Elastica\Type\Mapping::getProperties PHP Method

    public function getProperties()
    {
        return $this->getParam('properties');
    }

 /**
  * Add a mapping for the location of the photograph
  */
 public function updateElasticsearchMapping(\Elastica\Type\Mapping $mapping)
 {
     // get the properties of the individual fields as an array
     $properties = $mapping->getProperties();
     // enable tags to be faceted
     $properties['RawValue'] = array('type' => 'string', 'index' => 'not_analyzed');
     // set the new properties on the mapping
     $mapping->setProperties($properties);
     return $mapping;
 }