code: public function findByNodeIdAndSiteIdWithBlocksInArea($nodeId, $siteId, $areaId)
      {
          $qa = $this->createAggregationQueryBuilderWithSiteId($siteId);
          $qa->match(array(
                  'nodeId' => $nodeId,
                  'areas.'.$areaId.'.blocks.0' => array('$exists' => true),
          ));
  
          return $this->findLastVersionInLanguage($qa);
      }
docs: @param string $nodeId
  @param string $siteId
  @param string $areaId
  
  @return array