Certificate Verification System

A comprehensive WordPress plugin for managing and verifying certificates issued to students.

Features

• Certificate Management: Add, view, and delete certificates from WordPress admin
• Public Verification: Allow visitors to verify certificates using unique certificate IDs
• Security: Built-in nonce verification, input sanitization, and rate limiting
• AJAX-Powered: Smooth verification process without page reloads
• Responsive Design: Mobile-friendly verification form
• Status Management: Support for active, revoked, and expired certificates

Installation

1. Upload the certificate-verification folder to /wp-content/plugins/
2. Activate the plugin through the 'Plugins' menu in WordPress
3. Go to 'Certificates' menu in WordPress admin to start adding certificates

Usage

Adding Certificates

1. Navigate to Certificates > Add New in WordPress admin
2. Fill in the required fields:
   • Certificate ID (unique identifier)
   • Student Name
   • Issue Date
3. Optional fields:
   • Certificate Type
   • Course/Program Name
   • Expiry Date
   • Additional Information
   • Status (Active/Revoked)
4. Click "Add Certificate"

Displaying Verification Form

Add the verification form to any page or post using the shortcode:

[certificate_verification]

Shortcode Attributes

Customize the form with these optional attributes:

[certificate_verification 
    title="Custom Title" 
    description="Custom description text"
    placeholder="Enter your certificate number"
    button_text="Verify Now"
]

Managing Certificates

• View all certificates: Certificates > All Certificates
• Search certificates by ID or student name
• Delete certificates (soft delete - marks as deleted)
• Pagination for large certificate lists

Technical Details

Database Structure

The plugin creates a custom table wp_certificates with the following fields:

• id - Auto-increment primary key
• certificate_id - Unique certificate identifier
• student_name - Name of certificate recipient
• issue_date - Date certificate was issued
• certificate_type - Type of certificate
• course_name - Associated course or program
• status - Certificate status (active/revoked/deleted)
• expiry_date - Optional expiration date
• additional_info - Additional notes
• created_at - Record creation timestamp
• updated_at - Last update timestamp

Security Features

• Nonce Verification: All AJAX requests verified with WordPress nonces
• Input Sanitization: All user inputs sanitized before database operations
• Prepared Statements: SQL injection prevention through WordPress $wpdb
• Rate Limiting: IP-based rate limiting (10 requests per 15 minutes by default)
• Capability Checks: Admin functions restricted to users with 'manage_options'

AJAX Endpoints

• verify_certificate - Public endpoint for certificate verification

Development

File Structure

certificate-verification/
├── certificate-verification.php (Main plugin file)
├── includes/
│   ├── class-database.php (Database operations)
│   ├── class-admin.php (Admin interface)
│   ├── class-public.php (Public shortcode)
│   ├── class-ajax-handler.php (AJAX processing)
│   └── class-security.php (Security functions)
├── admin/
│   ├── css/
│   └── js/
├── public/
│   ├── css/
│   │   └── public-style.css
│   └── js/
│       └── public-script.js
└── README.md

Hooks and Filters

The plugin provides several hooks for customization:

• cert_verify_before_insert - Before certificate insertion
• cert_verify_after_insert - After certificate insertion
• cert_verify_verification_result - Filter verification result

Requirements

• WordPress 5.0 or higher
• PHP 7.4 or higher
• MySQL 5.6 or higher

Changelog

Version 1.0.5 (2026-01-13) - Data Preservation Update

• IMPORTANT: Certificate data now preserved when plugin is deleted
• Modified uninstall.php to keep certificate table intact
• Allows safe testing, reinstallation, and migration
• Only plugin settings and cache are removed on deletion
• Certificates remain in database permanently unless manually deleted

Version 1.0.4 (2026-01-13) - JavaScript Localization Fix

• Fixed JavaScript variable name mismatch (certVerify → certVerifier)
• Resolved "certVerifier is not defined" error
• AJAX verification now works correctly
• Form submission functional
• Loading states working properly
• All features fully operational

Version 1.0.3 (2026-01-13) - HTML Class Name Update

• Fixed HTML class names to match JavaScript selectors
• Updated form template from cert-verify- to cert-verifier-
• Form submission now properly intercepted by JavaScript
• Resolved verification form not responding to clicks

Version 1.0.2 (2026-01-13) - Database Enhancement

• Enhanced database error handling and logging
• Auto-creates database table if missing
• Fixed dbDelta compatibility (removed IF NOT EXISTS)
• Better error messages for debugging
• More specific error reporting in admin
• Fixed DEFAULT CURRENT_TIMESTAMP syntax for strict mode

Version 1.0.1 (2026-01-13) - Admin Interface Fix

• Fixed admin page slugs (cert-verify- → cert-verifier-)
• Updated all internal navigation links
• Added success/error message displays
• Fixed form submission redirects
• Fixed "Add New" and "Cancel" button links
• Certificate addition now works correctly

Version 1.0.0 (2026-01-13) - Initial Release

• Basic certificate management (Add, View, Delete)
• Public verification form via shortcode
• AJAX-powered verification
• Rate limiting (10 attempts per 15 minutes)
• Security features (nonces, sanitization, prepared statements)
• Responsive design
• Mobile-friendly interface
• Status management (Active, Revoked)
• Search functionality
• Pagination support

Support

For support and feature requests, please contact the plugin author.

License

GPL v2 or later