Return custom collection in graphQL with Api Platform using custom data provider

Question

I have a custom DTO class, and I want to return a collection of that using graphQL. With REST it works fine. I'm using Api Platform 2.6 and PHP 8.2 There is my DTO class :

<?php

declare(strict_types=1);

namespace App\Dto;

use ApiPlatform\Core\Annotation\ApiProperty;
use ApiPlatform\Core\Annotation\ApiResource;

#[ApiResource(
    collectionOperations: [
        'get' => [
            'method' => 'GET',
            'path' => '/settings',
        ],
    ],
    itemOperations: [
        'get' => [
            'method' => 'GET',
            'path' => '/settings/{key}',
        ],
    ],
    routePrefix: '/admin',
)]
final class SettingDto
{
    #[ApiProperty(identifier: true)]
    public string $key;

    public string $value;
}

There is my custom data provider :

<?php

declare(strict_types=1);

namespace App\Api\DataProvider;

use ApiPlatform\Core\DataProvider\CollectionDataProviderInterface;
use ApiPlatform\Core\DataProvider\ItemDataProviderInterface;
use ApiPlatform\Core\DataProvider\RestrictedDataProviderInterface;
use App\Dto\SettingDto;
use Symfony\Component\DependencyInjection\ParameterBag\ParameterBagInterface;
use Symfony\Component\PropertyAccess\PropertyAccessorInterface;

final readonly class SettingDataProvider implements ItemDataProviderInterface, CollectionDataProviderInterface, RestrictedDataProviderInterface
{
    public function __construct(
        private ParameterBagInterface $parameterBag,
        private PropertyAccessorInterface $propertyAccessor,
    )
    {}

    public function supports(string $resourceClass, string $operationName = null, array $context = []): bool
    {
        return is_a($resourceClass, SettingDto::class, true);
    }

    /**
     * @inheritDoc
     */
    public function getCollection(string $resourceClass, string $operationName = null): array
    {
        return array_map(static function ($key, $value) {
            $settingDto = new SettingDto();
            $settingDto->key = $key;
            $settingDto->value = $value;

            return $settingDto;
        }, array_keys($this->parameterBag->get('exposed.parameters')), $this->parameterBag->get('exposed.parameters'));
    }

    public function getItem(string $resourceClass, $id, string $operationName = null, array $context = []): ?SettingDto
    {
        $setting = $this->propertyAccessor->getValue($this->parameterBag->get('exposed.parameters'), "[$id]");
        if (null === $setting) {
            return null;
        }

        $settingDto = new SettingDto();
        $settingDto->key = $id;
        $settingDto->value = $setting;

        return $settingDto;
    }
}

It works fine using REST but when I try to use graphQL I have this error :

Collection returned by the collection data provider must implement ApiPlatform\\Core\\DataProvider\\PaginatorInterface or ApiPlatform\\Core\\DataProvider\\PartialPaginatorInterface

I have also tried to use custom resolver like mentioned here instead but it's not working either. Any ideas?

Answer 1

I've finally found a solution, I used ArrayPaginator, and I've done some changes in my DTO too, so now I have my pagination back (and in REST too) :

<?php

declare(strict_types=1);

namespace App\Dto;

use ApiPlatform\Core\Annotation\ApiProperty;
use ApiPlatform\Core\Annotation\ApiResource;

#[ApiResource(
    collectionOperations: [
        'get' => [
            'method' => 'GET',
            'path' => '/settings',
        ],
    ],
    graphql: [
        'item_query',
        'collection_query' => [
            'pagination_type' => 'page',
        ],
    ],
    itemOperations: [
        'get' => [
            'method' => 'GET',
            'path' => '/settings/{key}',
        ],
    ],
    routePrefix: '/admin',
)]
final class SettingDto
{
    #[ApiProperty(identifier: true)]
    public string $key;

    public string $value;
}

And my dataProvider :

<?php

declare(strict_types=1);

namespace App\Api\DataProvider;

use ApiPlatform\Core\DataProvider\ArrayPaginator;
use ApiPlatform\Core\DataProvider\ContextAwareCollectionDataProviderInterface;
use ApiPlatform\Core\DataProvider\ItemDataProviderInterface;
use ApiPlatform\Core\DataProvider\RestrictedDataProviderInterface;
use App\Dto\SettingDto;
use Symfony\Component\DependencyInjection\ParameterBag\ParameterBagInterface;
use Symfony\Component\PropertyAccess\PropertyAccessorInterface;

final readonly class SettingDataProvider implements ItemDataProviderInterface, ContextAwareCollectionDataProviderInterface, RestrictedDataProviderInterface
{
    public function __construct(
        private ParameterBagInterface $parameterBag,
        private PropertyAccessorInterface $propertyAccessor,
    )
    {}

    public function supports(string $resourceClass, string $operationName = null, array $context = []): bool
    {
        return is_a($resourceClass, SettingDto::class, true);
    }

    /**
     * @inheritDoc
     */
    public function getCollection(string $resourceClass, string $operationName = null, array $context = []): ArrayPaginator
    {
        $page = $this->propertyAccessor->getValue($context, "[filters][page]") ?? 1;
        $itemsPerPage = $this->propertyAccessor->getValue($context, "[filters][itemsPerPage]") ?? 10;
        $firstResult = ($page -1) * $itemsPerPage;

        $settings = array_map(static function ($key, $value) {
            $settingDto = new SettingDto();
            $settingDto->key = $key;
            $settingDto->value = $value;

            return $settingDto;
        }, array_keys($this->parameterBag->get('exposed.parameters')), $this->parameterBag->get('exposed.parameters'));

        return new ArrayPaginator($settings, $firstResult, $itemsPerPage);
    }

    public function getItem(string $resourceClass, $id, string $operationName = null, array $context = []): ?SettingDto
    {
        $setting = $this->propertyAccessor->getValue($this->parameterBag->get('exposed.parameters'), "[$id]");
        if (null === $setting) {
            return null;
        }

        $settingDto = new SettingDto();
        $settingDto->key = $id;
        $settingDto->value = $setting;

        return $settingDto;
    }
}