포함) */
+	TEMPLATE_NOT_FOUND(HttpStatus.NOT_FOUND, "TEMPLATE404_1", "템플릿을 찾을 수 없어요."),
+	/** 내 템플릿인데 휴지통에 있음 */
+	TEMPLATE_IN_TRASH(HttpStatus.NOT_FOUND, "TEMPLATE404_2", "이미 삭제된 템플릿이에요."),
 	/** 내 템플릿(휴지통 제외)에 같은 단축어 키가 있음. 대소문자 무시 */
 	SHORTCUT_DUPLICATED(HttpStatus.CONFLICT, "TEMPLATE409_1", "이미 사용 중인 단축어예요."),
 	/** 자동 번호 2~99가 모두 사용 중 (갤러리 저장·휴지통 복구) */

src/main/java/com/sniptext/domain/template/repository/TemplateRepository.java

@@ -3,6 +3,7 @@
 import java.time.LocalDateTime;
 import java.util.Collection;
 import java.util.List;
+import java.util.Optional;
 import java.util.Set;
 
 import org.springframework.data.domain.Limit;
@@ -15,6 +16,9 @@
 
 public interface TemplateRepository extends JpaRepository<Template, Long> {
 
+	/** 본인 소유 조회. 휴지통 템플릿도 찾으므로 내 휴지통과 다른 회원 것을 호출자가 구분할 수 있다 */
+	Optional<Template> findByIdAndUserId(Long id, Long userId);
+
 	/** 휴지통을 제외한 보유 개수. idx_templates_user_deleted (user_id, deleted_at)를 탄다 */
 	long countByUserIdAndDeletedAtIsNull(Long userId);
 

src/main/java/com/sniptext/domain/template/service/TemplateQueryService.java

@@ -3,7 +3,12 @@
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
+import com.sniptext.domain.template.entity.Template;
+import com.sniptext.domain.template.exception.TemplateErrorCode;
 import com.sniptext.domain.template.repository.TemplateRepository;
+import com.sniptext.domain.template.service.dto.query.TemplateDetailQuery;
+import com.sniptext.domain.template.service.dto.result.TemplateDetailResult;
+import com.sniptext.global.exception.BusinessException;
 
 import lombok.RequiredArgsConstructor;
 
@@ -19,4 +24,22 @@ public long countActive(Long userId) {
 		return templateRepository.countByUserIdAndDeletedAtIsNull(userId);
 	}
 
+	/** 내 템플릿 상세. 없거나 다른 회원 것이면 TEMPLATE404_1, 휴지통에 있으면 TEMPLATE404_2 */
+	public TemplateDetailResult getTemplate(TemplateDetailQuery query) {
+		return TemplateDetailResult.from(getActiveTemplate(query.userId(), query.templateId()));
+	}
+
+	/**
+	 * 휴지통에 없는 본인 템플릿. 수정·사용 기록도 같은 404 구분을 쓴다.
+	 * 엔티티를 돌려주므로 template 도메인 안에서만 부른다 (패키지 범위라 service 패키지 밖에서는 부를 수 없다).
+	 */
+	Template getActiveTemplate(Long userId, Long templateId) {
+		Template template = templateRepository.findByIdAndUserId(templateId, userId)
+			.orElseThrow(() -> new BusinessException(TemplateErrorCode.TEMPLATE_NOT_FOUND));
+		if (template.isInTrash()) {
+			throw new BusinessException(TemplateErrorCode.TEMPLATE_IN_TRASH);
+		}
+		return template;
+	}
+
 }

src/main/java/com/sniptext/domain/template/service/dto/query/TemplateDetailQuery.java

@@ -0,0 +1,7 @@
+package com.sniptext.domain.template.service.dto.query;
+
+public record TemplateDetailQuery(
+	Long userId,
+	Long templateId
+) {
+}

src/main/java/com/sniptext/domain/template/service/dto/result/TemplateDetailResult.java

@@ -0,0 +1,35 @@
+package com.sniptext.domain.template.service.dto.result;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+import com.sniptext.domain.template.entity.Template;
+import com.sniptext.domain.template.support.TemplateVariableExtractor;
+
+/** 내 템플릿 상세. 변수 목록은 저장하지 않고 본문에서 뽑는다. */
+public record TemplateDetailResult(
+	Long templateId,
+	String title,
+	String shortcut,
+	String content,
+	List<String> variables,
+	LocalDateTime lastUsedAt,
+	LocalDateTime createdAt,
+	LocalDateTime editedAt
+) {
+
+	public static TemplateDetailResult from(Template template) {
+		String content = template.getContent().getValue();
+		return new TemplateDetailResult(
+			template.getId(),
+			template.getTitle().getValue(),
+			template.getShortcut().getValue(),
+			content,
+			TemplateVariableExtractor.extract(content),
+			template.getLastUsedAt(),
+			template.getCreatedAt(),
+			template.getEditedAt()
+		);
+	}
+
+}

src/test/java/com/sniptext/domain/template/controller/TemplateDetailControllerTest.java

