protected function _gatherConfigVars() {
        $source = $this->_stdin ?
            $this->_parseStdin($this->_stdin) :
            Zend_Registry::get('config')->toArray();
        $cdnConfig = f\prop('cdn', $source);
        $s3Config = f\prop('s3', $cdnConfig);
        return array(
            'apikey'          => f\prop('apikey', $s3Config),
            'secret'          => f\prop('secret', $s3Config),
            'bucket'          => f\prop('bucket', $s3Config),
            'region'          => f\prop('region', $s3Config),
            'readonly'        => f\prop('readonly', $cdnConfig),
            'gzip'            => f\prop('gzip', $cdnConfig),
            'gzip_exceptions' => f\prop('gzip_exceptions', $cdnConfig)
        );
    }