/**
* Writes the current Git commit ID to the remote site.
*
* @param \Ftp $ftp An active FTP connection.
*/
protected function writeGitCommit(\Ftp $ftp)
{
$ftp->chdir($this->targetDirectory);
// get the current commit hash
$result = (new ExecTask('git'))->arg('rev-parse')->arg('HEAD')->run();
// write the commit hash to the meta file
$stream = fopen('data://text/plain,' . trim($result->getMessage()), 'r');
$ftp->fput('.git-commit', $stream, FTP_ASCII);
}