src/Executor/ReferenceExecutor.php
private function getOperationRootType(Schema $schema, OperationDefinitionNode $operation)
    {
        switch ($operation->operation) {
            case 'query':
                $queryType = $schema->getQueryType();
                if (! $queryType) {
                    throw new Error(
                        'Schema does not define the required query root type.',
                        [$operation]
                    );
                }

                return $queryType;
            case 'mutation':
                $mutationType = $schema->getMutationType();
                if (! $mutationType) {
                    throw new Error(
                        'Schema is not configured for mutations.',
                        [$operation]
                    );
                }

                return $mutationType;
            case 'subscription':
                $subscriptionType = $schema->getSubscriptionType();
                if (! $subscriptionType) {
                    throw new Error(
                        'Schema is not configured for subscriptions.',
                        [$operation]
                    );
                }

                return $subscriptionType;
            default:
                throw new Error(
                    'Can only execute queries, mutations and subscriptions.',
                    [$operation]
                );
        }
    }
private function getOperationRootType(Schema $schema, OperationDefinitionNode $operation)
    {
        switch ($operation->operation) {
            case 'query':
                $queryType = $schema->getQueryType();
                if (! $queryType) {
                    throw new Error(
                        'Schema does not define the required query root type.',
                        [$operation]
                    );
                }

                return $queryType;
            case 'mutation':
                $mutationType = $schema->getMutationType();
                if (! $mutationType) {
                    throw new Error(
                        'Schema is not configured for mutations.',
                        [$operation]
                    );
                }

                return $mutationType;
            case 'subscription':
                $subscriptionType = $schema->getSubscriptionType();
                if (! $subscriptionType) {
                    throw new Error(
                        'Schema is not configured for subscriptions.',
                        [$operation]
                    );
                }

                return $subscriptionType;
            default:
                throw new Error(
                    'Can only execute queries, mutations and subscriptions.',
                    [$operation]
                );
        }
    }
private function getOperationRootType ( Schema $ schema , OperationDefinitionNode $ operation ) { switch ( $ operation -> operation ) { case 'query' : $ queryType = $ schema -> getQueryType ( ) ; if ( ! $ queryType ) { throw new Error ( 'Schema does not define the required query root type.' , [ $ operation ] ) ; } return $ queryType ; case 'mutation' : $ mutationType = $ schema -> getMutationType ( ) ; if ( ! $ mutationType ) { throw new Error ( 'Schema is not configured for mutations.' , [ $ operation ] ) ; } return $ mutationType ; case 'subscription' : $ subscriptionType = $ schema -> getSubscriptionType ( ) ; if ( ! $ subscriptionType ) { throw new Error ( 'Schema is not configured for subscriptions.' , [ $ operation ] ) ; } return $ subscriptionType ; default : throw new Error ( 'Can only execute queries, mutations and subscriptions.' , [ $ operation ] ) ; } }
Extracts the root type of the operation from the schema.

@return ObjectType

@throws Error
Extracts the root type of the operation from the schema .