Getting started

<?php
// api/src/Entity/Product.php

namespace App\Entity;

use ApiPlatform\Core\Annotation\ApiResource;
use Doctrine\ORM\Mapping as ORM;
use Doctrine\Common\Collections\ArrayCollection;
use Symfony\Component\Validator\Constraints as Assert;

/**
 * @ApiResource
 * @ORM\Entity
 */
class Product // The class name will be used to name exposed resources
{
    /**
     * @ORM\Column(type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    private $id;

    /**
     * @var string $name A name property - this description will be available in the API documentation too.
     *
     * @ORM\Column
     * @Assert\NotBlank
     */
    public $name;

    // Notice the "cascade" option below, this is mandatory if you want Doctrine to automatically persist the related entity
    /**
     * @ORM\OneToMany(targetEntity="Offer", mappedBy="product", cascade={"persist"})
     */
    public $offers;

    public function __construct()
    {
        $this->offers = new ArrayCollection(); // Initialize $offers as a Doctrine collection
    }
    
    public function getId(): ?int
    {
        return $this->id;
    }

    // Adding both an adder and a remover as well as updating the reverse relation is mandatory
    // if you want Doctrine to automatically update and persist (thanks to the "cascade" option) the related entity
    public function addOffer(Offer $offer): void
    {
        $offer->product = $this;
        $this->offers->add($offer);
    }

    public function removeOffer(Offer $offer): void
    {
        $offer->product = null;
        $this->offers->removeElement($offer);
    }
    
    // ...
}

<?php
// api/src/Entity/Offer.php

namespace App\Entity;

use ApiPlatform\Core\Annotation\ApiResource;
use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Validator\Constraints as Assert;

/**
 * An offer from my shop - this description will be automatically extracted from the PHPDoc to document the API.
 *
 * @ApiResource(iri="http://schema.org/Offer")
 * @ORM\Entity
 */
class Offer
{
    /**
     * @ORM\Column(type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    private $id;

    /**
     * @ORM\Column(type="text")
     */
    public $description;

    /**
     * @ORM\Column(type="float")
     * @Assert\NotBlank
     * @Assert\Range(min=0, minMessage="The price must be superior to 0.")
     * @Assert\Type(type="float")
     */
    public $price;

    /**
     * @ORM\ManyToOne(targetEntity="Product", inversedBy="offers")
     */
    public $product;

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

# api/config/packages/api_platform.yaml
api_platform:
    mapping:
        paths: 
            - '%kernel.project_dir%/src/Entity' # default configuration for annotations
            - '%kernel.project_dir%/config/api_platform' # yaml or xml directory configuration