code: private function resolveContextValue(
          ServerConfig $config,
          OperationParams $params,
          DocumentNode $doc,
          $operationType
      ) {
          $context = $config->getContext();
  
          if (is_callable($context)) {
              $context = $context($params, $doc, $operationType);
          }
  
          return $context;
      }
docs: @param string $operationType
  
  @return mixed