current code from svn, revision 62608

1 files changed, 574 insertions, 0 deletions

diff --git a/app/controllers/course/lti.php b/app/controllers/course/lti.php
new file mode 100644
index 0000000..921a760
--- /dev/null
+++ b/app/controllers/course/lti.php
@@ -0,0 +1,574 @@
+<?php
+/**
+ * course/lti.php - LTI consumer API for Stud.IP
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * @author      Elmar Ludwig
+ * @license     http://www.gnu.org/licenses/gpl-2.0.html GPL version 2
+ */
+
+class Course_LtiController extends StudipController
+{
+    /**
+     * Callback function being called before an action is executed.
+     */
+    public function before_filter(&$action, &$args)
+    {
+        // these actions do not require session authentication
+        if (in_array($action, ['profile', 'outcome'])) {
+            return parent::before_filter($action, $args);
+        }
+
+        $this->with_session = true;
+        $this->allow_nobody = false;
+
+        parent::before_filter($action, $args);
+
+        $this->course_id = Context::getId();
+        $this->edit_perm = $GLOBALS['perm']->have_studip_perm('tutor', $this->course_id);
+
+        if (!in_array($action, ['index', 'iframe', 'grades']) && !$this->edit_perm) {
+            throw new AccessDeniedException(_('Sie besitzen keine Berechtigung, um LTI-Tools zu konfigurieren.'));
+        }
+
+        if ($action !== 'grades') {
+            Navigation::activateItem('/course/lti/index');
+        }
+
+        $title = CourseConfig::get($this->course_id)->LTI_TOOL_TITLE;
+        PageLayout::setTitle(Context::getHeaderLine() . ' - ' . $title);
+    }
+
+    /**
+     * Display the list of LTI content blocks.
+     */
+    public function index_action()
+    {
+        $this->lti_data_array = LtiData::findByCourse_id($this->course_id, 'ORDER BY position');
+
+        if ($this->edit_perm) {
+            $widget = Sidebar::get()->addWidget(new ActionsWidget());
+            $widget->addLink(
+                _('Einstellungen'),
+                $this->url_for('course/lti/config'),
+                Icon::create('admin')
+            )->asDialog('size=auto');
+            $widget->addLink(
+                _('Abschnitt hinzufügen'),
+                $this->url_for('course/lti/edit'),
+                Icon::create('add')
+            )->asDialog();
+
+            if (LtiTool::findByDeep_linking(1)) {
+                $widget->addLink(
+                    _('Link aus LTI-Tool einfügen'),
+                    $this->url_for('course/lti/add_link'),
+                    Icon::create('add')
+                )->asDialog('size=auto');
+            }
+        }
+
+        Helpbar::get()->addPlainText('', _('Auf dieser Seite können Sie externe Anwendungen einbinden, sofern diese den LTI-Standard (Version 1.x) unterstützen.'));
+    }
+
+    /**
+     * Display the launch form for a tool as an iframe.
+     */
+    public function iframe_action()
+    {
+        $this->launch_url  = Request::get('launch_url');
+        $this->launch_data = Request::getArray('launch_data');
+        $this->signature   = Request::get('signature');
+
+        $this->set_layout(null);
+    }
+
+    /**
+     * Edit the course settings.
+     */
+    public function config_action()
+    {
+        $this->title = CourseConfig::get($this->course_id)->LTI_TOOL_TITLE;
+    }
+
+    /**
+     * Save the course settings.
+     */
+    public function save_config_action()
+    {
+        CSRFProtection::verifyUnsafeRequest();
+
+        $title = trim(Request::get('title'));
+        CourseConfig::get($this->course_id)->store('LTI_TOOL_TITLE', $title);
+
+        PageLayout::postSuccess(_('Die Einstellungen wurden gespeichert.'));
+        $this->redirect('course/lti');
+    }
+
+    /**
+     * Move an LTI content block (either up or down).
+     *
+     * @param   int $position   block position
+     * @param   string $direction 'up' or 'down'
+     */
+    public function move_action($position, $direction)
+    {
+        CSRFProtection::verifyUnsafeRequest();
+
+        if ($direction === 'up') {
+            $position2 = $position - 1;
+        } else {
+            $position2 = $position + 1;
+        }
+
+        $lti_data = LtiData::findByCourseAndPosition($this->course_id, $position);
+        $lti_data2 = LtiData::findByCourseAndPosition($this->course_id, $position2);
+
+        if ($lti_data && $lti_data2) {
+            $lti_data->position = $position2;
+            $lti_data->store();
+
+            $lti_data2->position = $position;
+            $lti_data2->store();
+        }
+
+        $this->redirect('course/lti');
+    }
+
+    /**
+     * Edit an LTI content block (using a dialog window).