@@ -0,0 +1,206 @@
+package com.sniptext.domain.template.controller;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.hamcrest.Matchers.contains;
+import static org.hamcrest.Matchers.nullValue;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.header;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import java.nio.charset.StandardCharsets;
+import java.time.LocalDateTime;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Import;
+import org.springframework.http.HttpHeaders;
+import org.springframework.test.web.servlet.MvcResult;
+import org.springframework.test.web.servlet.ResultActions;
+import org.springframework.transaction.annotation.Transactional;
+
+import com.sniptext.domain.template.entity.Shortcut;
+import com.sniptext.domain.template.entity.Template;
+import com.sniptext.domain.template.entity.TemplateContent;
+import com.sniptext.domain.template.entity.TemplateTitle;
+import com.sniptext.domain.template.repository.TemplateRepository;
+import com.sniptext.domain.user.entity.User;
+import com.sniptext.fixture.TemplateFixture;
+import com.sniptext.fixture.UserFixture;
+import com.sniptext.support.IntegrationTestSupport;
+import com.sniptext.support.MutableClock;
+import com.sniptext.support.MutableClockConfiguration;
+
+import jakarta.persistence.EntityManager;
+import tools.jackson.databind.json.JsonMapper;
+
+/** 명세 9번. 본인 소유·휴지통 구분과 응답 형식을 실제 필터·MySQL까지 거쳐 확인한다. */
+@Transactional
+@Import(MutableClockConfiguration.class)
+class TemplateDetailControllerTest extends IntegrationTestSupport {
+
+	private static final String PATH = "/api/v1/templates/{templateId}";
+	private static final String NO_STORE = "no-store";
+	private static final LocalDateTime FIXED = LocalDateTime.of(2026, 10, 7, 10, 30);
+	private static final String CONTENT = "{{금액}}원입니다.\n{{고객명}}님, {{금액}}원을 확인해주세요.";
+
+	@Autowired
+	private TemplateRepository templateRepository;
+
+	@Autowired
+	private EntityManager entityManager;
+
+	@Autowired
+	private MutableClock clock;
+
+	@Autowired
+	private JsonMapper jsonMapper;
+
+	private Long userId;
+	private Long otherUserId;
+
+	@BeforeEach
+	void setUp() {
+		clock.setTo(FIXED);
+		userId = saveUser("owner@sniptext.com");
+		otherUserId = saveUser("other@sniptext.com");
+	}
+
+	@Test
+	@DisplayName("내 템플릿을 조회하면 200, 명세 순서의 필드와 +09:00이 붙은 시각, 캐시 금지 헤더")
+	void getTemplate() throws Exception {
+		Template template = templateRepository.saveAndFlush(TemplateFixture.template(userId, "/Quote"));
+		template.edit(TemplateTitle.create("프로젝트 견적 안내"), Shortcut.create("/Quote"), TemplateContent.create(CONTENT),
+			FIXED.plusHours(1));
+		template.markUsed(FIXED.plusHours(2));
+		flushAndClear();
+
+		MvcResult result = getAs(userId, template.getId())
+			.andExpect(status().isOk())
+			.andExpect(header().string(HttpHeaders.CACHE_CONTROL, NO_STORE))
+			.andExpect(jsonPath("$.isSuccess").value(true))
+			.andExpect(jsonPath("$.code").value("TEMPLATE200_2"))
+			.andExpect(jsonPath("$.message").value("템플릿 조회에 성공했습니다."))
+			.andExpect(jsonPath("$.result.templateId").value(template.getId()))
+			.andExpect(jsonPath("$.result.title").value("프로젝트 견적 안내"))
+			.andExpect(jsonPath("$.result.shortcut").value("/Quote"))
+			.andExpect(jsonPath("$.result.content").value(CONTENT))
+			.andExpect(jsonPath("$.result.lastUsedAt").value("2026-10-07T12:30:00+09:00"))
+			.andExpect(jsonPath("$.result.createdAt").value("2026-10-07T10:30:00+09:00"))
+			.andExpect(jsonPath("$.result.editedAt").value("2026-10-07T11:30:00+09:00"))
+			.andReturn();
+
+		assertThat(jsonMapper.readTree(result.getResponse().getContentAsString(StandardCharsets.UTF_8))
