Neomerx\JsonApi\Encoder\Parser\ParserManager::getFieldSet PHP Метод

    public function getFieldSet($type)
    {
        settype($type, 'string');
        if (array_key_exists($type, $this->fieldSetCache) === false) {
            $fieldSet = $this->parameterAnalyzer->getParameters()->getFieldSet($type);
            $this->fieldSetCache[$type] = $fieldSet === null ? null : array_flip(array_values($fieldSet));
        }
        return $this->fieldSetCache[$type];
    }