+     *
+     * @param   int $position   block position (blank: create a new block)
+     */
+    public function edit_action($position = '')
+    {
+        if ($position !== '') {
+            $this->lti_data = LtiData::findByCourseAndPosition($this->course_id, $position);
+        }
+
+        $this->tools = LtiTool::findAll();
+    }
+
+    /**
+     * Save an LTI content block.
+     *
+     * @param   int $position   block position (blank: create a new block)
+     */
+    public function save_action($position)
+    {
+        CSRFProtection::verifyUnsafeRequest();
+
+        if ($position !== '') {
+            $lti_data = LtiData::findByCourseAndPosition($this->course_id, $position);
+        } else {
+            $lti_data = new LtiData();
+            $lti_data->course_id = $this->course_id;
+            $lti_data->position = LtiData::countBySQL('course_id = ?', [$this->course_id]);
+        }
+
+        $lti_data->title = trim(Request::get('title'));
+        $lti_data->description = Studip\Markup::purifyHtml(Request::get('description'));
+        $lti_data->tool_id = Request::int('tool_id');
+
+        if ($lti_data->tool_id == 0) {
+            $lti_data->launch_url = trim(Request::get('launch_url'));
+            $options['consumer_key'] = trim(Request::get('consumer_key'));
+            $options['consumer_secret'] = trim(Request::get('consumer_secret'));
+            $options['send_lis_person'] = Request::int('send_lis_person', 0);
+            $options['oauth_signature_method'] = Request::get('oauth_signature_method', 'sha1');
+        } else {
+            $lti_data->launch_url = trim(Request::get('custom_url'));
+        }
+
+        $options['custom_parameters'] = trim(Request::get('custom_parameters'));
+        $options['document_target'] = Request::option('document_target', 'window');
+        $lti_data->options = $options;
+        $lti_data->store();
+
+        PageLayout::postSuccess(_('Der Abschnitt wurde gespeichert.'));
+        $this->redirect('course/lti');
+    }
+
+    /**
+     * Delete an LTI content block.
+     *
+     * @param   int $position   block position
+     */
+    public function delete_action($position)
+    {
+        CSRFProtection::verifyUnsafeRequest();
+
+        $lti_data = LtiData::findByCourseAndPosition($this->course_id, $position);
+        $lti_data->delete();
+
+        PageLayout::postSuccess(_('Der Abschnitt wurde gelöscht.'));
+        $this->redirect('course/lti');
+    }
+
+    /**
+     * Select a tool for adding a block via ContentItemSelectionRequest.
+     */
+    public function add_link_action()
+    {
+        $this->tools = LtiTool::findByDeep_linking(1);
+    }
+
+    /**
+     * Dispatch a ContentItemSelectionRequest to a specified LTI tool.
+     */
+    public function select_link_action()
+    {
+        $tool_id = Request::int('tool_id');
+        $tool = LtiTool::find($tool_id);
+
+        $custom_parameters = explode("\n", $tool->custom_parameters);
+        $content_item_return_url = $this->url_for('course/lti/save_link/' . $tool_id);
+
+        // set up ContentItemSelectionRequest
+        $lti_link = new LtiLink($tool->launch_url, $tool->consumer_key, $tool->consumer_secret, $tool->oauth_signature_method);
+        $lti_link->setUser($GLOBALS['user']->id, 'Instructor', $tool->send_lis_person);
+        $lti_link->setCourse($this->course_id);
+        $lti_link->addLaunchParameters([
+            'lti_message_type' => 'ContentItemSelectionRequest',
+            'accept_media_types' => 'application/vnd.ims.lti.v1.ltilink',
+            'accept_presentation_document_targets' => 'iframe,window',
+            'content_item_return_url' => $content_item_return_url,
+            'launch_presentation_locale' => str_replace('_', '-', $_SESSION['_language']),
+            'launch_presentation_document_target' => 'window'
+        ]);
+
+        foreach ($custom_parameters as $param) {
+            list($key, $value) = explode('=', $param);
+            if (isset($value)) {
+                $lti_link->addCustomParameter(trim($key), trim($value));
+            }
+        }
+
+        $this->launch_url = $lti_link->getLaunchURL();
+        $this->launch_data = $lti_link->getBasicLaunchData();
+        $this->signature = $lti_link->getLaunchSignature($this->launch_data);
+
+        $this->set_layout(null);
+        $this->render_action('iframe');
+    }
+
+    /**
+     * Create a new LTI content block for the specified tool id.
