Pantheon\Terminus\Commands\Backup\RestoreCommand::restoreBackup PHP Method

    public function restoreBackup($site_env, array $options = ['file' => null, 'element' => null])
    {
        list($site, $env) = $this->getSiteEnv($site_env);
        if (isset($options['file']) && !is_null($file_name = $options['file'])) {
            $backup = $env->getBackups()->getBackupByFileName($file_name);
        } else {
            $element = $options['element'] == 'db' ? 'database' : $options['element'];
            $backups = $env->getBackups()->getFinishedBackups($element);
            if (empty($backups)) {
                throw new TerminusNotFoundException('No backups available. Create one with `terminus backup:create {site}.{env}`', ['site' => $site->get('name'), 'env' => $env->id]);
            }
            $backup = array_shift($backups);
        }
        $workflow = $backup->restore();
        $workflow->wait();
        if ($workflow->isSuccessful()) {
            $this->log()->notice('Restored the backup to {env}.', ['env' => $env->id]);
        } else {
            $message = $workflow->getMessage();
            if (trim($message) == 'Successfully queued restore_site') {
                $message = 'There was an error while restoring your backup.';
            }
            throw new TerminusException($message);
        }
    }