Download Canvas Course Materials

Background

Throughout my time as an online CS student at Oregon State, all of the courses were delivered via Canvas. After completing my degree, I still had access to all of the courses that I took and wanted to download the modules for future reference. Thanks to the instructors for creating some excellent learning materials.

Initially, I thought exporting each page as pdf would be the ideal route. With chrome you can save a page as pdf directly from the command line using something like chromium-browser --headless --disable-gpu --print-to-pdf=file1.pdf http://www.example.com/. However, Canvas requires two-factor authentication which makes accessing the pages quite difficult. I also considered using Puppeteer but quickly ran into similar issues and ran out of patience. I finally settled on saving the pages as html since many of the pages included interactive javascript content and I had a quick hacky solution in mind.

Tutorial

The basic idea is to open each link from the “Modules” page into a new browser tab and save each of them.

You can obtain a list of all the anchor tags on the page from the console with the following javascript.

document.getElementsByClassName("ig-title title item_link")

To open each link into a new tab, you can use:

Array.from(
    document.getElementsByClassName("ig-title title item_link")
).forEach((e) => window.open(e, "_blank"));

However, firefox blocks popups by default. To enable popups go to Applications Menu -> Settings -> Privacy and Security -> Permissions -> Block pop-up windows. Even after adjusting this setting, firefox will only open 20 popup windows to open by default. To change this setting, navigate to about:config?filter=dom.popup_maximum and click “Accept the Risk and Continue”. Remember to change this setting back to 20 when you are done.

To automatically save each open tab to an html file, I used the firefox extension Save Selected Tabs to Files.

Before using the extension, be sure to adjust two more settings. First, tell firefox not to prompt you where to download each file. Applications Menu -> Settings -> Files and Applications -> Always ask where to save files. Also, adjust the preferences for the extension to not truncate the file names after x number of characters.