API Platform et Event Sourcing avec Ecotone

#[ApiResource(
    operations: [
        new Get(
            provider: BookItemProvider::class,
        ),
    ],
)]
class Book

symfony new bookstore
composer req api ecotone/symfony-bundle ecotone/pdo-event-sourcing ecotone/jms-converter

// services/shared.yaml
services:
    _defaults:
        autowire: true
        autoconfigure: true

    App\Shared\:
        resource: '../../src/Shared'
        exclude:
            - '../../src/Shared/Infrastructure/Kernel.php'

    Enqueue\Dbal\DbalConnectionFactory:
        factory: ['Ecotone\Dbal\DbalConnection', 'create']
        arguments:
            $connection: '@Doctrine\DBAL\Connection'

<?php

namespace App\BookStore\Infrastructure\ApiPlatform\Resource;

#[ApiResource(
    shortName: 'Book',
    operations: [new Post(processor: CreateBookProcessor::class)],
)]
final class BookResource
{
    // ...
}

<?php

namespace App\BookStore\Infrastructure\ApiPlatform\State\Processor;

final readonly class CreateBookProcessor implements ProcessorInterface
{
    public function __construct(
        private CommandBusInterface $commandBus,
        private QueryBusInterface $queryBus,
    ) {
    }

    public function process(mixed $data, Operation $operation, array $uriVariables = [], array $context = []): BookResource
    {
        // Some assertions

        $command = new CreateBookCommand(
            new BookName($data->name),
            new BookDescription($data->description),
            new Author($data->author),
            new BookContent($data->content),
            new Price($data->price),
        );

        $id = $this->commandBus->dispatch($command);
        $model = $this->queryBus->ask(new FindBookQuery(new BookId($id)));

        return BookResource::fromModel($model);
    }
}

<?php

namespace App\BookStore\Domain\Model;

#[EventSourcingAggregate]
final class Book
{
    use WithAggregateVersioning;

    #[AggregateIdentifier]
    private BookId $id;
    private BookName $name;
    private BookDescription $description;
    private Author $author;
    private BookContent $content;
    private Price $price;
    private bool $deleted = false;
}

final class Book
{
    #[CommandHandler]
    public static function create(CreateBookCommand $command): array
    {
        return [
            new BookWasCreated(
                id: new BookId(),
                name: $command->name,
                description: $command->description,
                author: $command->author,
                content: $command->content,
                price: $command->price,
            ),
        ];
    }
}

final class Book
{
    #[EventSourcingHandler]
    public function applyBookWasCreated(BookWasCreated $event): void
    {
        $this->id = $event->id();
        $this->name = $event->name;
        $this->description = $event->description;
        $this->author = $event->author;
        $this->content = $event->content;
        $this->price = $event->price;
    }
}

symfony serve

docker run --name postgres -p 5432:5432 -e POSTGRES_USER=app -e POSTGRES_PASSWORD=\!ChangeMe\! -e POSTGRES_DB=app -v database_data:/var/lib/postgresql/data postgres:15

Can't send query to App\\BookStore\\Domain\\Query\\FindBookQuery. No Query Handler defined for it. Have you forgot to add #[QueryHandler] to method?

[
  {
    "no": 1,
    "event_id": "3a2d89a7-73a2-47ba-a3bc-866e680c252c",
    "event_name": "App\\BookStore\\Domain\\Event\\BookWasCreated",
    "payload": {"id":{"value":"133d71b1-df04-4d59-9acc-ec287c2c9074"},"name":{"value":"Stardust"},"description":{"value":"Young Tristran Thorn will do anything to win the cold heart of beautiful Victoria."},"author":{"value":"Neil Gaiman"},"content":{"value":"Worth reading"},"price":{"amount":17}},
    "metadata": {"id": "3a2d89a7-73a2-47ba-a3bc-866e680c252c", "revision": 1, "timestamp": 1680192724, "_aggregate_id": "133d71b1-df04-4d59-9acc-ec287c2c9074", "_aggregate_type": "App\\BookStore\\Domain\\Model\\Book", "_aggregate_version": 1},
    "created_at": "2023-03-30 16:12:04.000000"
  }
]

