Bending WordPress to your Will

This is a workshop that I presented at PHP South Africa 2017 - these slides were just the intro and the rest of the workshop was building a basic WordPress plugin.

Transcript

1. Bending WordPress To Your Will
2. Folder Structure Headers Events Plugin Development
3. wp-content/plugins/plugin-slug plugin-slug.php readme.txt Folder Structure
4. Headers /* * Plugin Name: Seriously Simple Podcasting * Version: 1.9.6 * Plugin URI: https://wordpress.org/plugins/seriously-simple-podcasting/ * Description: Podcasting the way it's meant to be. * Author: Hugh Lashbrooke * Author URI: http://www.hughlashbrooke.com/ * Requires at least: 4.0 * Tested up to: 4.2 * * Text Domain: seriously-simple-podcasting * Domain Path: /lang/ */
5. PHP call_user_func() WordPress do_action() apply_filters() Events
6. do_action( ‘hook’ ); add_action( ‘hook’, ‘my_function’ ); Events: Hooks
7. add_action( ‘init’, ‘init_function’ ); function init_function() { ... } Events: Hooks
8. add_action( ‘hook’, ‘my_function’, 10 ); Lower number == higher priority Events: Priorities
9. add_action( ‘hook’, ‘my_function’, 10, 2 ); function my_function ( $foo, $bar ) { ... } Events: Parameters
10. apply_filters( ‘filter’, $foo ); add_filter( ‘filter’, ‘my_function’ ); Filters must always return a value Events: Filters
11. add_filter( ‘body_class’, ‘my_function’ ); function my_function( $classes ) { $classes[] = ‘my-class’; return $classes; } Events: Filters
12. remove_action( ‘hook’, ‘function’ ); remove_filter( ‘filter’, ‘function’ ); Priorities must match original hook/filter Removing Hooks & Filters
13. <?php /* * Plugin Name: Google Redirect * Version: 1.0 */ add_action( ‘init’, ‘google_redirect’ ); function google_redirect () { if( isset( $_GET[‘google_redirect’] ) ) { wp_redirect( ‘http://www.google.com’, 302 ); exit; } } ?> Bringing it Together
14. Plugin Developer Info: wordpress.org/plugins/developers/ Coding Standards: codex.wordpress.org/WordPress_Coding_Standards Action Reference: codex.wordpress.org/Plugin_API/Action_Reference Plugin Template: github.com/hlashbrooke/WordPress-Plugin-Template Helpful Links
15. https://github.com/hlashbrooke/Post-View-Counter Demo Plugin
16. automattic.com make.wordpress.org hugh.blog @hlashbrooke