✅ Singleton pattern (single instance) ✅ Complete plugin header ✅ ABSPATH security check ✅ Class-based organization ✅ Custom post type and taxonomy ✅ Admin settings page with separate view template ✅ AJAX handlers (logged-in and public) ✅ REST API endpoints ✅ Proper activation/deactivation hooks ✅ Uninstall script for cleanup ✅ Internationalization ready ✅ Conditional asset loading ✅ Security best practices

Installation

Copy this folder to wp-content/plugins/
Rename folder and files to match your plugin name
Find and replace the following:
- My_OOP_Plugin → Your_Plugin_Class_Name
- My OOP Plugin → Your plugin name
- my-oop-plugin → your-plugin-slug
- myop_ → yourprefix_
- MYOP_ → YOURPREFIX_
- https://example.com → Your website
- Your Name → Your name
Activate in WordPress admin

Structure

my-oop-plugin/
├── my-oop-plugin.php        # Main plugin file with class
├── uninstall.php             # Cleanup on uninstall
├── README.md                 # This file
├── views/                    # Template files
│   └── admin-settings.php    # Settings page template
├── assets/                   # CSS/JS files (create as needed)
│   ├── css/
│   │   ├── admin-style.css
│   │   └── style.css
│   └── js/
│       ├── admin-script.js
│       └── script.js
└── languages/                # Translation files (create as needed)

Class Structure

Singleton Pattern

My_OOP_Plugin::get_instance(); // Get single instance

Key Methods

Initialization:

__construct() - Private constructor, sets up plugin
define_constants() - Define plugin constants
init_hooks() - Register WordPress hooks
init() - Initialize functionality on init hook

Post Types & Taxonomies:

register_post_types() - Register custom post types
register_taxonomies() - Register custom taxonomies

Admin:

add_admin_menu() - Add admin menu pages
render_settings_page() - Render settings page
save_settings() - Handle form submission
get_settings() - Get plugin settings

Assets:

admin_enqueue_scripts() - Load admin assets
enqueue_scripts() - Load frontend assets

AJAX:

ajax_handler() - Handle logged-in AJAX requests
ajax_handler_nopriv() - Handle public AJAX requests
process_ajax_data() - Process AJAX data

REST API:

register_rest_routes() - Register REST endpoints
rest_permission_check() - Check permissions
rest_get_books() - GET /wp-json/myop/v1/books
rest_get_book() - GET /wp-json/myop/v1/books/{id}

Lifecycle:

activate() - Run on plugin activation
deactivate() - Run on plugin deactivation

Included Examples

Custom Post Type & Taxonomy

"Books" post type with Gutenberg support
"Genres" hierarchical taxonomy

Settings Page

Located in Settings → OOP Plugin
Separate view template (views/admin-settings.php)
Multiple field types (text, number, checkbox)
Nonce verification and sanitization

AJAX Handlers

Logged-in: wp_ajax_myop_action
Public: wp_ajax_nopriv_myop_action
Nonce verification and capability checking

REST API

GET /wp-json/myop/v1/books - List all books
GET /wp-json/myop/v1/books/{id} - Get single book
Permission callbacks
Validation and sanitization

Extending the Plugin

Add a New Method

/**
 * Your custom method
 *
 * @param string $param Parameter description
 * @return mixed
 */
private function custom_method( $param ) {
    // Your code here
}

Add a New Hook

Add to init_hooks():

add_action( 'hook_name', array( $this, 'method_name' ) );

Add a New REST Endpoint

Add to register_rest_routes():

register_rest_route(
    'myop/v1',
    '/endpoint',
    array(
        'methods'             => 'GET',
        'callback'            => array( $this, 'rest_endpoint_handler' ),
        'permission_callback' => array( $this, 'rest_permission_check' ),
    )
);

Security Checklist

ABSPATH check at top of file
Private constructor (singleton)
Prevent cloning and unserializing
Nonces for all forms
Capability checks (current_user_can)
Input sanitization (sanitize_text_field, absint)
Output escaping (esc_html, esc_attr)
AJAX nonce verification (check_ajax_referer)
REST API permission callbacks
REST API argument validation
Conditional asset loading

Advantages of OOP Pattern

✅ Organization - Related code grouped in methods ✅ Maintainability - Easy to find and modify functionality ✅ Encapsulation - Private methods protect internal logic ✅ Singleton - Prevents multiple instances ✅ Scalability - Easy to extend with new methods ✅ Testing - Methods can be tested individually

When to Use OOP vs Simple

Use OOP when:

Plugin has 10+ functions
Need organized, maintainable code
Multiple developers working on plugin
Plugin will grow over time
Need private/protected methods

Use Simple when:

Plugin has <10 functions
Simple, focused functionality
One-person project
Unlikely to grow significantly

Distribution & Auto-Updates

Enabling GitHub Auto-Updates

You can provide automatic updates from GitHub without submitting to WordPress.org:

1. Install Plugin Update Checker library:

cd your-plugin/
git submodule add https://github.com/YahnisElsts/plugin-update-checker.git

2. Add to init_hooks() method:

/**
 * Include and initialize update checker
 */
private function init_updater() {
    $updater_path = plugin_dir_path( __FILE__ ) . 'plugin-update-checker/plugin-update-checker.php';

    if ( ! file_exists( $updater_path ) ) {
        return;
    }

    require $updater_path;

    $updateChecker = YahnisElsts\PluginUpdateChecker\v5\PucFactory::buildUpdateChecker(
        'https://github.com/yourusername/your-plugin/',
        __FILE__,
        'your-plugin-slug'
    );

    $updateChecker->setBranch( 'main' );
    $updateChecker->getVcsApi()->enableReleaseAssets();
}

Then call it in init_hooks():

private function init_hooks() {
    // Existing hooks...

    // Initialize auto-updates
    $this->init_updater();
}

3. For private repos, add token to wp-config.php:

define( 'YOUR_PLUGIN_GITHUB_TOKEN', 'ghp_xxxxxxxxxxxxx' );

Then update init_updater():

if ( defined( 'MYOP_GITHUB_TOKEN' ) ) {
    $updateChecker->setAuthentication( MYOP_GITHUB_TOKEN );
}

4. Create releases:

# Update version in plugin header
git add my-oop-plugin.php
git commit -m "Bump version to 1.0.1"
git tag 1.0.1
git push origin main
git push origin 1.0.1

# Create GitHub Release with pre-built ZIP

README.md

OOP WordPress Plugin Template

Features