+     *
+     * @param   int $tool_id    tool id
+     */
+    public function save_link_action($tool_id)
+    {
+        require_once 'vendor/oauth-php/library/OAuthRequestVerifier.php';
+
+        $tool = LtiTool::find($tool_id);
+        $lti_msg = Request::get('lti_msg');
+        $lti_errormsg = Request::get('lti_errormsg');
+        $content_items = Request::get('content_items');
+        $content_items = json_decode($content_items, true);
+
+        OAuthStore::instance('PDO', [
+            'dsn' => 'mysql:host=' . $GLOBALS['DB_STUDIP_HOST'] . ';dbname=' . $GLOBALS['DB_STUDIP_DATABASE'],
+            'username' => $GLOBALS['DB_STUDIP_USER'],
+            'password' => $GLOBALS['DB_STUDIP_PASSWORD']
+        ]);
+
+        $oarv = new OAuthRequestVerifier();
+        $oarv->verifySignature($tool->consumer_secret, false, false);
+
+        if (is_array($content_items) && count($content_items['@graph'])) {
+            // we only support selecting a single content item
+            $item = $content_items['@graph'][0];
+
+            $lti_data = new LtiData();
+            $lti_data->course_id = $this->course_id;
+            $lti_data->position = LtiData::countBySQL('course_id = ?', [$this->course_id]);
+            $lti_data->title = (string) $item['title'];
+            $lti_data->description = Studip\Markup::purifyHtml(Studip\Markup::markAsHtml($item['text']));
+            $lti_data->tool_id = $tool_id;
+            $lti_data->launch_url = (string) $item['url'];
+
+            if (is_array($item['custom'])) {
+                foreach ($item['custom'] as $key => $value) {
+                    $custom_parameters .= $key . '=' . $value . "\n";
+                }
+
+                $options['custom_parameters'] = $custom_parameters;
+            }
+
+            if (isset($item['placementAdvice']['presentationDocumentTarget'])) {
+                $options['document_target'] = $item['placementAdvice']['presentationDocumentTarget'];
+            }
+
+            $lti_data->options = $options;
+            $lti_data->store();
+
+            PageLayout::postSuccess($lti_msg ?: _('Der Link wurde als neuer Abschnitt hinzugefügt.'));
+        }
+
+        if ($lti_errormsg) {
+            PageLayout::postError($lti_errormsg);
+        }
+
+        $this->redirect('course/lti');
+    }
+
+    /**
+     * Return an LtiLink object for the configured LTI content block.
+     *
+     * @param   LtiData $lti_data data of LTI content block
+     *
+     * @return  LtiLink  LTI link representation
+     */
+    public function getLtiLink($lti_data)
+    {
+        $launch_url = $lti_data->getLaunchURL();
+        $consumer_key = $lti_data->getConsumerKey();
+        $consumer_secret = $lti_data->getConsumerSecret();
+        $oauth_signature_method = $lti_data->getOauthSignatureMethod();
+
+        $roles = $this->edit_perm ? 'Instructor' : 'Learner';
+        $custom_parameters = explode("\n", $lti_data->getCustomParameters());
+        $description = kill_format($lti_data->description);
+        $lis_outcome_service_url = $this->url_for('course/lti/outcome/' . $lti_data->id, ['cid' => null]);
+        $tc_profile_url = $this->url_for('course/lti/profile/' . $lti_data->id, ['cid' => null]);
+
+        // set up launch request
+        $lti_link = new LtiLink($launch_url, $consumer_key, $consumer_secret, $oauth_signature_method);
+        $lti_link->setResource($lti_data->id, $lti_data->title, $description);
+        $lti_link->setUser($GLOBALS['user']->id, $roles, $lti_data->getSendLisPerson());
+        $lti_link->setCourse($lti_data->course_id);
+        $lti_link->addVariable('ToolConsumerProfile.url', $tc_profile_url);
+        $lti_link->addLaunchParameters([
+            'launch_presentation_locale' => str_replace('_', '-', $_SESSION['_language']),
+            'launch_presentation_document_target' => $lti_data->options['document_target'],
+            'lis_outcome_service_url' => $lis_outcome_service_url,
+            'lis_result_sourcedid' => $GLOBALS['user']->id
+        ]);
+
+        foreach ($custom_parameters as $param) {
+            list($key, $value) = explode('=', $param);
+            if (isset($value)) {
+                $lti_link->addCustomParameter(trim($key), trim($value));
+            }
+        }
+
+        return $lti_link;
+    }
+
+    /**
+     * Return the LTI consumer profile in standard JSON format.
