code: private function readPackageReleases($baseUrl, $packageName)
      {
          $result = array();
  
          try {
              $xmlPath = '/r/' . strtolower($packageName) . '/allreleases.xml';
              $xml = $this->requestXml($baseUrl, $xmlPath);
              $xml->registerXPathNamespace('ns', self::ALL_RELEASES_NS);
              foreach ($xml->xpath('ns:r') as $node) {
                  $releaseVersion = (string) $node->v;
                  $releaseStability = (string) $node->s;
  
                  try {
                      $result[$releaseVersion] = new ReleaseInfo(
                          $releaseStability,
                          $this->readPackageReleaseDependencies($baseUrl, $packageName, $releaseVersion)
                      );
                  } catch (TransportException $exception) {
                      if ($exception->getCode() != 404) {
                          throw $exception;
                      }
                  }
              }
          } catch (TransportException $exception) {
              if ($exception->getCode() != 404) {
                  throw $exception;
              }
          }
  
          return $result;
      }
docs: Read package releases from
  {baseUrl}/p/{package}/allreleases.xml
  
  @param string $baseUrl
  @param string $packageName
  @throws \Composer\Downloader\TransportException|\Exception
  @return ReleaseInfo[]                                      hash array with keys as version numbers