<?php

namespace App\BookStore\Infrastructure\Ecotone\Repository;

interface EventSourcedBookRepository
{
    #[Repository]
    public function findBy(BookId $bookId): ?Book;

    #[Repository]
    public function getBy(BookId $bookId): Book;

    #[Repository]
    #[RelatedAggregate(Book::class)]
    public function save(BookId $bookId, int $currentVersion, array $events): void;
}

<?php

namespace App\BookStore\Application\Query;

final readonly class FindBookQueryHandler
{
    public function __construct(private BookRepositoryInterface $repository) {}

    #[QueryHandler]
    public function __invoke(FindBookQuery $query): ?Book
    {
        return $this->repository->ofId($query->id);
    }
}

{
  "@context": "/api/contexts/Book",
  "@id": "/api/books/8381db41-1911-49d6-bce9-b303cb251ecb",
  "@type": "Book",
  "name": "Stardust",
  "description": "Young Tristran Thorn will do anything to win the cold heart of beautiful Victoria.",
  "author": "Neil Gaiman",
  "content": "Worth reading",
  "price": 17
}

<?php

namespace App\BookStore\Infrastructure\ApiPlatform\State\Provider;

final readonly class BookItemProvider implements ProviderInterface
{
    public function __construct(private QueryBusInterface $queryBus) {}

    public function provide(Operation $operation, array $uriVariables = [], array $context = []): ?BookResource
    {
        $model = $this->queryBus->ask(new FindBookQuery(new BookId($uriVariables['id'])));

        return null !== $model ? BookResource::fromModel($model) : null;
    }
}

<?php

namespace App\BookStore\Infrastructure\Ecotone\Repository;

final readonly class BookRepository implements BookRepositoryInterface
{
    public function __construct(private EventSourcedBookRepository $eventSourcedRepository) {}

    public function ofId(BookId $id): ?Book
    {
        if (!$eventSourcedBook = $this->eventSourcedRepository->findBy($id)) {
            return null;
        }

        if ($eventSourcedBook->deleted()) {
            return null;
        }

        return $eventSourcedBook;
    }
}

<?php

namespace App\BookStore\Infrastructure\Ecotone\Projection;

#[Projection('bookList', Book::class)]
final class BookIdsProjection
{
    #[EventHandler]
    public function addBook(BookWasCreated $event, #[ProjectionState] array $bookIdsState): array
    {
        $bookIdsState[] = (string) $event->id();

        return $bookIdsState;
    }

    #[EventHandler]
    public function removeBook(BookWasDeleted $event, #[ProjectionState] array $bookIdsState): array
    {
        if (false !== $index = array_search((string) $event->id(), $bookIdsState, true)) {
            unset($bookIdsState[$index]);
        }

        return array_values($bookIdsState);
    }
}

bin/console ecotone:es:initialize-projection bookList

[
  {
    "no": 1,
    "name": "bookList",
    "position": {"App\\BookStore\\Domain\\Model\\Book": 5},
    "state": ["133d71b1-df04-4d59-9acc-ec287c2c9074", "8381db41-1911-49d6-bce9-b303cb251ecb"],
    "status": "idle",
    "locked_until": null
  }
]

<?php

namespace App\BookStore\Infrastructure\Ecotone\Projection;

interface BookIdsGateway
{
    #[ProjectionStateGateway('bookList')]
    public function getBookIds(): array;
}

<?php

namespace App\BookStore\Infrastructure\ApiPlatform\State\Provider;

final readonly class BookCollectionProvider implements ProviderInterface
{
    public function __construct(private QueryBusInterface $queryBus, private Pagination $pagination) {}

    public function provide(Operation $operation, array $uriVariables = [], array $context = []): ApiPlatformPaginatorInterface|array
    {
        $offset = $limit = null;

        if ($this->pagination->isEnabled($operation, $context)) {
            $offset = $this->pagination->getPage($context);
            $limit = $this->pagination->getLimit($operation, $context);
        }

