public function get_issuer() {
        $issuer = array();
        if ($this->_data) {
            // Required.
            $issuer['name'] = $this->_data->issuername;
            $issuer['url'] = $this->_data->issuerurl;
            // Optional.
            if (!empty($this->_data->issuercontact)) {
                $issuer['email'] = $this->_data->issuercontact;
            }
        }
        $this->embed_data_badge_version2($issuer, OPEN_BADGES_V2_TYPE_ISSUER);
        return $issuer;
    }