Repositories

The Repository pattern serves as an abstraction layer between your application’s business logic and the data persistence layer. In a WordPress environment, repositories help you decouple your business logic from raw wpdb calls or Eloquent queries, making your plugin’s codebase cleaner and more maintainable.

WpMVC provides a powerful Base Repository that standardizes common database operations, ensuring your data access logic is consistent and reusable.

Why Use Repositories?

Decoupling: Controllers remain agnostic of how data is fetched or persisted.
Consistency: Standardized methods for CRUD operations across your entire plugin.
Automatic Processing: Built-in handling for complex data types like arrays and objects (JSON encoding).
Testability: Simplifies mocking data layers during unit testing.

The Base Repository

WpMVC includes an abstract WpMVC\Repositories\Repository class that provides a suite of helper methods. When you extend this class, you only need to implement the get_query_builder() method.

Base Repository Methods

By extending the base repository, your class automatically gains the following methods:

Method	Description
`create( DTO $dto )`	Inserts a new record and returns the ID.
`update( DTO $dto )`	Updates a record by its ID (retrieved from the DTO).
`get_by( $column, $value )`	Retrieves the first record matching a criteria.
`get_by_id( $id )`	Retrieves a single record by its primary key.
`get_by_ids( array $ids )`	Retrieves multiple records by their IDs.
`delete_by( $col, $val )`	Deletes records matching a criteria.
`delete_by_id( $id )`	Deletes a record by its ID.

Implementing a Repository

To create a repository, extend the base Repository class and define your query builder. Usually, this builder comes from an Eloquent model or a specific table.

Generating Repositories

Use the make:repository Artisan command to generate a new repository class:


php artisan make:repository PostRepository

The new class will be placed in your app/Repositories directory:


<?php
 
namespace MyPluginNamespace\App\Repositories;
 
defined( 'ABSPATH' ) || exit;
 
use MyPluginNamespace\WpMVC\Repositories\Repository;
use MyPluginNamespace\WpMVC\Database\Query\Builder;
use MyPluginNamespace\App\Models\Post;
 
class PostRepository extends Repository
{
    /**
     * Define the query builder instance for this repository.
     */
    public function get_query_builder(): Builder
    {
        return Post::query();
    }
 
    /**
     * Custom method: Get all published posts.
     */
    public function get_published()
    {
        return $this->get_query_builder()
            ->where( 'post_status', 'publish' )
            ->get();
    }
}

Automatic JSON Encoding: The base repository’s process_values method automatically detects arrays or objects in your data and encodes them using wp_json_encode before saving to the database.

Integration with DTOs

WpMVC repositories are designed to work with Data Transfer Objects (DTOs). This ensures that the data passed to your repository is structured and validated.


<?php
 
namespace MyPluginNamespace\App\Http\Controllers;
 
defined( 'ABSPATH' ) || exit;
 
use MyPluginNamespace\App\DTO\PostDTO;
use MyPluginNamespace\WpMVC\Routing\Response;
 
class PostController extends Controller
{
    public function store( PostDTO $dto )
    {
        // The create method accepts a DTO and handles the insertion logic
        $id = $this->posts->create( $dto );
        
        return Response::send( [ 'id' => $id ], 201 );
    }
}

Repository Injection

You can inject your repositories directly into controllers using WpMVC’s Dependency Injection.


<?php
 
namespace MyPluginNamespace\App\Http\Controllers;
 
defined( 'ABSPATH' ) || exit;
 
use MyPluginNamespace\App\Repositories\PostRepository;
use MyPluginNamespace\WpMVC\Routing\Response;
 
class PostController extends Controller
{
    protected $posts;
 
    public function __construct( PostRepository $posts )
    {
        $this->posts = $posts;
    }
 
    public function index()
    {
        return Response::send( $this->posts->get_by_id( 1 ) );
    }
}

For maximum flexibility, you can bind an interface to your repository implementation in a Service Provider.


<?php
 
namespace MyPluginNamespace\App\Providers;
 
defined( 'ABSPATH' ) || exit;
 
use MyPluginNamespace\WpMVC\Foundation\Support\Providers\ServiceProvider;
use MyPluginNamespace\App\Contracts\PostRepositoryInterface;
use MyPluginNamespace\App\Repositories\PostRepository;
 
class RepositoryServiceProvider extends ServiceProvider
{
    public function register()
    {
        $this->app->bind(
            PostRepositoryInterface::class,
            PostRepository::class
        );
    }
}