Collaboration diagram for ilLTIConsumerContentGUI:

Public Member Functions
	__construct (ilObjLTIConsumer $object)

	executeCommand ()

Static Public Member Functions
static	isEmbeddedLaunchRequest ()

Data Fields
const	CMD_LAUNCH = 'launch'

const	CMD_SHOW_EMBEDDED = 'showEmbedded'

Protected Member Functions
	launch ()

	getLoginLTI13Form ()

	getStartButtonTxt11 ()

	getStartButtonTxt13 ()

	getEmbeddedAutoStartFormular ()

	showEmbedded ()

	getLaunchParameters ()

	getLaunchParametersLTI13 (string $endpoint, string $clientId, int $deploymentId, string $nonce)

	initCmixUser ()

	getRequestValue (string $key, $default=null)

Protected Attributes
ilObjLTIConsumer	$object

ilCmiXapiUser	$cmixUser

Private Member Functions
	validateLTI13InitalLogin (array $loginData)

Private Attributes
ILIAS DI Container	$dic

ilLanguage	$lng

ilObjUser	$user

Detailed Description

Definition at line 30 of file class.ilLTIConsumerContentGUI.php.

Constructor & Destructor Documentation

◆ __construct()

ilLTIConsumerContentGUI::__construct ( ilObjLTIConsumer $object )

Definition at line 45 of file class.ilLTIConsumerContentGUI.php.

References $DIC, $object, ILIAS\Repository\lng(), and ILIAS\Repository\user().

     {
         global $DIC;
         $this->dic = $DIC;
         $this->lng = $DIC->language();
         $this->user = $DIC->user();
         $this->object = $object;
     }

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Member Function Documentation

◆ executeCommand()

ilLTIConsumerContentGUI::executeCommand ( )

Exceptions

ilLtiConsumerException

Definition at line 57 of file class.ilLTIConsumerContentGUI.php.

References $DIC, ilLTIConsumeProvider\AVAILABILITY_NONE, and ILIAS\Repository\object().

                                     : void
     {
         global $DIC; /* @var \ILIAS\DI\Container $DIC */
 
         if ($this->object->getProvider()->getAvailability() == ilLTIConsumeProvider::AVAILABILITY_NONE) {
             throw new ilLtiConsumerException('access denied!');
         }
         $command = $DIC->ctrl()->getCmd(self::CMD_LAUNCH);
         $this->{$command}();
     }

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◆ getEmbeddedAutoStartFormular()

ilLTIConsumerContentGUI::getEmbeddedAutoStartFormular ( )

protected

Definition at line 268 of file class.ilLTIConsumerContentGUI.php.

References $context, $ltiMessageHint, CLIENT_ID, ilObjLTIConsumer\getIliasHttpPath(), initCmixUser(), ILIAS\Repository\object(), and ilSession\set().

Referenced by showEmbedded().

                                                      : string
     {
         $this->initCmixUser();
         $user_ident = $this->cmixUser->getUsrIdent();
         $ilLTIConsumerLaunch = new ilLTIConsumerLaunch($this->object->getRefId());
         $context = $ilLTIConsumerLaunch->getContext();
         $contextType = $ilLTIConsumerLaunch::getLTIContextType($context["type"]);
         $contextId = $context["id"];
         $contextTitle = $context["title"];
 
