Neos\Flow\Property\PropertyMappingConfigurationInterface::getConfigurationValue PHP Method

    public function getConfigurationValue($typeConverterClassName, $key);

 /**
  * Convert the given $source to $targetType depending on the MediaTypeConverterInterface::CONFIGURATION_MEDIA_TYPE property mapping configuration
  *
  * @param string $source the raw request body
  * @param string $targetType must be "array"
  * @param array $convertedChildProperties
  * @param PropertyMappingConfigurationInterface $configuration
  * @return array
  * @api
  */
 public function convertFrom($source, $targetType, array $convertedChildProperties = [], PropertyMappingConfigurationInterface $configuration = null)
 {
     $mediaType = null;
     if ($configuration !== null) {
         $mediaType = $configuration->getConfigurationValue(MediaTypeConverterInterface::class, MediaTypeConverterInterface::CONFIGURATION_MEDIA_TYPE);
     }
     if ($mediaType === null) {
         $mediaType = MediaTypeConverterInterface::DEFAULT_MEDIA_TYPE;
     }
     return $this->convertMediaType($source, $mediaType);
 }