How to use database in PowerDI

Understanding the databases in PowerDI

The database API in PowerDI is similar to Spring Data JPA.

Entities

Entities are the classes that represent the tables in the database. They are annotated with the @Entity annotation.

<?php

namespace App\Entities;

use PowerDI\Database\Entity;
use PowerDI\Database\SQL\Table;

#[Entity] // This annotation is used to define that this class is an entity
#[Table("users")] // This annotation is used to define the table name
class User implements \JsonSerializable {
    #[ID] // This annotation is used to define the primary key
    private ?int $id;
    private ?string $email;
    private ?string $password;
    private ?string $fullname;

    /**
     * @param ?string $email
     * @param ?string $password
     * @param ?string $fullname
     */
    public function __construct(?string $email = null, ?string $password = null, ?string $fullname = null) {
        $this->id = null;
        $this->email = $email;
        $this->password = $password;
        $this->fullname = $fullname;
    }

    public function getId(): ?int {
        return $this->id;
    }

    public function getEmail(): string {
        return $this->email;
    }

    public function getPassword(): string {
        return $this->password;
    }

    public function getFullname(): string {
        return $this->fullname;
    }

    /**
     * @param string|null $password
     */
    public function setPassword(?string $password): void {
        $this->password = $password;
    }
}

Repositories

Repositories are the classes that interact with the database. They are annotated with the @Repository annotation.

Note that there are multiple types of repositories in PowerDI, the most common one is the SqlRepository.

<?php

namespace App\Repositories;

use App\Entities\User;
use PowerDI\Database\DatabaseException;
use PowerDI\Database\Repository;
use PowerDI\Database\SQL\Query\SQLQueryBuilder;
use PowerDI\Database\SQL\Query\WhereOperators;
use PowerDI\Database\SQL\SqlRepository;

#[Repository(User::class)] // This annotation is used to define that this class is a repository and the entity it manages
class UserRepository extends SqlRepository {
    public function getUsers(): array {
        return $this->findAll();
    }

    /**
     * @throws DatabaseException
     */
    public function getUserByEmail(string $email): ?User {
        $query = (new SQLQueryBuilder( $this->class))->select(["*"])->where("email", WhereOperators::Equal, $email)->build();
        return $this->get($query->query, $query->arguments);
    }

    public function getUserById(int $id): ?User {
        return $this->find($id);
    }
}

Using the database

Connecting to the database

To connect to the database, you need to define the Connector (specific to the database you are using) and the EntityManager.

The Connector is used to connect to the database and execute queries. The EntityManager is used to manage the entities and repositories.

parameters: # The injectable properties
  db:
    default:
      dsn: "mysql:host={DB_HOST};dbname={DB_NAME}" # {VARIABLE} will be replaced by the environment variable specified in the .env file
      user: "{DB_USER}"
      password: "{DB_PASS}"
services:
  MySQLConnector: # Name of the service
    class: PowerDI\Database\MySQLConnector
    arguments: [ "%db.default.dsn%", "%db.default.username%", "%db.default.password%" ]
  EntityManager:
    class: PowerDI\Database\EntityManager
    arguments: [ "@MySQLConnector" ]
    instantiate: "always" # Instantiate the service always

Using the repositories

To use the repositories, you need to inject them into the classes where you want to use them.

<?php

namespace App\Services;

use App\Entities\User;
use App\Repositories\UserRepository;
use PowerDI\Core\Autowired;

class UserService {
    #[Autowired("@UserRepository")] // This annotation is used to inject the UserRepository
    private UserRepository $userRepository;

    public function getUserByEmail(string $email): ?User {
        return $this->userRepository->getUserByEmail($email);
    }
}