code: protected function getHttpRange($fileSize)
      {
          $rangeHeader = Yii::$app->getRequest()->getHeaders()->get('Range', '-');
          if ($rangeHeader === '-') {
              return [0, $fileSize - 1];
          }
          if (!preg_match('/^bytes=(\d*)-(\d*)$/', $rangeHeader, $matches)) {
              return false;
          }
          if ($matches[1] === '') {
              $start = $fileSize - $matches[2];
              $end = $fileSize - 1;
          } elseif ($matches[2] !== '') {
              $start = $matches[1];
              $end = $matches[2];
              if ($end >= $fileSize) {
                  $end = $fileSize - 1;
              }
          } else {
              $start = $matches[1];
              $end = $fileSize - 1;
          }
          if ($start < 0 || $start > $end) {
              return false;
          }
  
          return [$start, $end];
      }
docs: Determines the HTTP range given in the request.
  @param int $fileSize the size of the file that will be used to validate the requested HTTP range.
  @return array|bool the range (begin, end), or false if the range request is invalid.