         $target = "_self";
         $output = '';
         $ltiMessageHint = (string) $this->object->getRefId() . ":" . CLIENT_ID;
         ilSession::set('lti_message_hint', $ltiMessageHint);
         $output = '<form id="lti_launch_form" name="lti_launch_form" action="' . $this->object->getProvider()->getInitiateLogin() . '" method="post" target="' . $target . '" encType="application/x-www-form-urlencoded">';
         $output .= sprintf('<input type="hidden" name="%s" value="%s" />', 'iss', ilObjLTIConsumer::getIliasHttpPath()) . "\n";
         $output .= sprintf('<input type="hidden" name="%s" value="%s" />', 'target_link_uri', $this->object->getProvider()->getProviderUrl()) . "\n";
         $output .= sprintf('<input type="hidden" name="%s" value="%s" />', 'login_hint', $user_ident) . "\n";
         $output .= sprintf('<input type="hidden" name="%s" value="%s" />', 'lti_message_hint', $ltiMessageHint) . "\n";
         $output .= sprintf('<input type="hidden" name="%s" value="%s" />', 'client_id', $this->object->getProvider()->getClientId()) . "\n";
         $output .= sprintf('<input type="hidden" name="%s" value="%s" />', 'lti_deployment_id', $this->object->getProvider()->getId()) . "\n";
         $output .= '</form>';
 
         $output .= "<script type=\"text/javascript\">\n" .
                 "//<![CDATA[\n" .
                 "document.lti_launch_form.submit();\n" .
                 "//]]>\n" .
                 "</script>\n";
 
         return($output);
     }

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◆ getLaunchParameters()

ilLTIConsumerContentGUI::getLaunchParameters ( )

protected

Definition at line 336 of file class.ilLTIConsumerContentGUI.php.

References $token, ilCmiXapiAuthToken\fillToken(), ilLTIConsumerLaunch\getContext(), ilLTIConsumerLaunch\getLTIContextType(), and ILIAS\Repository\object().

Referenced by showEmbedded().

                                             : array
     {
         $ilLTIConsumerLaunch = new ilLTIConsumerLaunch($this->object->getRefId());
         $launchContext = $ilLTIConsumerLaunch->getContext();
 
         $launchContextType = ilLTIConsumerLaunch::getLTIContextType($launchContext["type"]);
         $launchContextId = $launchContext["id"];
         $launchContextTitle = $launchContext["title"];
 
         $token = ilCmiXapiAuthToken::fillToken(
             $this->dic->user()->getId(),
             $this->object->getRefId(),
             $this->object->getId()
         );
 
         return $this->object->buildLaunchParameters(
             $this->cmixUser,
             $token,
             $launchContextType,
             $launchContextId,
             $launchContextTitle
         );
     }

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◆ getLaunchParametersLTI13()

ilLTIConsumerContentGUI::getLaunchParametersLTI13	(	string	$endpoint,
		string	$clientId,
		int	$deploymentId,
		string	$nonce
	)

protected

Definition at line 360 of file class.ilLTIConsumerContentGUI.php.

References $cmixUser, ilLTIConsumerLaunch\getContext(), ilObjLTIConsumer\getIliasHttpPath(), ilLTIConsumerLaunch\getLTIContextType(), and ILIAS\Repository\object().

Referenced by getLoginLTI13Form().

                                                                                                                      : ?array
     {
         $ilLTIConsumerLaunch = new ilLTIConsumerLaunch($this->object->getRefId());
         $launchContext = $ilLTIConsumerLaunch->getContext();
 
         $launchContextType = ilLTIConsumerLaunch::getLTIContextType($launchContext["type"]);
         $launchContextId = $launchContext["id"];
         $launchContextTitle = $launchContext["title"];
 
         $returnUrl = !$this->object->isLaunchMethodOwnWin() ? '' : str_replace(
             '&amp;',
             '&',
             ilObjLTIConsumer::getIliasHttpPath() . "/" . $this->dic->ctrl()->getLinkTarget($this, "", "", false)
         );
 
         $cmixUser = $this->cmixUser;
         return $this->object->buildLaunchParametersLTI13(
             $cmixUser,
             $endpoint,
             $clientId,
             $deploymentId,
             $nonce,
             $launchContextType,
             $launchContextId,
             $launchContextTitle,
             $returnUrl
         );
     }

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◆ getLoginLTI13Form()

ilLTIConsumerContentGUI::getLoginLTI13Form ( )

protected

Definition at line 118 of file class.ilLTIConsumerContentGUI.php.