        $books = $this->queryBus->ask(new FindBooksQuery(null, $offset, $limit));

        $resources = [];
        foreach ($books as $book) {
            $resources[] = BookResource::fromModel($book);
        }

        if (null !== $offset && null !== $limit && $books instanceof PaginatorInterface) {
            return new Paginator(
                new \ArrayIterator($resources),
                (float) $books->getCurrentPage(),
                (float) $books->getItemsPerPage(),
                (float) $books->getLastPage(),
                (float) $books->getTotalItems(),
            );
        }

        return $resources;
    }
}

<?php

namespace App\BookStore\Infrastructure\ApiPlatform\OpenApi;

final class AuthorFilter implements FilterInterface
{
    public function getDescription(string $resourceClass): array
    {
        return [
            'author' => [
                'property' => 'author',
                'type' => Type::BUILTIN_TYPE_STRING,
                'required' => false,
            ],
        ];
    }
}

<?php

namespace App\BookStore\Infrastructure\ApiPlatform\Resource;

#[ApiResource(
    shortName: 'Book',
    operations: [
        new GetCollection(
            filters: [AuthorFilter::class],
            provider: BookCollectionProvider::class,
        ),
        // ...
    ],
)]
final class BookResource
{
    // ...
}

<?php

namespace App\BookStore\Application\Query;

final readonly class FindBooksQueryHandler
{
    public function __construct(private BookRepositoryInterface $bookRepository) {}

    #[QueryHandler]
    public function __invoke(FindBooksQuery $query): iterable
    {
        if (null !== $query->author) {
            return $this->bookRepository->findByAuthor($query->author);
        }

        // ...
    }
}

<?php

namespace App\BookStore\Infrastructure\Ecotone\Repository;

final readonly class BookRepository implements BookRepositoryInterface
{
    // ...

    public function findByAuthor(Author $author): iterable
    {
        $byAuthorBookIds = $this->booksByAuthorGateway->getByAuthorBookIds();

        foreach ($byAuthorBookIds[$author->value] ?? [] as $bookId) {
            if ($book = $this->ofId(new BookId($bookId))) {
                yield $book;
            }
        }
    }
}

<?php

namespace App\BookStore\Infrastructure\Ecotone\Projection;

#[Projection('booksByAuthor', Book::class)]
final class BooksByAuthorProjection
{
    #[EventHandler]
    public function addBook(BookWasCreated $event, #[ProjectionState] array $booksByAuthorState): array
    {
        return $this->addBookToAuthorBooks($event->id(), $event->author, $booksByAuthorState);
    }

    #[EventHandler]
    public function updateBook(BookWasUpdated $event, #[ProjectionState] array $booksByAuthorState): array
    {
        if (!$event->author) {
            return $booksByAuthorState;
        }

        $booksByAuthorState = $this->removeBookFromAuthorBooks($event->id(), $booksByAuthorState);

        return $this->addBookToAuthorBooks($event->id(), $event->author, $booksByAuthorState);
    }

    #[EventHandler]
    public function removeBook(BookWasDeleted $event, #[ProjectionState] array $booksByAuthorState): array
    {
        return $this->removeBookFromAuthorBooks($event->id(), $booksByAuthorState);
    }

    private function addBookToAuthorBooks(BookId $bookId, Author $author, array $booksByAuthorState): array
    {
        if (!isset($booksByAuthorState[$author->value])) {
            $booksByAuthorState[$author->value] = [];
        }

        if ($this->findBookAuthor($bookId, $booksByAuthorState)?->isEqualTo($author)) {
            return $booksByAuthorState;
        }

