code: private function update($documents, $repository, $commitSize)
      {
          if (count($documents) > $commitSize && $commitSize > 1) {
              $esResponse = [];
              $i = 1;
              foreach ($documents as $document) {
                  $id = $document['_id'];
                  unset($document['_id']);
                  $this->crud->update($repository, $id, $document);
                  if ($i++ % ($commitSize - 1) == 0) {
                      $esResponse[] = $this->crud->commit($repository);
                  }
              }
          } else {
              foreach ($documents as $document) {
                  $id = $document['_id'];
                  unset($document['_id']);
                  $this->crud->update($repository, $id, $document);
              }
              $esResponse = $this->crud->commit($repository);
          }
          return json_encode($esResponse);
      }
docs: Handles update action
  
  @param array      $documents
  @param Repository $repository
  @param integer    $commitSize
  
  @return string