References ILIAS\LTI\ToolProvider\$key, $params, $r, ilSession\clear(), ilSession\get(), getLaunchParametersLTI13(), initCmixUser(), ILIAS\Repository\object(), and validateLTI13InitalLogin().

Referenced by launch().

                                           : ?string
     {
         $loginData = ilSession::get('lti13_login_data');
         ilSession::clear('lti13_login_data');
         $err = $this->validateLTI13InitalLogin($loginData);
         if ($err !== null) {
             return null;
         } else {
             $this->initCmixUser();
             $params = $this->getLaunchParametersLTI13($loginData['redirect_uri'], $this->object->getProvider()->getClientId(), $this->object->getProvider()->getId(), $loginData['nonce']);
             if (isset($loginData['state'])) {
                 $params['state'] = $loginData['state'];
             }
             ilSession::clear('lti_message_hint');
             $r = '<form action="' . $loginData['redirect_uri'] . "\" name=\"ltiAuthForm\" id=\"ltiAuthForm\" " .
                 "method=\"post\" enctype=\"application/x-www-form-urlencoded\">\n";
             if (!empty($params)) {
                 foreach ($params as $key => $value) {
                     $key = htmlspecialchars($key);
                     $value = htmlspecialchars($value);
                     $r .= "  <input type=\"hidden\" name=\"{$key}\" value=\"{$value}\"/>\n";
                 }
             }
             $r .= "</form>\n";
             $r .= "<script type=\"text/javascript\">\n" .
                 "//<![CDATA[\n" .
                 "document.ltiAuthForm.submit();\n" .
                 "//]]>\n" .
                 "</script>\n";
             //ilObjLTIConsumer::getLogger()->dump($r);
             return $r;
         }
         return null;
     }

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◆ getRequestValue()

ilLTIConsumerContentGUI::getRequestValue	(	string	$key,
			$default = `null`
	)

protected

Parameters

string	$key
mixed	$default

Returns: mixed|null

Definition at line 521 of file class.ilLTIConsumerContentGUI.php.

References $DIC, and ILIAS\LTI\ToolProvider\$key.

     {
         global $DIC;
         if (isset($DIC->http()->request()->getQueryParams()[$key])) {
             return $DIC->http()->request()->getQueryParams()[$key];
         }
 
         if (isset($DIC->http()->request()->getParsedBody()[$key])) {
             return $DIC->http()->request()->getParsedBody()[$key];
         }
 
         return $default ?? null;
     }

◆ getStartButtonTxt11()

ilLTIConsumerContentGUI::getStartButtonTxt11 ( )

protected

Definition at line 153 of file class.ilLTIConsumerContentGUI.php.

References $context, $token, ilLTIConsumeProvider\AVAILABILITY_NONE, ilCmiXapiAuthToken\fillToken(), ilCmiXapiUser\getIdent(), ilObjLTIConsumer\getIliasHttpPath(), ilCmiXapiUser\getUsrIdent(), ILIAS\Repository\lng(), ILIAS\Repository\object(), ilCmiXapiUser\save(), ilCmiXapiUser\setUsrIdent(), and ILIAS\Repository\user().

Referenced by launch().

                                             : string
     {
         if ($this->object->getOfflineStatus() ||
             $this->object->isLaunchMethodEmbedded() ||
             $this->object->getProvider()->getAvailability() == ilLTIConsumeProvider::AVAILABILITY_NONE) {
             return "";
         }
 
         $cmixUser = new ilCmiXapiUser(
             $this->object->getId(),
             $this->user->getId(),
             $this->object->getProvider()->getPrivacyIdent()
         );
         $user_ident = $cmixUser->getUsrIdent();
         if ($user_ident == '' || $user_ident == null) {
             $user_ident = ilCmiXapiUser::getIdent($this->object->getProvider()->getPrivacyIdent(), $this->dic->user());
             $cmixUser->setUsrIdent($user_ident);
             $cmixUser->save();
         }
         $ilLTIConsumerLaunch = new ilLTIConsumerLaunch($this->object->getRefId());
         $context = $ilLTIConsumerLaunch->getContext();
         $contextType = $ilLTIConsumerLaunch::getLTIContextType($context["type"]);
         $contextId = $context["id"];
         $contextTitle = $context["title"];
 