        $booksByAuthorState[$author->value][] = (string) $bookId;

        return $booksByAuthorState;
    }

    private function removeBookFromAuthorBooks(BookId $bookId, array $booksByAuthorState): array
    {
        $previousAuthor = $this->findBookAuthor($bookId, $booksByAuthorState);

        if (!$previousAuthor) {
            return $booksByAuthorState;
        }

        $previousBookIndex = array_search((string) $bookId, $booksByAuthorState[$previousAuthor->value], true);
        unset($booksByAuthorState[$previousAuthor->value][$previousBookIndex]);
        $booksByAuthorState[$previousAuthor->value] = array_values($booksByAuthorState[$previousAuthor->value]);

        return $booksByAuthorState;
    }

    private function findBookAuthor(BookId $bookId, array $booksByAuthorState): ?Author
    {
        foreach ($booksByAuthorState as $author => $books) {
            if (in_array((string) $bookId, $books, true)) {
                return new Author($author);
            }
        }

        return null;
    }
}

<?php

namespace App\BookStore\Domain\Event;

final readonly class BookWasDiscounted implements BookEvent
{
    public function __construct(private BookId $id, public Discount $discount) {}

    public function id(): BookId
    {
        return $this->id;
    }
}

<?php

declare(strict_types=1);

namespace App\BookStore\Domain\Command;

final readonly class DiscountBookCommand implements CommandInterface
{
    public function __construct(public BookId $id, public Discount $discount) {}
}

<?php

namespace App\BookStore\Domain\Model;

#[EventSourcingAggregate]
final class Book
{
    // ...

    #[CommandHandler]
    public function discount(DiscountBookCommand $command): array
    {
        return [new BookWasDiscounted(id: $command->id, discount: $command->discount)];
    }

    #[EventSourcingHandler]
    public function applyBookWasDiscounted(BookWasDiscounted $event): void
    {
        $this->price = $this->price->applyDiscount($event->discount);
    }
}

<?php

namespace App\BookStore\Infrastructure\ApiPlatform\State\Processor;

final readonly class DiscountBookProcessor implements ProcessorInterface
{
    public function __construct(private CommandBusInterface $commandBus, private QueryBusInterface $queryBus) {}

    public function process(mixed $data, Operation $operation, array $uriVariables = [], array $context = []): BookResource
    {
        $command = new DiscountBookCommand(new BookId($bookResource->id), new Discount($data->discountPercentage));

        $this->commandBus->dispatch($command);

        $model = $this->queryBus->ask(new FindBookQuery($command->id));

        return BookResource::fromModel($model);
    }
}

<?php

namespace App\BookStore\Infrastructure\ApiPlatform\Payload;

final readonly class DiscountBookPayload
{
    public function __construct(
        #[Assert\Range(min: 0, max: 100)]
        public int $discountPercentage,
    ) {}
}

<?php

namespace App\BookStore\Infrastructure\ApiPlatform\Resource;

#[ApiResource(
    shortName: 'Book',
    operations: [
        new Post(
            '/books/{id}/discount.{_format}',
            openapiContext: ['summary' => 'Apply a discount percentage on a Book resource.'],
            input: DiscountBookPayload::class,
            provider: BookItemProvider::class,
            processor: DiscountBookProcessor::class,
        ),
        // ...
    ],
)]
final class BookResource
{
    // ...
}

curl -X 'POST' \
  'https://localhost:8000/api/books/8381db41-1911-49d6-bce9-b303cb251ecb/discount' \
  -H 'accept: application/ld+json' \
  -H 'Content-Type: application/ld+json' \
  -d '{
  "discountPercentage": 10
}'

{
  "@context": "/api/contexts/Book",
  "@id": "/api/books/8381db41-1911-49d6-bce9-b303cb251ecb",
  "@type": "Book",
  "name": "Stardust",
  "description": "Young Tristran Thorn will do anything to win the cold heart of beautiful Victoria.",
  "author": "Neil Gaiman",
  "content": "Very good!",
  "price": 15
}

