Gamajo\Registerable

Register WordPress post types and taxonomies using object-orientated design.

Description

Most implementation of registering post types and taxonomies in WordPress might use classes, but these are little more than poor namespaces. Multiple post types and taxonomies are either all registered via methods in the same class, or contain duplicate code across multiple classes. I wanted to dive into how registration could be structured using something that is closer to real OOP.

The code seen here is in working use on a live project.

Structure

The main code is under the Gamajo\Registerable namespace.

• Registerable - interface for different things that are registerable. Methods include register(), unregister(), set_args() and get_args().
• Post_Type - abstract class for registering post types. Implements Registerable, so required methods say how a post type should be registered, unregistered and how arguments should be handled. Includes abstract methods for default_args() and messages() which will contain implementation for specific post types.
• Taxonomy - abstract class for registering taxonomies. Implements Registerable, so required methods say how a taxonomy should be registered, unregistered and how arguments should be handled. Includes abstract methods for default_args() which will contain implementation for specific taxonomies. There is a little duplication here between this and Post_type - either the Registerable could be changed from an interface to an abstract class to accommodate the common method implementations, or traits could be used.

In the examples directory are some example implementations, under a made-up Gamajo\Meal_Planner namespace.

• Post_Type_{post type} e.g. Post_Type_Recipe - specific implementation of a post type, which extends Gamajo\Registerable\Post_Type. Only defines the $post_type property, and the default_args() and messages() methods.
• Taxonomy_{taxonomy} e.g. Taxonomy_Recipe_Type - specific implementation of a taxonomy, which extends Gamajo\Registerable\Taxonomy. Only defines the $taxonomy property, and the default_args() method.

If you register multiple post types and taxonomies, you can see that only multiple classes that extend the abstract classes are needed, with specific details, creating immutable objects. The boilerplate of registering, unregistering and handling arguments don't need to be repeated.

Requirements

• PHP 5.4+

Compatibility

This project is an updated version of https://github.com/GaryJones/Gamajo-Registerable, so if you need PHP 5.2 support, use that instead. The end result should be the same, but it doesn't come with namespaces, short array syntax or composer / PSR-4 support.

Installation

This isn't a WordPress plugin on its own, so the usual instructions don't apply. Instead:

1. Copy the gamajo files into your plugin, either manually, or via Composer.
2. Ensure the classes and interfaces are available. You can require_once each file, if the structural element doesn't exist, or just use an autoloader (renaming anything as needed if following PSR-4).

Usage

The examples files are examples - concrete objects of a post type and taxonomy. The only thing you need to populate for each new post type or taxonomy are the default args, and the messages. At this point, we've only created a specific post type or taxonomy class - since the class isn't instantiated, WordPress won't actually register anything.

Once the classes exist, instantiating can be done with something like:

add_action( 'init', 'prefix_mealplanner' );
/**
 * Kickstart the Meal Planner plugin.
 */
function prefix_mealplanner() {
	// Register Recipe Type taxonomy.
	require plugin_dir_path( __FILE__ ) . 'src/Taxonomy_Recipe_Type.php'; // Or use an autoloader.
	global $prefix_taxonomy_recipe_type;
	$prefix_taxonomy_recipe_type = new Gamajo\MealPlanner\Taxonomy_Recipe_Type;
	$prefix_taxonomy_recipe_type->register();

	// Register Recipe post type.
	require plugin_dir_path( __FILE__ ) . 'src/Post_Type_Recipe.php'; // Or use an autoloader.
	global $prefix_post_type_recipe;
	$prefix_post_type_recipe = new Gamajo\MealPlanner\Post_Type_Recipe;
	$prefix_post_type_recipe->register();

	register_taxonomy_for_object_type( $prefix_taxonomy_recipe_type->get_taxonomy(), $prefix_post_type_recipe->get_post_type() );
}

Contribute

Issues and Pull Requests welcomed against the develop branch. All code should follow the WordPress coding standards and be fully documented.

License

MIT, so feel free to amend and use in any personal or commercial projects.

Credits

Built by Gary Jones
Copyright 2015 Gamajo Tech