         $token = ilCmiXapiAuthToken::fillToken(
             $this->dic->user()->getId(),
             $this->object->getRefId(),
             $this->object->getId()
         );
 
         $returnUrl = !$this->object->isLaunchMethodOwnWin() ? '' : str_replace(
             '&amp;',
             '&',
             ilObjLTIConsumer::getIliasHttpPath() . "/" . $this->dic->ctrl()->getLinkTarget($this, "", "", false)
         );
 
         $launchParameters = $this->object->buildLaunchParameters(
             $cmixUser,
             $token,
             $contextType,
             $contextId,
             $contextTitle,
             $returnUrl
         );
 
         $target = $this->object->getLaunchMethod() == "newWin" ? "_blank" : "_self";
         $button = '<input class="btn btn-default ilPre" type="button" onClick="ltilaunch()" value = "' . $this->lng->txt("show_content") . '" />';
         $output = '<form id="lti_launch_form" name="lti_launch_form" action="' . $this->object->getProvider()->getProviderUrl() . '" method="post" target="' . $target . '" encType="application/x-www-form-urlencoded">';
         foreach ($launchParameters as $field => $value) {
             $output .= sprintf('<input type="hidden" name="%s" value="%s" />', $field, $value) . "\n";
         }
         $output .= $button;
         $output .= '</form>';
         $output .= '<span id ="lti_launched" style="display:none">' . $this->lng->txt("launched") . '</span>';
         $output .= '<script type="text/javascript">
         function ltilaunch() {
             document.lti_launch_form.submit();
             document.getElementById("lti_launch_form").style.display = "none";
             document.getElementById("lti_launched").style.display = "inline";
         }</script>';
         return($output);
     }

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◆ getStartButtonTxt13()

ilLTIConsumerContentGUI::getStartButtonTxt13 ( )

protected

Definition at line 217 of file class.ilLTIConsumerContentGUI.php.

References $context, $ltiMessageHint, $token, ilLTIConsumeProvider\AVAILABILITY_NONE, CLIENT_ID, ilCmiXapiAuthToken\fillToken(), ilObjLTIConsumer\getIliasHttpPath(), initCmixUser(), ILIAS\Repository\lng(), ILIAS\Repository\object(), and ilSession\set().

Referenced by launch().

                                             : string
     {
         if ($this->object->getOfflineStatus() ||
             $this->object->isLaunchMethodEmbedded() ||
             $this->object->getProvider()->getAvailability() == ilLTIConsumeProvider::AVAILABILITY_NONE) {
             return "";
         }
         $this->initCmixUser();
         $user_ident = $this->cmixUser->getUsrIdent();
         $ilLTIConsumerLaunch = new ilLTIConsumerLaunch($this->object->getRefId());
         $context = $ilLTIConsumerLaunch->getContext();
         $contextType = $ilLTIConsumerLaunch::getLTIContextType($context["type"]);
         $contextId = $context["id"];
         $contextTitle = $context["title"];
 
         $token = ilCmiXapiAuthToken::fillToken(
             $this->dic->user()->getId(),
             $this->object->getRefId(),
             $this->object->getId()
         );
 
         $returnUrl = !$this->object->isLaunchMethodOwnWin() ? '' : str_replace(
             '&amp;',
             '&',
             ilObjLTIConsumer::getIliasHttpPath() . "/" . $this->dic->ctrl()->getLinkTarget($this, "", "", false)
         );
 
