SingleFieldSubscription.php
<?php declare(strict_types=1);
namespace Automattic\WooCommerce\Vendor\GraphQL\Validator\Rules;
use Automattic\WooCommerce\Vendor\GraphQL\Error\Error;
use Automattic\WooCommerce\Vendor\GraphQL\Language\AST\NodeKind;
use Automattic\WooCommerce\Vendor\GraphQL\Language\AST\OperationDefinitionNode;
use Automattic\WooCommerce\Vendor\GraphQL\Language\Visitor;
use Automattic\WooCommerce\Vendor\GraphQL\Language\VisitorOperation;
use Automattic\WooCommerce\Vendor\GraphQL\Validator\QueryValidationContext;
class SingleFieldSubscription extends ValidationRule
{
public function getVisitor(QueryValidationContext $context): array
{
return [
NodeKind::OPERATION_DEFINITION => static function (OperationDefinitionNode $node) use ($context): VisitorOperation {
if ($node->operation === 'subscription') {
$selections = $node->selectionSet->selections;
if (count($selections) > 1) {
$offendingSelections = $selections->splice(1, count($selections));
$context->reportError(new Error(
static::multipleFieldsInOperation($node->name->value ?? null),
$offendingSelections
));
}
}
return Visitor::skipNode();
},
];
}
public static function multipleFieldsInOperation(?string $operationName): string
{
if ($operationName === null) {
return 'Anonymous Subscription must select only one top level field.';
}
return "Subscription \"{$operationName}\" must select only one top level field.";
}
}