Open edX (pdfbook link) - LTI Integration

lti-path.js

/*
Author: Zachary Trabookis
Date: 2018-08-02
Description: Update the relative course paths according to LTI usage or not. 
*/

function getCoursePathLTI(dataLink) {

    var isInIframe = (window.location != window.parent.location) ? true : false;
    console.log("In LTI = " + isInIframe);

    var coursePath = "";

    /* Divide up the LTI URL and rebuild the LMS course path.
    *  Only do this when serving content over LTI since this content will be within an iframe.
    * */
    if (isInIframe) {

        /* Find the LMS domain path
        *
        *  Course ID (Examples of different LMS course URLS)
        *  https://edx.readthedocs.io/projects/open-edx-building-and-running-a-course/en/latest/course_features/lti/lti_address_content.html
        *
        *  {key type}:{org}+{course}+{run}, for example, course-v1:edX+DemoX+2014
        *  https://example.com/lti_provider/courses/course-v1:CUCWD+FAA-PART-147-SGOS101+DEVELOPMENT/block-v1:CUCWD+ID201+DEVELOPMENT+type@sequential+block@5cec8fcf28364c32aa277ab1432mod04
        *
        *  {org}/{course}/{run}, for example, edX/DemoX/2014
        *  https://example.com/lti_provider/courses/CUCWD/MET101/2014_Spring/i4x://CUCWD/ID101/sequential/061b306f1796481fb2e3008038da1c3c
        * */

        /* Split based on 'lti_provider' since that's unique to the LTI URL path then assign course path to the URL domain to start. */
        var locationHREF = $(location).attr('href').split("lti_provider");
        coursePath = locationHREF[0];

        /* Find the course id based on different versions (i4x - prior version, course-id - new version) */
        var coursePathSubPath = locationHREF[1].split("/");
        (locationHREF[1].includes("i4x")) ?
            coursePath += coursePathSubPath[1] + "/" + coursePathSubPath[2] + "/" + coursePathSubPath[3] + "/" + coursePathSubPath[4] + "/":
            coursePath += coursePathSubPath[1] + "/" + coursePathSubPath[2] + "/";
    }
    else {
        /* When we're not using LTI we need this path to be relative to the current course. */
        coursePath = "../../../";
    }

    console.log("getCoursePathLTI = " + coursePath + dataLink);

    return coursePath + dataLink;
}

/*

<!-- Example include for the HTML Compoment. -->

<p>Please visit the <a href="#" class="eBook" data-link="pdfbook/0/chapter/1/1" target="_blank">eBook</a> for more information.</p>


<!-- Include LTI path override in top most HTML Component only. -->
<script src="/static/lti-path.js"></script>
<script>// <![CDATA[
$(document).ready(function () {

    // Rewrite the pdfbook link because of LTI 
 	$('a.eBook').attr("href", function () {
        return getCoursePathLTI( $(this).attr("data-link") );
    });
 
});
// ]]></script>

*/

pdfbook-lti-href.html

<!--
This code updates the 'href' for the anchor tag that's associated with the class "eBook". 
Important when you need this to link to continue to work with external LMS through LTI and Open edX instance.
-->

<ul>
    <li><a href="#" target="_blank" class="eBook" data-link="pdfbook/0/chapter/1/1">&nbsp;&nbsp;&nbsp;</a></li>
</ul>
    
<script>// <![CDATA[
$(document).ready(function () {
    var isInIframe = (window.location != window.parent.location) ? true : false;
    console.log("In LTI = " + isInIframe);

    var coursePath = "";

    /* Divide up the LTI URL and rebuild the LMS course path.
    *  Only do this when serving content over LTI since this content will be within an iframe.
    * */
    if (isInIframe) {

        /* Find the LMS domain path
        *
        *  Course ID (Examples of different LMS course URLS)
        *  https://edx.readthedocs.io/projects/open-edx-building-and-running-a-course/en/latest/course_features/lti/lti_address_content.html
        *
        *  {key type}:{org}+{course}+{run}, for example, course-v1:edX+DemoX+2014
        *  https://example.com/lti_provider/courses/course-v1:CUCWD+FAA-PART-147-SGOS101+DEVELOPMENT/block-v1:CUCWD+ID201+DEVELOPMENT+type@sequential+block@5cec8fcf28364c32aa277ab1432mod04
        *
        *  {org}/{course}/{run}, for example, edX/DemoX/2014
        *  https://example.com/lti_provider/courses/CUCWD/MET101/2014_Spring/i4x://CUCWD/ID101/sequential/061b306f1796481fb2e3008038da1c3c
        * */

        /* Split based on 'lti_provider' since that's unique to the LTI URL path then assign course path to the URL domain to start. */
        var locationHREF = $(location).attr('href').split("lti_provider");
        coursePath = locationHREF[0];

        /* Find the course id based on different versions (i4x - prior version, course-id - new version) */
        var coursePathSubPath = locationHREF[1].split("/");
        (locationHREF[1].includes("i4x")) ?
            coursePath += coursePathSubPath[1] + "/" + coursePathSubPath[2] + "/" + coursePathSubPath[3] + "/" + coursePathSubPath[4] + "/":
            coursePath += coursePathSubPath[1] + "/" + coursePathSubPath[2] + "/";
    }
    else {
        /* When we're not using LTI we need this path to be relative to the current course. */
        coursePath = "../../../";
    }

    console.log("coursePath = " + coursePath);

    $('a.eBook').attr("href", function () {
        return coursePath + $(this).attr("data-link");
    });
});
// ]]></script>