         $target = $this->object->getLaunchMethod() == "newWin" ? "_blank" : "_self";
         $button = '<input class="btn btn-default ilPre" type="button" onClick="ltilaunch()" value = "' . $this->lng->txt("show_content") . '" />';
         $ltiMessageHint = (string) $this->object->getRefId() . ":" . CLIENT_ID;
         ilSession::set('lti_message_hint', $ltiMessageHint);
         $output = '<form id="lti_launch_form" name="lti_launch_form" action="' . $this->object->getProvider()->getInitiateLogin() . '" method="post" target="' . $target . '" encType="application/x-www-form-urlencoded">';
         $output .= sprintf('<input type="hidden" name="%s" value="%s" />', 'iss', ilObjLTIConsumer::getIliasHttpPath()) . "\n";
         $output .= sprintf('<input type="hidden" name="%s" value="%s" />', 'target_link_uri', $this->object->getProvider()->getProviderUrl()) . "\n";
         $output .= sprintf('<input type="hidden" name="%s" value="%s" />', 'login_hint', $user_ident) . "\n";
         $output .= sprintf('<input type="hidden" name="%s" value="%s" />', 'lti_message_hint', $ltiMessageHint) . "\n";
         $output .= sprintf('<input type="hidden" name="%s" value="%s" />', 'client_id', $this->object->getProvider()->getClientId()) . "\n";
         $output .= sprintf('<input type="hidden" name="%s" value="%s" />', 'lti_deployment_id', $this->object->getProvider()->getId()) . "\n";
         $output .= $button;
         $output .= '</form>';
         $output .= '<span id ="lti_launched" style="display:none">' . $this->lng->txt("launched") . '</span>';
         $output .= '<script type="text/javascript">
         function ltilaunch() {
             document.lti_launch_form.submit();
             document.getElementById("lti_launch_form").style.display = "none";
             document.getElementById("lti_launched").style.display = "inline";
         }</script>';
         return($output);
     }

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◆ initCmixUser()

ilLTIConsumerContentGUI::initCmixUser ( )

protected

Definition at line 404 of file class.ilLTIConsumerContentGUI.php.

References ilCmiXapiUser\getIdent(), ilCmiXapiUser\getUsrIdent(), and ILIAS\Repository\object().

Referenced by getEmbeddedAutoStartFormular(), getLoginLTI13Form(), getStartButtonTxt13(), and showEmbedded().

                                      : void
     {
         $this->cmixUser = new ilCmiXapiUser($this->object->getId(), $this->dic->user()->getId(), $this->object->getProvider()->getPrivacyIdent());
         $user_ident = $this->cmixUser->getUsrIdent();
         if ($user_ident == '' || $user_ident == null) {
             $user_ident = ilCmiXapiUser::getIdent($this->object->getProvider()->getPrivacyIdent(), $this->dic->user());
             $this->cmixUser->setUsrIdent($user_ident);
             $this->cmixUser->save();
         }
     }

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◆ isEmbeddedLaunchRequest()

static ilLTIConsumerContentGUI::isEmbeddedLaunchRequest ( )

static

Definition at line 389 of file class.ilLTIConsumerContentGUI.php.

References $DIC.

Referenced by ilObjLTIConsumerGUI\_goto().

                                                     : bool
     {
         global $DIC; /* @var \ILIAS\DI\Container $DIC */
 
         if ($DIC->ctrl()->getNextClass() != strtolower(self::class)) {
             return false;
         }
 
         if ($DIC->ctrl()->getCmd() != self::CMD_SHOW_EMBEDDED) {
             return false;
         }
 
         return true;
     }

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◆ launch()

ilLTIConsumerContentGUI::launch ( )

protected

Exceptions

ilCtrlException
ilTemplateException

Definition at line 72 of file class.ilLTIConsumerContentGUI.php.

References $response, ilSession\get(), getLoginLTI13Form(), getStartButtonTxt11(), getStartButtonTxt13(), and ILIAS\Repository\object().