+     *
+     * @param   int $id    link id
+     */
+    public function profile_action($id)
+    {
+        $profile = [
+            '@context' => ['http://purl.imsglobal.org/ctx/lti/v2/ToolConsumerProfile'],
+            '@type' => 'ToolConsumerProfile',
+            'lti_version' => 'LTI-1p0',
+            'guid' => md5(Config::get()->STUDIP_INSTALLATION_ID),
+            'product_instance' => [
+                'guid' => Config::get()->STUDIP_INSTALLATION_ID,
+                'product_info' => [
+                    'product_name' => ['default_value' => 'Stud.IP'],
+                    'product_version' => $GLOBALS['SOFTWARE_VERSION'],
+                    'product_family' => [
+                        'code' => 'studip',
+                        'vendor' => [
+                            'code' => 'studip.de',
+                            'vendor_name' => ['default_value' => 'Stud.IP e.V.'],
+                            'website' => 'https://www.studip.de/',
+                            'timestamp' => date(c)
+                        ]
+                    ]
+                ],
+                'service_owner' => [
+                    'service_owner_name' => ['default_value' => Config::get()->UNI_NAME_CLEAN],
+                    'description' => ['default_value' => $GLOBALS['UNI_INFO']],
+                    'support' => ['email' => $GLOBALS['UNI_CONTACT']],
+                    'timestamp' => date(c)
+                ]
+            ],
+            'capability_offered' => [
+                'basic-lti-launch-request',
+                'ContentItemSelectionRequest',
+                'Context.id',
+                'Context.label',
+                'Context.title',
+                'Context.type',
+                'CourseSection.courseNumber',
+                'CourseSection.credits',
+                'CourseSection.dept',
+                'CourseSection.label',
+                'CourseSection.longDescription',
+                'CourseSection.maxNumberofStudents',
+                'CourseSection.numberofStudents',
+                'CourseSection.shortDescription',
+                'CourseSection.sourcedId',
+                'CourseSection.title',
+                'Person.email.primary',
+                'Person.name.family',
+                'Person.name.full',
+                'Person.name.given',
+                'Person.name.prefix',
+                'Person.name.suffix',
+                'Person.sourcedId',
+                'Person.webaddress',
+                'ResourceLink.description',
+                'ResourceLink.id',
+                'ResourceLink.title',
+                'ToolConsumerProfile.url',
+                'User.id',
+                'User.image',
+                'User.username'
+            ],
+            'service_offered' => [
+                '@type' => 'RestService',
+                '@id' => 'tcp:Outcomes.LTI1',
+                'endpoint' => $this->url_for('course/lti/outcome/' . $id),
+                'format' => ['application/vnd.ims.lti.v1.outcome+xml'],
+                'action' => ['POST']
+            ]
+        ];
+
+        $this->set_content_type('application/vnd.ims.lti.v2.toolconsumerprofile+json');
+        $this->render_text(json_encode($profile));
+    }
+
+    /**
+     * Handle outcome service callback request by the LTI tool.
