Acquia\Cloud\Api\CloudApiClient::restoreDatabaseBackup PHP Method

    public function restoreDatabaseBackup($site, $env, $db, $backupId)
    {
        $variables = array('site' => $site, 'env' => $env, 'db' => $db, 'id' => $backupId);
        $request = $this->post(array('{+base_path}/sites/{site}/envs/{env}/dbs/{db}/backups/{id}/restore.json', $variables));
        return new Response\Task($request);
    }