                                : void
     {
         if ($this->dic->access()->checkAccess('read', '', $this->object->getRefId())) {
             if ($this->object->getProvider()->getLtiVersion() == "LTI-1p0") {
                 if ($this->object->isLaunchMethodEmbedded()) {
                     $tpl = new ilTemplate('tpl.lti_content.html', true, true, 'Modules/LTIConsumer');
                     $tpl->setVariable("EMBEDDED_IFRAME_SRC", $this->dic->ctrl()->getLinkTarget(
                         $this,
                         self::CMD_SHOW_EMBEDDED
                     ));
                     $this->dic->ui()->mainTemplate()->setContent($tpl->get());
                 } else {
                     $this->dic->toolbar()->addText($this->getStartButtonTxt11());
                 }
             } else {
                 if ($this->object->isLaunchMethodEmbedded() && (ilSession::get('lti13_login_data') == null)) {
                     $tpl = new ilTemplate('tpl.lti_content.html', true, true, 'Modules/LTIConsumer');
                     $tpl->setVariable("EMBEDDED_IFRAME_SRC", $this->dic->ctrl()->getLinkTarget(
                         $this,
                         self::CMD_SHOW_EMBEDDED
                     ));
                     $this->dic->ui()->mainTemplate()->setContent($tpl->get());
                 } else {
                     if (ilSession::get('lti13_login_data') != null) {
                         $form = $this->getLoginLTI13Form();
                         if ($form == null) {
                             //                        $this->dic->ui()->mainTemplate()->setOnScreenMessage('failure', 'initialLogin Error: ' . $err, true);
                             $this->dic->ui()->mainTemplate()->setOnScreenMessage(
                                 'failure',
                                 'initialLogin Error: ',
                                 true
                             );
                         } else {
                             $response = $this->dic->http()->response()->withBody(ILIAS\Filesystem\Stream\Streams::ofString($form));
                             $this->dic->http()->saveResponse($response);
                             $this->dic->http()->sendResponse();
                             $this->dic->http()->close();
                         }
                     } else {
                         $this->dic->toolbar()->addText($this->getStartButtonTxt13());
                     }
                 }
             }
         }
     }

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◆ showEmbedded()

ilLTIConsumerContentGUI::showEmbedded ( )

protected

Exceptions

ilTemplateException

Definition at line 304 of file class.ilLTIConsumerContentGUI.php.

References $response, exit, getEmbeddedAutoStartFormular(), ilUtil\getImagePath(), getLaunchParameters(), ILIAS_VERSION_NUMERIC, initCmixUser(), and ILIAS\Repository\object().

                                      : void
     {
         if ($this->object->getProvider()->getLtiVersion() == "LTI-1p0") {
             $this->initCmixUser();
             $tpl = new ilTemplate('tpl.lti_embedded.html', true, true, 'Modules/LTIConsumer');
             foreach ($this->getLaunchParameters() as $field => $value) {
                 $tpl->setCurrentBlock('launch_parameter');
                 $tpl->setVariable('LAUNCH_PARAMETER', $field);
                 $tpl->setVariable('LAUNCH_PARAM_VALUE', $value);
                 $tpl->parseCurrentBlock();
             }
 
             $v = DEVMODE ? '?vers=' . time() : '?vers=' . ILIAS_VERSION_NUMERIC;
             $tpl->setVariable("DELOS_CSS_HREF", 'templates/default/delos.css' . $v);
             $tpl->setVariable("JQUERY_SRC", 'node_modules/jquery/dist/jquery.js' . $v);
 
             $tpl->setVariable("LOADER_ICON_SRC", ilUtil::getImagePath("media/loader.svg"));
             $tpl->setVariable('LAUNCH_URL', $this->object->getProvider()->getProviderUrl());
 
             #$DIC->ui()->mainTemplate()->getStandardTemplate();
             #$DIC->ui()->mainTemplate()->setContent($tpl->get());
 
             echo $tpl->get();
             exit; //TODO: no exit
         } else {
             $response = $this->dic->http()->response()->withBody(ILIAS\Filesystem\Stream\Streams::ofString($this->getEmbeddedAutoStartFormular()));
             $this->dic->http()->saveResponse($response);
             $this->dic->http()->sendResponse();
             $this->dic->http()->close();
         }
     }

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◆ validateLTI13InitalLogin()

ilLTIConsumerContentGUI::validateLTI13InitalLogin ( array $loginData )

private

Definition at line 415 of file class.ilLTIConsumerContentGUI.php.

