A userscript to extract video URLs from video embedded into RWTHonline, which are not uploaded as regular files.

rwthmoodle_video_urls.user.js

// ==UserScript==
// @name         RWTHmoodle Opencast Video Catcher
// @namespace    https://literalchaos.de
// @version      0.2
// @description  Captures video urls played by the player embedded into RWTHmoodle
// @author       Jan Scheiper
// @match        https://moodle.rwth-aachen.de/*
// @match        https://engage.streaming.rwth-aachen.de/*
// @grant        GM_webRequest
// @grant        GM_xmlhttpRequest
// @downloadURL    https://gist.github.com/jangxx/ac4985fbfbf8b44bf12854768b7939c0/raw/rwthmoodle_video_urls.user.js
// ==/UserScript==

(function() {
    'use strict';

    if (window == window.top && window.location.href.includes("moodle")) {
        let containerNode = document.createElement("div");
        containerNode.innerHTML = `<b>Captured video URLs:</b>`;
        containerNode.style.cssText = "position: absolute; top: 50px; right: 10px; background-color: white; padding: 10px; border-width: 1px; border-style: solid; border-color: black";

        let listNode = document.createElement("ul");
        listNode.style.cssText = "margin: 5px 0px";
        containerNode.appendChild(listNode);

        let elemAppended = false;

        window.addEventListener("message", msgRaw => {
            let msg = JSON.parse(msgRaw.data);

            if (msg.type == "captured") {
                let listElem = document.createElement("li");
                listElem.innerHTML = `<a href="${msg.url}">Download</a> <input type="text" value="${msg.title}" onclick="this.select()" size="60" readonly>`;
                listElem.style.cssText = "margin: 2px 0px;";
                listNode.appendChild(listElem);

                if (!elemAppended) {
                    elemAppended = true;
                    document.querySelector("nav.fixed-top.navbar").appendChild(containerNode);
                }
            }
        });
    } else {
        let captured = [];

        GM_webRequest([
            { "selector": "*episode.json*" , "action": { redirect: { from: "(.*)", to: "$1" } } } // redirect to same url to be able to get the url and it's parameters
        ], (info, message, details) => {
            let url = details.url;

            if (!captured.includes(url)) {
                captured.push(url);

                let xhr = new XMLHttpRequest();
                xhr.open("GET", url);
                xhr.send();

                xhr.addEventListener("load", () => {
                    let body;
                    try {
                        body = JSON.parse(xhr.response);
                    } catch(e) {
                        console.error(e);
                        return;
                    }

                    let tracks = body["search-results"].result.mediapackage.media.track;
                    let track = tracks.find(t => t.url.includes(".mp4"));

                    let title = body["search-results"].result.dcTitle;

                    if (track != null) {
                        console.log(`Captured: ${title}`);
                        console.log(track.url);
                        window.top.postMessage(JSON.stringify({
                            type: "captured",
                            title,
                            url: track.url
                        }), "*");
                    }
                });
            }
        });
    }
})();