# Description of Changes Please provide a summary of the changes, including: - **What was changed** - Updated `SignPDFWithCertRequest` to use `Boolean` for `showSignature` and `showLogo`, and made `pageNumber` nullable. - In `CertSignController`: - Added an `@InitBinder` to convert empty multipart fields to `null`. - Extended `@PostMapping` to consume both `multipart/form-data` and `application/x-www-form-urlencoded`. - Wrapped `pageNumber` calculation in a null-check (`pageNumber = request.getPageNumber() != null ? request.getPageNumber() - 1 : null`). - Changed signature-visualization and logo checks to `Boolean.TRUE.equals(...)` to avoid unboxing NPE. - Cleaned up imports and schema annotations in the request model. - **Why the change was made** - Prevent a 500 Internal Server Error caused by calling `.intValue()` on a null `pageNumber` when `showSignature=false` (invisible signatures). - Ensure that omitting `pageNumber` doesn’t break clients using the “try it out” swagger UI or `curl`-based requests. - **Any challenges encountered** - Configuring Spring’s data binder to treat empty file inputs as `null` required a custom `PropertyEditorSupport`. - Balancing backward compatibility with stricter type handling (switching from primitive `boolean` to boxed `Boolean`). Closes #3459 --- ## Checklist ### General - [x] I have read the [Contribution Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md) - [x] I have read the [Stirling-PDF Developer Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md) (if applicable) - [ ] I have read the [How to add new languages to Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md) (if applicable) - [x] I have performed a self-review of my own code - [x] My changes generate no new warnings ### Documentation - [ ] I have updated relevant docs on [Stirling-PDF's doc repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/) (if functionality has heavily changed) - [ ] I have read the section [Add New Translation Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md#add-new-translation-tags) (for new translation tags only) ### UI Changes (if applicable) - [ ] Screenshots or videos demonstrating the UI changes are attached (e.g., as comments or direct attachments in the PR) ### Testing (if applicable) - [ ] I have tested my changes locally. Refer to the [Testing Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md#6-testing) for more details.