frame.php

<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle 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 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * Proview
 *
 * This module provides support for remote proctoring quizzes and assessments using Proview
 *
 * @package    local_proview
 * @copyright  Talview, 2020
 * @author     Talview Inc.
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

// Include config.php.
// @codingStandardsIgnoreStart
// Let codechecker ignore the next line because otherwise it would complain about a missing login check
// after requiring config.php which is really not needed.
require_once('../../config.php');
// @codingStandardsIgnoreEnd

// Globals.
global $PAGE, $COURSE;

$PAGE->set_context(context_system::instance());

$PAGE->set_pagelayout('embedded');
$PAGE->set_heading("Proview Quiz");
$PAGE->set_url('/local/proview/frame.php');

$sesskey = sesskey();

echo $OUTPUT->header();

?>

<iframe id="contentIFrame" title="Iframe application" style="width: 98vw; height:95vh; border: 0px;">
  <p>Your browser does not support iframes.</p>
</iframe>
<script src="https://browser.sentry-cdn.com/5.18.1/bundle.min.js" 
        integrity="sha384-4zdOhGLDdcXl+MRlpApt/Nvfe6A3AqGGBil9+lwFSkXNTv0rVx0eCyM1EaJCXS7r" 
        crossorigin="anonymous">
</script>
    <script>
    var childOrigin = '*';
    Sentry.init({
      dsn: 'https://61facdc5414c4c73ab2b17fe902bf9ba@o286634.ingest.sentry.io/5304587'
    });
    // Defining function for event handling on postMessage from any window
    function receiveMessage(event) {
      try {
        if(event.data.type == 'startProview') {
            startProview(...event.data.args);
        }
        if(event.data.type == 'stopProview') {
            stopProview(event.data.url);
        }       
      } catch (error) {
        if( error && error.error ) {
          Sentry.captureException(error.error);
        } else {
          Sentry.captureException(error);
        }
        document.getElementById('contentIFrame').src = 'https://pages.talview.com/proview/error/index.html'; 
      }
    }

    window.addEventListener("message", receiveMessage, false);

    //Javascript function to start proview invoked upon postMessage from iframe


    function startProview(
        authToken, 
        profileId, 
        session, 
        session_type = "ai_proctor", 
        proview_url, 
        additionalInstruction,
        reference_link,
        proview_playback_url,
        skipHardwareTest,
        previewStyle, 
        clear) {
        const referenceLinksArray = reference_link.match(/\[([^\]]+)\]\(([^)]+)\)/g)?.map(markdownLink => {
            const match = markdownLink.match(/\[([^\]]+)\]\(([^)]+)\)/);
            if (match) {
                const caption = match[1];
                const url = match[2];
                return { 'url': url, 'caption': caption };
            }
            return null;
        }).filter(link => link !== null);
      let url = proview_url || '//cdn.proview.io/init.js';
      document.getElementById('contentIFrame').src = window.iframeUrl;
      //script to load the proview STARTS
      (function(i,s,o,g,r,a,m){i['TalviewProctor']=r;i[r]=i[r]||function(){
        (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
        m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
      })(window,document,'script',url,'tv');
        tv('init', authToken,{
            profileId: profileId,
            session: session,
            session_type: session_type,
            additionalInstruction: additionalInstruction,
            referenceLinks: JSON.stringify(referenceLinksArray),
            clear: clear || false,
            skipHardwareTest: skipHardwareTest || false,
            previewStyle: previewStyle || 'position: fixed; bottom: 0px;',
            initCallback: createCallback(proview_playback_url, profileId, session_type)/* onProviewStart */
      });
    }

    function createCallback (proview_playback_url, profile_id, session_type) {
      return function onProviewStart(err, id) {
        try {
          const urlParams = new URLSearchParams(window.location.search);
          window.ProviewStatus = 'start';
          let iframeWindow = document.getElementById('contentIFrame').contentWindow;

          //Lock quiz logic STARTS
          const button = iframeWindow.document.getElementById('id_quizpassword');
          if( button ) { //checking if the password is enabled for the quiz or not
            button.value = window.quizPassword; //fetching the password value from the window object
            iframeWindow.document.getElementById('mod_quiz_preflight_form').submit(); //submitting the password form
          }
          const id_submitbutton = iframeWindow.document.getElementById('id_submitbutton');
          if( id_submitbutton ) { //handle if the test is timed quiz
            id_submitbutton.click();//submitting the form
          }
          //Lock quiz logic ENDS
          iframeWindow.postMessage({
            type: 'startedProview',
            args: [
              err,   //Error on proview stating, if any
              id     // Playback ID
            ]
          }, childOrigin);

          const arr = {
            "user_id"       : profile_id,
            "quiz_id"       : urlParams.get('quizId'),
            "proview_url"   : proview_playback_url+'/'+id,
            "sesskey"       : "<?php echo $sesskey ?>",
            "proctor_type"  : session_type
          }
          const xmlhttp = new XMLHttpRequest();
          
          let retries=5;
          function run(){
            xmlhttp.onreadystatechange = function() {
              if (xmlhttp.readyState === 4) {
              }
              if (xmlhttp.status == 404) {
                if (retries > 0) {
                  retries-=1;
                  run();
                }else if(xmlhttp.readyState === 4) {
                    Sentry.captureException(new Error(xmlhttp));
                }
              }
            }
            xmlhttp.open("POST","datastore.php",true);
            xmlhttp.send(JSON.stringify(arr));
          }
          run();
        } catch (error) {
          console.log("Enter catch")
          if( error && error.error ) {
            Sentry.captureException(error.error);
          } else {
            Sentry.captureException(error);
          }
          document.getElementById('contentIFrame').src = 'https://pages.talview.com/proview/error/index.html'; 
        }
      }
    }

    function stopProview(url) {
      //Post message to application loaded into application on recording stop
      if ( window.ProviewStatus && window.ProviewStatus == 'start') {
        ProctorClient3.stop(function() {
            window.ProviewStatus = 'stop';
            document.getElementById('contentIFrame').contentWindow.postMessage({
                type: 'stoppedProview',
                url: url
            }, childOrigin);
            window.location.href = url;
        });
      } else {
          document.getElementById('contentIFrame').contentWindow.postMessage({
              type: 'stoppedProview',
              url: url
          }, childOrigin);
          window.location.href = url;
      }
    }
    (function() {
      try {
        const urlParams = new URLSearchParams(window.location.search);
        window.iframeUrl = urlParams.get('url');
        const xmlhttp = new XMLHttpRequest();
        
        function run(){
          xmlhttp.onreadystatechange = function() {
            if (xmlhttp.readyState === 4 && this.status == 200) {
              response=xmlhttp.responseText;
              response=JSON.parse(response);
              window.quizPassword = response.quiz_password;
              startProview(response.token, response.profile_id, response.session_id, response.session_type, response.proview_url, response.instructions, response.reference_link, response.proview_playback_url);
            }
          }
          xmlhttp.open("GET", "datastore.php?quiz_id=" + urlParams.get('quizId') + "&sesskey=" + "<?php echo $sesskey?>" , true);
          xmlhttp.send();
        }
        run();
      } catch (error) {
        if( error && error.error ) {
          Sentry.captureException(error.error);
        } else {
          Sentry.captureException(error);
        }
        document.getElementById('contentIFrame').src = 'https://pages.talview.com/proview/error/index.html'; 
      }
    })();
</script>


<?php echo $OUTPUT->footer();