<?php

namespace App\BookStore\Infrastructure\ApiPlatform\Resource;

#[ApiResource(
    shortName: 'Book',
    operations: [
        new GetCollection(
            '/books/{id}/events.{_format}',
            openapiContext: ['summary' => 'Get events for this Book.'],
            output: BookEvent::class,
            provider: BookEventsProvider::class,
        ),
        // ...
    ],
)]
final class BookResource
{
    // ...
}

<?php

namespace App\BookStore\Infrastructure\ApiPlatform\State\Provider;

final readonly class BookEventsProvider implements ProviderInterface
{
    public function __construct(private QueryBusInterface $queryBus, private Pagination $pagination) {}

    public function provide(Operation $operation, array $uriVariables = [], array $context = []): PaginatorInterface|array
    {
        $bookEvents = $this->queryBus->ask(new FindBookEventsQuery(new BookId($uriVariables['id'])));
        $bookEvents = iterator_to_array($bookEvents);

        if ($this->pagination->isEnabled($operation, $context)) {
            $offset = $this->pagination->getPage($context);
            $limit = $this->pagination->getLimit($operation, $context);

            return new ArrayPaginator($bookEvents, ($offset - 1) * $limit, $limit);
        }

        return $bookEvents;
    }
}

<?php

namespace App\BookStore\Infrastructure\Ecotone\Repository;

final readonly class BookRepository implements BookRepositoryInterface
{
    public function __construct(
        private EventStore $eventStore,
        // ...
    ) {}

    public function findEvents(BookId $id): iterable
    {
        $matcher = (new MetadataMatcher())->withMetadataMatch(LazyProophEventStore::AGGREGATE_ID, Operator::EQUALS(), (string) $id);

        $events = $this->eventStore->load(Book::class, 1, null, $matcher);

        foreach ($events as $event) {
            yield $event->getPayload();
        }
    }
}

curl -X 'GET' \
  'https://localhost:8000/api/books/8381db41-1911-49d6-bce9-b303cb251ecb/events?page=1' \
  -H 'accept: application/ld+json'

{
  "@context": "/api/contexts/Book",
  "@id": "/api/books/8381db41-1911-49d6-bce9-b303cb251ecb/events",
  "@type": "hydra:Collection",
  "hydra:totalItems": 3,
  "hydra:member": [
    {
      "@type": "BookWasCreated",
      "@id": "/api/.well-known/genid/fa6ed43b678fef3ff6cb",
      "name": {
        "@type": "BookName",
        "@id": "/api/.well-known/genid/50a7cc505356c512bdc5",
        "value": "Stardust"
      },
      "description": {
        "@type": "BookDescription",
        "@id": "/api/.well-known/genid/c7da1d7e376e06996a94",
        "value": "Young Tristran Thorn will do anything to win the cold heart of beautiful Victoria."
      },
      "author": {
        "@type": "Author",
        "@id": "/api/.well-known/genid/76b61512ec3cd81a14f8",
        "value": "Neil Gaiman"
      },
      "content": {
        "@type": "BookContent",
        "@id": "/api/.well-known/genid/aa82af56f9c818c1af57",
        "value": "Worth reading"
      },
      "price": {
        "@type": "Price",
        "@id": "/api/.well-known/genid/8dfc424d3d584903abf5",
        "amount": 17
      }
    },
    {
      "@type": "BookWasUpdated",
      "@id": "/api/.well-known/genid/91c1db7d829e433b68ca",
      "content": {
        "@type": "BookContent",
        "@id": "/api/.well-known/genid/a874ab75731dc9aaabb9",
        "value": "Very good!"
      }
    },
    {
      "@type": "BookWasDiscounted",
      "@id": "/api/.well-known/genid/469c9c706fff0777e080",
      "discount": {
        "@type": "Discount",
        "@id": "/api/.well-known/genid/d9ce43d5500bd49c0e80",
        "percentage": 10
      }
    }
  ]
}