SimpleSAML_Utilities::loadPublicKey PHP Method

    public static function loadPublicKey(SimpleSAML_Configuration $metadata, $required = false, $prefix = '')
    {
        return SimpleSAML\Utils\Crypto::loadPublicKey($metadata, $required, $prefix);
    }

 protected function createLogoutResponse($testrun, $logoutRequest, $logoutRelayState)
 {
     $this->log($testrun, 'Creating response with relaystate [' . $logoutRelayState . ']');
     $idpMetadata = SimpleSAML_Configuration::loadFromArray($this->idpmetadata);
     $spMetadata = SimpleSAML_Configuration::loadFromArray($this->metadata);
     // Get SingleLogoutService URL
     $consumerURLf = $spMetadata->getDefaultEndpoint('SingleLogoutService', array('urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Redirect'));
     $consumerURL = $consumerURLf['Location'];
     /* Create an send response. */
     $response = sspmod_saml2_Message::buildLogoutResponse($idpMetadata, $spMetadata);
     $response->setRelayState($logoutRequest->getRelayState());
     $response->setInResponseTo($logoutRequest->getId());
     $keyArray = SimpleSAML_Utilities::loadPrivateKey($idpMetadata, TRUE);
     $certArray = SimpleSAML_Utilities::loadPublicKey($idpMetadata, FALSE);
     $privateKey = new XMLSecurityKey(XMLSecurityKey::RSA_SHA1, array('type' => 'private'));
     $privateKey->loadKey($keyArray['PEM'], FALSE);
     $response->setSignatureKey($privateKey);
     if ($certArray === NULL) {
         throw new Exception('No certificates found. [1]');
     }
     if (!array_key_exists('PEM', $certArray)) {
         throw new Exception('No certificates found. [2]');
     }
     $response->setCertificates(array($certArray['PEM']));
     #$this->tweakResponse($testrun, $response);
     $msgStr = $response->toUnsignedXML();
     #$this->tweakResponseDOM($testrun, $msgStr);
     $msgStr = $msgStr->ownerDocument->saveXML($msgStr);
     #	echo '<pre>'; echo(htmlspecialchars($msgStr)); exit;
     #		$msgStr = base64_encode($msgStr);
     #		$msgStr = htmlspecialchars($msgStr);
     return array('url' => $consumerURL, 'Response' => $msgStr, 'ResponseObj' => $response, 'RelayState' => $logoutRelayState);
 }