References $ref_id, $scope, ilSession\get(), ilObjLTIConsumer\getLogger(), ilCmiXapiUser\getUsrIdent(), ILIAS\Repository\int(), ILIAS\Repository\object(), and ILIAS\Repository\user().

Referenced by getLoginLTI13Form().

                                                                : ?string
     {
         $scope = $loginData['scope'];
         $responsetype = $loginData['response_type'];
         $clientid = $loginData['client_id'];
         $redirecturi = $loginData['redirect_uri'];
         $loginhint = $loginData['login_hint'];
         $ltimessagehint = $loginData['lti_message_hint'];
         $state = $loginData['state'];
         $responsemode = $loginData['response_mode'];
         $nonce = $loginData['nonce'];
         $prompt = $loginData['prompt'];
 
         $desc = '';
 
         $ok = !empty($scope) && !empty($responsetype) && !empty($clientid) &&
             !empty($redirecturi) && !empty($loginhint) &&
             !empty($nonce) && (ilSession::get('lti_message_hint') != null);
 
         if (!$ok) {
             $error = 'invalid_request';
         }
         if ($ok && ($scope !== 'openid')) {
             $ok = false;
             $error = 'invalid_scope';
         }
         if ($ok && ($responsetype !== 'id_token')) {
             $ok = false;
             $error = 'unsupported_response_type';
         }
         if ($ok) {
             list($ref_id, $ilias_client_id) = explode(':', ilSession::get('lti_message_hint'), 2);
             if ((int) $this->object->getRefId() !== (int) $ref_id) {
                 $ok = false;
                 $error = 'invalid_request';
             }
             if ($this->object->getProvider()->getClientId() !== $clientid) {
                 $ok = false;
                 $error = 'unauthorized_client';
             }
         }
 
         if ($ok) {
             $cmixUser = new ilCmiXapiUser(
                 $this->object->getId(),
                 $this->user->getId(),
                 $this->object->getProvider()->getPrivacyIdent()
             );
             $user_ident = $cmixUser->getUsrIdent();
             // required?
             //            if ($user_ident == '' || $user_ident == null) {
             //                $user_ident = ilCmiXapiUser::getIdent($this->object->getProvider()->getPrivacyIdent(), $this->dic->user());
             //                $cmixUser->setUsrIdent($user_ident);
             //                $cmixUser->save();
             //            }
 
             if ((string) $loginhint !== $user_ident) {
                 $ok = false;
                 $error = 'access_denied';
             }
         }
         $uris = array_map("trim", explode(",", $this->object->getProvider()->getRedirectionUris()));
         if (!in_array($redirecturi, $uris)) {
             $ok = false;
             $error = 'invalid_request';
         }
 
         if ($ok) {
             if (isset($responsemode)) {
                 $ok = ($responsemode === 'form_post');
                 if (!$ok) {
                     $error = 'invalid_request';
                     $desc = 'Invalid response_mode';
                 }
             } else {
                 $ok = false;
                 $error = 'invalid_request';
                 $desc = 'Missing response_mode';
             }
         }
         if ($ok && !empty($prompt) && ($prompt !== 'none')) {
             $ok = false;
             $error = 'invalid_request';
             $desc = 'Invalid prompt';
         }
         if ($ok) {
             ilObjLTIConsumer::getLogger()->debug("no error");
             return null;
         } else {
             $err = "error '" . $error . "'";
             if ($desc != '') {
                 $err .= " with description: " . $desc;
             }
             ilObjLTIConsumer::getLogger()->error($err);
             ilObjLTIConsumer::getLogger()->dump($loginData);
             return $error;
         }
     }