how to inject php GraphQL query results , with queries defined in Twig(Bridge) templates, using Twig Extension in Laravel8?

Question

I've setup a laravel 8 site, with php 7.4.

I prefer Twig frontend templating to Blade. I've installed twigbridge to enable Twig usage. Templating works great.

I've a backend app that serves up content via GraphQL.

I want to access/reference the backend content, via GraphQL query, in my Twig templates.

I've composer-installed 'PHP GraphQL Client' (https://github.com/mghoneimy/php-graphql-client) into the Laravel app.

It provides php GraphQL query access of the form:

$gql = (new Query('companies'))
    ->setSelectionSet(
        [
            'name',
            'serialNumber'
        ]
    );

To inject query results into my Laravel/Twig templates, I'm creating a TwigExtension

I'm piecing together the Extension from scattered online posts and not much documentation. So far I've got (not yet functional / WIP)

edit app/Twig/GraphqlQuery.php

    <?php

    namespace App\Twig;

    use Twig\Extension\AbstractExtension;
    use Twig\TwigFilter;

    use GraphQL\Client;
    use GraphQL\Exception\QueryError;
    use GraphQL\Query;

    class GraphqlQuery extends AbstractExtension {

        protected $client;
        protected $query;

        public function __construct(
            Client $client,
            Query  $query
        ) {
            $this->client = $client;
            $this->query  = $query;
        }

        public function getFunctions(): array {
            return [
                new TwigFunction(
                    'gql_query',
                    [$this, 'gqlQuery']
                ),
            ];
        }

        public function gqlQuery($gql_data) {

            $gql = (new Query('twig'))
                ->setVariables(
                    [
                        new Variable('name', 'String', true),
                        new Variable('limit', 'Int', false, 5)
                    ]
                )
                ->setArguments(
                    [
                        'name' => '$name',
                        'first' => '$limit'
                    ]
                )
                ->setSelectionSet(
                    [
                        'name',
                        'serialNumber'
                    ]
                );


            try {
                $results = $this->gqlClient->runQuery($gql);
            }

            catch (QueryError $exception) {
                print_r($exception->getErrorDetails());
                exit;
            }

            $results = $this->gqlClient->runQuery($gql, true); // array structure
            return $results;
        }

    }

I want to get the array data for

->setVariables(
    [
        new Variable('name', 'String', true),
        new Variable('limit', 'Int', false, 5)
    ]
)
->setArguments(
    [
        'name' => '$name',
        'first' => '$limit'
    ]
)
->setSelectionSet(
    [
        'name',
        'serialNumber'
    ]
);

passed in from my Twig Templates, ideally wrapped in

{#graphql

twig tags.

1st step -- What's the right way to refactor function gqlQuery() to accept the array contents, properly encoded etc, from Twig Templates?

Template editors need to add content to the templates. Content is available via GraphQL. Twig is the template env. I need GraphQL in Twig. As in Drupal, git.drupalcode.org/project/graphql_twig but for Laravel. — user5321691
The Drupal solution is a drpal-specific solution; it's written as a Drupal module. Which works of course for Drupal. The TwigExtension approach is my attempt for something more generic/portable, and ideally simple, for the Laravel env I'm in. — user5321691

DarkBee DarkBee · Accepted Answer · 2021-03-17T13:51:37

There won't be a simple solution for this use-case if you want to handle this inside twig. You could in fact send an array to the TwigFunction, e.g.

{% set graph = glq_query({
    'variables': [
         [ 'name', 'String', true, ],
         [ 'limit', 'Int', false, 5 ],
    ],
    'arugments': {
        'name': '$name',
        'first': '$limit',
    },
    'selectionSet': [
        'name',
        'serialNumber',
    ],
}) %}

But then you would need to write validation/checks for every possible combination that could be created to control the Graph QL client

how to inject php GraphQL query results , with queries defined in Twig(Bridge) templates, using Twig Extension in Laravel8?

1 Answers