PHP code example of chemisus / graphql

    
        
<?php
require_once('vendor/autoload.php');

/* Start to develop here. Best regards https://php-download.com/ */

    

chemisus / graphql example snippets

class BookWirer implements Wirer {
    function wire(Document $document) {
        $document->coerce('Book', new CallbackCoercer(function (Node $node, Book $value) {
            return (object)[
                'id' => $book->getId(),
                'title' => $book->getTitle(),
                'authorId' => $book->getAuthorId(),
            ];
        });
    }
}

class PersonWirer implements Wirer {
    function wire(Document $document) {
        $document->coerce('Person', new CallbackCoercer(function (Node $node, Person $value) {
            return (object)[
                'id' => $person->getId(),
                'name' => $person->getName(),
            ];
        });
    }
}

class QueryBookWirer implements Wirer {
    function wire(Document $document) {
        $document->fetcher('Query', 'book', new CallbackFetcher(function (Node $node) {
            $ids = $node->arg('id');
            return [BookRepository::getBook($id)];
        });

        $document->resolve('Query', 'book', new CallbackResolver(function (Node $node, $parent, $value) {
            $books = $node->getItems();
            return array_shift($books);
        });
    }
}

class QueryBooksWirer implements Wirer {
    function wire(Document $document) {
        $document->fetcher('Query', 'books', new CallbackFetcher(function (Node $node) {
            $ids = $node->arg('ids', []);
            return count($ids) ? BookRepository::getBooks($ids) : [];
        });

        $document->resolve('Query', 'books', new CallbackResolver(function (Node $node, $parent, $value) {
            return $node->getItems();
        });
    }
}

class BookAuthorWirer implements Wirer {
    function wire(Document $document) {
        $document->fetch('Book', 'author', new CallbackFetcher(function (Node $node) {
            $mapBookToAuthorId = function (Book $book) {
                return $book->getAuthorId();
            };
            $ids = array_map($mapBookToAuthorId, $node->getParent()->getItems());
            return count($ids) ? PersonRepository::getPersons($ids) : [];
        });

        $document->resolve('Book', 'author', new CallbackResolver(function (Node $node, Book $book, $value) {
            $filterAuthorById = function ($authorId) {
                return function (Person $person) use ($authorId) {
                    return $person->id === $authorId;
                };
            };
            $authors = array_filter($node->getParent()->getItems(), $filterAuthorById($book->getAuthorId())
            return $node->getItems();
        });
    }
}

class GraphQLRunner {
    /**
     * @param string $source
     * @param array $variables
     * @param Wirer[] $wirers
     */
    public function run (
        string $source,
        array $queryVariables,
        $wirers
    ) {
        // 1. load
        $documentBuilder = new DocumentBuilder();
        $documentBuilder->loadSource($source);
        $documentBuilder->loadVariables($queryVariables)
        
        // 2. build
        $document = $documentBuilder->buildDocument();
    
        // 3. wire
        $introspectionWirer = new IntrospectionWirer();
        $introspectionWirer->wire($document);
    
        foreach($wirers as $wirer) {
            $wirer->wire($document);
        }    
    
        // 4. execute    
        $documentExecutor = new DocumentExecutor();
        $data = $documentExecutor->execute($document);
        
        return $data;
    }
}

$schemaSource = "type Query { ... }";
$querySource = "query Query { ... }";
$source = implode(PHP_EOL, [$schemaSource, $querySource]);

$variables = ['param1' => 'value1'];
$wirers = [
    new BookWirer(),
    new PersonWirer(),
    new QueryBookWirer(),
    new QueryBooksWirer(),
    new BookAuthorWirer(),
];

$graphql = new GraphQLRunner();
$data = $graphql->run($source, $variables, $wirers)

†: in php, of course