fix(web): map missing multipart parts to bad request

common-web/src/test/java/com/baiyue/common/web/GlobalExceptionHandlerTest.java

@@ -18,6 +18,7 @@ import org.springframework.http.HttpStatus;
 import org.springframework.web.server.ResponseStatusException;
 import org.springframework.dao.CannotAcquireLockException;
 import org.springframework.web.multipart.MaxUploadSizeExceededException;
+import org.springframework.web.multipart.support.MissingServletRequestPartException;
 
 import java.lang.reflect.Method;
 
@@ -65,6 +66,17 @@ class GlobalExceptionHandlerTest {
         assertThat(response.getBody().code()).isEqualTo(ResultCode.BAD_REQUEST.code());
     }
 
+    @Test
+    void missingRequiredMultipartPartMapsToBadRequest() {
+        MockHttpServletRequest request = new MockHttpServletRequest();
+
+        var response = handler.handleBadRequest(
+                new MissingServletRequestPartException("file"), request);
+
+        assertThat(response.getStatusCode().value()).isEqualTo(200);
+        assertThat(response.getBody().code()).isEqualTo(ResultCode.BAD_REQUEST.code());
+    }
+
     @Test
     void validationDetailsAreIncludedInMessageAndData() {
         MockHttpServletRequest request = new MockHttpServletRequest();