The document provides 10 rules for building better WordPress applications. The rules include: 1. Do not write application logic in functions.php. 2. Every action should be hooked properly using add_action(). 3. Leverage the WordPress core functionality like custom post types and user meta. 4. Use plugin dependencies to ensure required plugins are installed. 5. Standardize code following WordPress and PHP coding standards. 6. Choose an appropriate PHP version depending on needed features. 7. Avoid global scoping by using closures and namespaces. 8. Define activation and uninstall hooks to handle data and plugin setup/cleanup. 9. Turn on WP_DEBUG for testing and

1. Building better WordPress applications
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@PHILL_BROWN

2. Problems with WordPress applications
• Business logic in themes
• Repeated code
• Tight coupling
• Portability

3. Rule #1
Do not write your application in
functions.php

4. Decoupling plugins and themes
Logic Templates
Templates
Plugin
Theme

5. Rule #2
Every action should be hooked

6. function my_plugin_start() {
// Fire up application
}
// Wrong
my_plugin_start();
// Right
add_action( ‘plugins_loaded’, ‘my_plugin_start’ );

7. Rule #3
Use WordPress

8. Core checklist
• Custom post types and post meta
• Roles, capabilities and user meta
• Options and transients
• Scheduler
• Remote HTTP

9. Rule #4
Use plugin dependencies

10. • Scribu’s Plugin Dependencies
• if ( ! class_exists( ‘plugin_x’ ) ) {
wp_die( ‘Plugin Y requires plugin x’ );
}

11. Rule #5
Standardise code

12. • WordPress coding standards:
http://codex.wordpress.org/WordPress_Coding_Standards
• PHPDoc
http://en.wikipedia.org/wiki/PHPDoc

13. Rule #6
Choose your PHP version

14. • WordPress core (v3.0+) – 5.1.1
• 5.2 – DateTime
• 5.3 – Late static binding, closures,
namespacing
• 5.4 - Traits

15. Rule #7
Avoid global scoping

16. add_action( ‘init’, function() {
// do something
} );
Closures

17. namespace wordpressmy_plugin;
class Post {}
Namespacing
class My_Plugin_Post {}
PHP 5.3
PHP 5.1

18. Rule #8
Activation hooks

19. register_activation_hook( __FILE__, ‘my_plugin_activate’ );
function my_plugin_activate() {
// Create tables, roles, capabilities
}
register_uninstall_hook( __FILE__, ‘my_plugin_uninstall’ );
function my_plugin_uninstall() {
// Cleanup data
}

20. Rule #9define( ‘WP_DEBUG’, true );

21. Rule #10
Release your code

22. Questions?
@PHILL_BROWN
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