fix: 업로드 URL 요청의 필수 필드와 validation 계약 정렬

src/main/java/in/koreatech/koin/infrastructure/s3/dto/UploadUrlRequest.java

@@ -1,19 +1,28 @@
 package in.koreatech.koin.infrastructure.s3.dto;
 
+import static io.swagger.v3.oas.annotations.media.Schema.RequiredMode.REQUIRED;
+
 import com.fasterxml.jackson.databind.PropertyNamingStrategies.SnakeCaseStrategy;
 import com.fasterxml.jackson.databind.annotation.JsonNaming;
 
 import io.swagger.v3.oas.annotations.media.Schema;
+import jakarta.validation.constraints.NotBlank;
+import jakarta.validation.constraints.NotNull;
+import jakarta.validation.constraints.Positive;
 
 @JsonNaming(SnakeCaseStrategy.class)
 public record UploadUrlRequest(
-    @Schema(description = "파일 크기", example = "1000")
+    @Schema(description = "파일 크기", example = "1000", requiredMode = REQUIRED)
+    @NotNull(message = "파일 크기는 필수입니다.")
+    @Positive(message = "파일 크기는 0보다 커야 합니다.")
     Integer contentLength,
 
-    @Schema(description = "파일 타입", example = "image/png")
+    @Schema(description = "파일 타입", example = "image/png", requiredMode = REQUIRED)
+    @NotBlank(message = "파일 타입은 필수입니다.")
     String contentType,
 
-    @Schema(description = "파일 이름", example = "hello.png")
+    @Schema(description = "파일 이름", example = "hello.png", requiredMode = REQUIRED)
+    @NotBlank(message = "파일 이름은 필수입니다.")
     String fileName
 ) {
 

src/test/java/in/koreatech/koin/unit/infrastructure/s3/dto/UploadUrlRequestValidationTest.java

@@ -0,0 +1,124 @@
+package in.koreatech.koin.unit.infrastructure.s3.dto;
+
+import static org.hamcrest.Matchers.containsInAnyOrder;
+import static org.hamcrest.Matchers.hasSize;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+import static org.springframework.http.MediaType.APPLICATION_JSON;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+import org.springframework.core.MethodParameter;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+import org.springframework.validation.beanvalidation.LocalValidatorFactoryBean;
+import org.springframework.web.bind.support.WebDataBinderFactory;
+import org.springframework.web.context.request.NativeWebRequest;
+import org.springframework.web.method.support.HandlerMethodArgumentResolver;
+import org.springframework.web.method.support.ModelAndViewContainer;
+
+import in.koreatech.koin.domain.upload.controller.UploadController;
+import in.koreatech.koin.global.auth.Auth;
+import in.koreatech.koin.global.exception.GlobalExceptionHandler;
+import in.koreatech.koin.infrastructure.s3.dto.UploadUrlResponse;
+import in.koreatech.koin.infrastructure.s3.service.UploadService;
+
+class UploadUrlRequestValidationTest {
+
+    private final UploadService uploadService = mock(UploadService.class);
+    private MockMvc mockMvc;
+
+    @BeforeEach
+    void setUp() {
+        LocalValidatorFactoryBean validator = new LocalValidatorFactoryBean();
+        validator.afterPropertiesSet();
+        HandlerMethodArgumentResolver authResolver = new HandlerMethodArgumentResolver() {
+            @Override
+            public boolean supportsParameter(MethodParameter parameter) {
+                return parameter.hasParameterAnnotation(Auth.class);
+            }
+
+            @Override
+            public Object resolveArgument(
+                MethodParameter parameter,
+                ModelAndViewContainer mavContainer,
+                NativeWebRequest webRequest,
+                WebDataBinderFactory binderFactory
+            ) {
+                return 1;
+            }
+        };
+        mockMvc = MockMvcBuilders.standaloneSetup(new UploadController(uploadService))
+            .setControllerAdvice(new GlobalExceptionHandler())
+            .setCustomArgumentResolvers(authResolver)
+            .setValidator(validator)
+            .build();
+
+        when(uploadService.getPresignedUrl(any(), any())).thenReturn(
+            new UploadUrlResponse(
+                "https://s3.example/pre-signed",
+                "https://static.example/upload.png",
+                java.time.LocalDateTime.of(2026, 9, 2, 12, 0)
+            )
+        );
+    }
+
+    @Test
+    void 모든_필수_필드가_없으면_표준_검증_오류를_반환한다() throws Exception {
+        mockMvc.perform(post("/OWNERS/upload/url")
+                .contentType(APPLICATION_JSON)
+                .content("{}"))
+            .andExpect(status().isBadRequest())
+            .andExpect(jsonPath("$.code").value("INVALID_REQUEST_BODY"))
+            .andExpect(jsonPath("$.message").isNotEmpty())
+            .andExpect(jsonPath("$.errorTraceId").isNotEmpty())
+            .andExpect(jsonPath("$.fieldErrors").isArray())
+            .andExpect(jsonPath("$.fieldErrors", hasSize(3)))
+            .andExpect(jsonPath("$.fieldErrors[*].field", containsInAnyOrder(
+                "content_length", "content_type", "file_name")));
+    }
+
+    @ParameterizedTest
+    @ValueSource(ints = {0, -1})
+    void 파일_크기는_양수여야_한다(int contentLength) throws Exception {
+        mockMvc.perform(post("/OWNERS/upload/url")
+                .contentType(APPLICATION_JSON)
+                .content(validBody(contentLength, "image/png", "hello.png")))
+            .andExpect(status().isBadRequest())
+            .andExpect(jsonPath("$.code").value("INVALID_REQUEST_BODY"))
+            .andExpect(jsonPath("$.fieldErrors[0].field").value("content_length"))
+            .andExpect(jsonPath("$.fieldErrors[0].constraint").value("Positive"));
+    }
+
+    @Test
+    void 파일_타입과_이름은_공백일_수_없다() throws Exception {
+        mockMvc.perform(post("/OWNERS/upload/url")
+                .contentType(APPLICATION_JSON)
+                .content(validBody(1000, " ", " ")))
+            .andExpect(status().isBadRequest())
+            .andExpect(jsonPath("$.code").value("INVALID_REQUEST_BODY"))
+            .andExpect(jsonPath("$.fieldErrors", hasSize(2)))
+            .andExpect(jsonPath("$.fieldErrors[*].field", containsInAnyOrder(
+                "content_type", "file_name")));
+    }
+
+    @Test
+    void 세_필드가_유효하면_기존_업로드_URL_응답을_반환한다() throws Exception {
+        mockMvc.perform(post("/OWNERS/upload/url")
+                .contentType(APPLICATION_JSON)
+                .content(validBody(1000, "application/octet-stream", "hello.bin")))
+            .andExpect(status().isOk())
+            .andExpect(jsonPath("$.pre_signed_url").value("https://s3.example/pre-signed"));
+    }
+
+    private String validBody(Integer contentLength, String contentType, String fileName) {
+        return "{\"content_length\":%d,\"content_type\":\"%s\",\"file_name\":\"%s\"}"
+            .formatted(contentLength, contentType, fileName);
+    }
+}