Certification fields for Certificate plugin
certificateelement_mucertify
A certificate element sub-plugin for `tool_certificate` (Moodle Workplace) that renders certification-related fields on PDF certificates. It supports displaying certification name, ID number, URL, date fields (certified, from, until) with configurable date formats, and custom fields from the `tool_mucertify` certification handler. The plugin extends `\tool_certificate\element` and provides form elements for configuring which certification field to display, preview rendering for the certificate editor, and final PDF rendering with proper output sanitization.
This plugin is exemplary in its adherence to Moodle security and coding standards.
Security: All user-facing output is properly sanitized:
format_string()for certification namess()for ID numbers\moodle_url+\html_writer::link()for URLsuserdate()viaget_string()for date formattingexport_value()from core custom field API (which internally usesformat_text()/format_string())
Architecture: The plugin correctly delegates access control to its parent tool_certificate framework. Form handling uses MoodleQuickForm (automatic CSRF protection). No direct database queries, no file system access, no external HTTP requests, no code execution functions.
Code quality: Clean, well-documented code with comprehensive test coverage (PHPUnit unit tests and Behat acceptance tests). The Privacy API is properly implemented with null_provider. Language strings are used consistently for all user-visible text.
The only observation is a minor URL path inconsistency between the preview and render methods (missing .php extension in the preview URL), which is cosmetic and has no security or functional impact.
No critical, high, medium, or low findings were identified.
Plugin Overview
certificateelement_mucertify is a lightweight certificate element sub-plugin that renders certification fields on PDF certificates generated by tool_certificate (Moodle Workplace). It is part of the MuTMS plugin suite.
Scope of Review
Files reviewed:
classes/element.php— Main element class (387 lines)classes/privacy/provider.php— Privacy API null provider (39 lines)lang/en/certificateelement_mucertify.php— Language stringsversion.php— Version and dependency declarationstests/phpunit/element_test.php— PHPUnit tests (486 lines)tests/behat/management.feature— Behat acceptance tests (98 lines)composer.json— Composer metadata
Key Findings
The plugin is clean and well-written with no security vulnerabilities identified. All output is properly sanitized using appropriate Moodle APIs (format_string(), s(), \moodle_url, \html_writer, userdate(), export_value()). The plugin delegates access control to its parent tool_certificate framework, which is the correct pattern for certificate element sub-plugins.
The codebase includes comprehensive test coverage with both PHPUnit and Behat tests covering all major functionality paths including element creation, editing, previewing, and PDF rendering.
No third-party libraries are bundled. No deprecated APIs are used.
Findings
The get_preview() method constructs a certification URL without the .php extension, while the render() method constructs the same URL with the .php extension. This inconsistency means one of the two URLs may produce a 404 when clicked.
This is a cosmetic issue affecting only the link displayed on certificates — it has no security implications.
No risk. This is a minor cosmetic inconsistency. If the preview URL is incorrect, clicking it in the certificate editor preview would result in a 404, but this does not affect the actual issued certificate PDFs (which use the render() method with the .php extension). No security impact.
The get_preview() method renders a sample certification URL shown during certificate template editing (drag-and-drop preview). The render() method generates the actual URL embedded in issued PDF certificates. Both should point to the same page endpoint.
$url = new \moodle_url('/admin/tool/mucertify/catalogue/certification', ['id' => 1]);
Ensure both URLs use the same path. If the target page is certification.php, update the preview URL:
$url = new \moodle_url('/admin/tool/mucertify/catalogue/certification.php', ['id' => 1]);
$url = new \moodle_url('/admin/tool/mucertify/catalogue/certification.php', ['id' => $data->certificationid]);
The plugin has comprehensive test coverage including both PHPUnit tests (tests/phpunit/element_test.php, 486 lines covering all public methods) and Behat acceptance tests (tests/behat/management.feature, two scenarios covering standard and custom field element management). This is notable for a plugin of this size.
The plugin correctly implements \core_privacy\local\metadata\null_provider since it does not store any personal data itself — all certificate issue data is managed by the parent tool_certificate plugin.
The decode_certificationfield_data() method handles backward compatibility with two legacy data formats (plain string field names and a dateitem/dateformat JSON structure), demonstrating careful upgrade path handling.
The deliberate use of \core_customfield\api::get_instance_fields_data() (bypassing handler visibility checks, noted in the code comment on line 371) is an appropriate design choice for certificate rendering, where the admin has explicitly chosen which field to display regardless of visibility settings.