+     *
+     * @param   int $id    link id
+     */
+    public function outcome_action($id)
+    {
+        require_once 'vendor/oauth-php/library/OAuthRequestVerifier.php';
+
+        $lti_data = LtiData::find($id);
+
+        OAuthStore::instance('PDO', [
+            'dsn' => 'mysql:host=' . $GLOBALS['DB_STUDIP_HOST'] . ';dbname=' . $GLOBALS['DB_STUDIP_DATABASE'],
+            'username' => $GLOBALS['DB_STUDIP_USER'],
+            'password' => $GLOBALS['DB_STUDIP_PASSWORD']
+        ]);
+
+        $oarv = new OAuthRequestVerifier();
+        $oarv->verifySignature($lti_data->getConsumerSecret(), false, false);
+
+        // fetch and parse POST data
+        $message = file_get_contents('php://input');
+        $envelope = new SimpleXMLElement($message);
+        $header = current($envelope->imsx_POXHeader->children());
+        $body = current($envelope->imsx_POXBody->children());
+
+        $message_id = trim($header->imsx_messageIdentifier);
+        $operation = $body->getName();
+        $user_id = trim($body->resultRecord->sourcedGUID->sourcedId);
+        $grade = new LtiGrade([$id, $user_id]);
+
+        $this->message_id = uniqid();
+        $this->message_ref = $message_id;
+        $this->status_severity = 'status';
+        $this->status_code = 'success';
+        $this->operation = $operation;
+
+        if (!CourseMember::exists([$lti_data->course_id, $user_id])) {
+            $this->status_severity = 'error';
+            $this->status_code = 'failure';
+            $this->description = 'incorrect sourcedId: ' . $user_id;
+        } else if ($operation === 'readResultRequest') {
+            if ($grade->isNew()) {
+                $this->status_severity = 'error';
+                $this->status_code = 'failure';
+                $this->description = 'no score found for: ' . $user_id;
+            } else {
+                $this->score = $grade->score;
+                $this->description = 'score has been read';
+            }
+        } else if ($operation === 'replaceResultRequest') {
+            $grade->score = (float) $body->resultRecord->result->resultScore->textString;
+            $grade->store();
+            $this->description = 'score has been updated';
+        } else if ($operation === 'deleteResultRequest') {
+            $grade->delete();
+            $this->description = 'score has been deleted';
+        } else {
+            $this->status_severity = 'error';
+            $this->status_code = 'unsupported';
+            $this->description = 'operation not supported: ' . $operation;
+        }
+
+        $this->set_content_type('text/xml; charset=UTF-8');
+        $this->set_layout(null);
+    }
+
+    /**
+     * Display the (simple) LTI gradebook.
+     */
+    public function grades_action()
+    {
+        Navigation::activateItem('/course/lti/grades');
+
+        $this->lti_data_array = LtiData::findByCourse_id($this->course_id, 'ORDER BY position');
+
+        if ($this->edit_perm) {
+            $this->desc = Request::int('desc');
+            $this->members = CourseMember::findByCourseAndStatus($this->course_id, 'autor');
+
+            if ($this->desc) {
+                $this->members = array_reverse($this->members);
+            }
+
+            $widget = Sidebar::get()->addWidget(new ExportWidget());
+            $widget->addLink(
+                _('Ergebnisse exportieren'),
+                $this->url_for('course/lti/export_grades'),
+                Icon::create('download')
+            );
+        } else {
+            $this->render_action('grades_user');
+        }
+
+        Helpbar::get()->addPlainText('', _('Auf dieser Seite können Sie die Ergebnisse sehen, die von LTI-Tools zurückgemeldet wurden.'));
+    }
+
+    /**
+     * Export grades from the gradebook in CSV format.
+     */
+    public function export_grades_action()
+    {
+        $lti_data_array = LtiData::findByCourse_id($this->course_id, 'ORDER BY position');
+
+        $columns = [_('Nachname'), _('Vorname')];
+
+        // add one column for each LTI tool block
+        foreach ($lti_data_array as $lti_data) {
+            $columns[] = $lti_data->title;
+        }
+
+        $data = [$columns];
+        setlocale(LC_NUMERIC, $_SESSION['_language'] . '.UTF-8');
+
+        foreach (CourseMember::findByCourseAndStatus($this->course_id, 'autor') as $member) {
+            $row = [$member->nachname, $member->vorname];
+
+            foreach ($lti_data_array as $lti_data) {
+                if ($grade = $lti_data->grades->findOneBy('user_id', $member->user_id)) {
+                    $row[] = (float) $grade->score;
+                } else {
+                    $row[] = '';
+                }
+            }
+
+            $data[] = $row;
+        }
+
+        $filename = Context::get()->name . ' - ' . _('Ergebnisse') . '.csv';
+        $this->render_csv($data, $filename);
+    }
+}