+			.get("result").propertyNames())
+			.containsExactly("templateId", "title", "shortcut", "content", "variables", "lastUsedAt", "createdAt",
+				"editedAt");
+	}
+
+	@Test
+	@DisplayName("변수 목록은 복호화한 본문에서 뽑아 첫 등장 순으로 중복 없이 내려준다")
+	void variables() throws Exception {
+		Template template = templateRepository.saveAndFlush(TemplateFixture.templateWithContent(userId, CONTENT));
+		flushAndClear();
+
+		getAs(userId, template.getId())
+			.andExpect(status().isOk())
+			.andExpect(jsonPath("$.result.variables", contains("금액", "고객명")));
+	}
+
+	@Test
+	@DisplayName("사용 이력이 없으면 lastUsedAt은 null이다")
+	void neverUsed() throws Exception {
+		Template template = templateRepository.saveAndFlush(TemplateFixture.template(userId));
+		flushAndClear();
+
+		getAs(userId, template.getId())
+			.andExpect(status().isOk())
+			.andExpect(jsonPath("$.result.lastUsedAt").value(nullValue()));
+	}
+
+	@Test
+	@DisplayName("없는 템플릿이면 TEMPLATE404_1")
+	void notFound() throws Exception {
+		expectNotFound(getAs(userId, Long.MAX_VALUE));
+	}
+
+	@Test
+	@DisplayName("다른 회원의 템플릿이면 TEMPLATE404_1")
+	void otherUsersTemplate() throws Exception {
+		Template template = templateRepository.saveAndFlush(TemplateFixture.template(otherUserId));
+
+		expectNotFound(getAs(userId, template.getId()));
+	}
+
+	@Test
+	@DisplayName("내 템플릿이 휴지통에 있으면 TEMPLATE404_2")
+	void trashed() throws Exception {
+		Template template = saveTrashed(userId);
+
+		expectError(getAs(userId, template.getId()), 404, "TEMPLATE404_2", "이미 삭제된 템플릿이에요.");
+	}
+
+	@Test
+	@DisplayName("다른 회원의 휴지통 템플릿이면 TEMPLATE404_1이다 (존재 여부를 노출하지 않는다)")
+	void otherUsersTrashed() throws Exception {
+		Template template = saveTrashed(otherUserId);
+
+		expectNotFound(getAs(userId, template.getId()));
+	}
+
+	@Test
+	@DisplayName("토큰이 없으면 COMMON401_1, 캐시 금지")
+	void unauthenticated() throws Exception {
+		expectError(mockMvc.perform(get(PATH, 1L)), 401, "COMMON401_1", "로그인이 필요해요.");
+	}
+
+	@ParameterizedTest
+	@ValueSource(strings = {"abc", "99999999999999999999"})
+	@DisplayName("templateId가 Long으로 바뀌지 않으면 COMMON400_1")
+	void invalidTemplateId(String templateId) throws Exception {
+		expectError(mockMvc.perform(get("/api/v1/templates/" + templateId)
+			.header(HttpHeaders.AUTHORIZATION, bearer(userId))), 400, "COMMON400_1", "잘못된 요청입니다.");
+	}
+
+	private ResultActions getAs(Long userId, Long templateId) throws Exception {
+		return mockMvc.perform(get(PATH, templateId).header(HttpHeaders.AUTHORIZATION, bearer(userId)));
+	}
+
+	private static void expectNotFound(ResultActions actions) throws Exception {
+		expectError(actions, 404, "TEMPLATE404_1", "템플릿을 찾을 수 없어요.");
+	}
+
+	private static void expectError(ResultActions actions, int status, String code, String message) throws Exception {
+		actions.andExpect(status().is(status))
+			.andExpect(header().string(HttpHeaders.CACHE_CONTROL, NO_STORE))
+			.andExpect(jsonPath("$.isSuccess").value(false))
+			.andExpect(jsonPath("$.code").value(code))
+			.andExpect(jsonPath("$.message").value(message))
+			.andExpect(jsonPath("$.result").isEmpty());
+	}
+
+	private Template saveTrashed(Long ownerId) {
+		Template template = templateRepository.saveAndFlush(TemplateFixture.template(ownerId));
+		template.moveToTrash(FIXED);
+		flushAndClear();
+		return template;
+	}
+
+	/** 1차 캐시를 비워 응답이 DB에서 다시 읽은(복호화한) 값으로 만들어지게 한다 */
+	private void flushAndClear() {
+		entityManager.flush();
+		entityManager.clear();
+	}
+
+	private Long saveUser(String email) {
+		User user = UserFixture.user(email);
+		entityManager.persist(user);
+		entityManager.flush();
+		return user.getId();
+	}
+
+}