fix: treat an empty @uploadedfiles array as missing when the parameter is required

A multipart request that carries other fields but no file reaches the handler as an empty array
(multer sets req.files = []), not as undefined, so the required check let it through and the action
ran with no files. An absent @uploadedfile was already rejected because req.file stays undefined.

Author: suresh-saini

src/ActionParameterHandler.ts

@@ -81,6 +81,9 @@ export class ActionParameterHandler<T extends BaseDriver> {
         } else {
           if (!value) return Promise.reject(new AuthorizationRequiredError(action));
         }
+      } else if (param.type === 'files' && (isValueEmpty || (Array.isArray(value) && value.length === 0))) {
+        // a multipart request that carries other fields but no file arrives as an empty array, not as undefined
+        return Promise.reject(new ParamRequiredError(action, param));
       } else if (param.name && isValueEmpty) {
         // regular check for all other parameters // todo: figure out something with param.name usage and multiple things params (query params, upload files etc.)
         return Promise.reject(new ParamRequiredError(action, param));

test/functional/action-params.spec.ts

@@ -1138,4 +1138,18 @@ describe(``, () => {
       expect(error.response.status).toEqual(HttpStatusCodes.INTERNAL_SERVER_ERROR);
     }
   });
+
+  it('@UploadedFiles when required is used a multipart request with other fields but no file is a bad request', async () => {
+    expect.assertions(1);
+    const form = new FormData();
+    form.append('caption', 'no photos attached');
+
+    try {
+      await axios.post('/photos-with-required', form, {
+        headers: form.getHeaders(),
+      });
+    } catch (error) {
+      expect(error.response.status).toEqual(HttpStatusCodes.BAD_REQUEST);
+    }
+  });
 });