Update on the issue "Stuck on Building Course Data"

[FaisalUmair]

Hello everyone. Sorry for my late response here. I do not actively maintain this project and get a very limited spare time from work. I have been receiving a lot of emails lately about the issue "Stuck on Building Course Data". I will work on the said issue this weekend. And hopefully, come up with a fix or at least an update on whats wrong and whether it can be fixed or not.

Originally posted by @FaisalUmair in #172 (comment)

[TheCrimsonborn]

Yeah, same. I hope the dev fixes it soon.

Edit: Oh sorry, you are already the dev. Thanks for the attention. Good luck.

[mthibaut-hbc]

Hello everyone. Sorry for my late response here. I do not actively maintain this project and get a very limited spare time from work. I have been receiving a lot of emails lately about the issue "Stuck on Building Course Data". I will work on the said issue this weekend. And hopefully, come up with a fix or at least an update on whats wrong and whether it can be fixed or not.

Originally posted by @FaisalUmair in #172 (comment)

Diagnostic is easy ! In https://github.com/FaisalUmair/udemy-downloader-gui/blob/master/assets/js/app.js at line 336 :

var lecture = response.asset.stream_urls;

For Video with DRM, response.asset.stream_urls is NULL so all next code lines using lecture variable return errors like in code block at line 339:

lecture.Video.forEach(function(val) {                      
if (val.label == "Auto") return;                      
qualities.push(val.label);                      
qualitySrcMap[val.label] = val.file;                    
});

For Video with DRM, You must use response.asset.media_sources

[narenawa]

GREATTTT..... waiting the update ...

[FaisalUmair]

@mthibaut-hbc I had a quick look at this yesterday. Not all media_sources are video files. And those are the ones which are encrypted. For now we can fix it from being stuck, but that means not all videos will be downloaded.

As I said, I will check this further during weekend, and see if we can do any better, if not then I will simply allow these files to skip for now.

[BasilTigris]

FaisalUmair i wish you to manage and keep your fantastic udeler tool alive! I cant wait for your good news, and start download the course i buy, good luck my friend and thank you very much!

[mthibaut-hbc]

@mthibaut-hbc I had a quick look at this yesterday. Not all media_sources are video files. And those are the ones which are encrypted. For now we can fix it from being stuck, but that means not all videos will be downloaded.

As I said, I will check this further during weekend, and see if we can do any better, if not then I will simply allow these files to skip for now.

@FaisalUmair True, for unencrypted videos type = "video/mp4" in media_sources. In encrypted videos, You need to take type = "application/dash+xml" in media_sources.

This where it's begin to be not standard! :
For unencrypted videos, no big deal, You just need to download the video from media_source->src
For encrypted video, You need to download the media_source->src file, extract all video & audio segments from this file, downloads these segments, concatenate them into a single file, unencrypt following audio & video file with right key and them finally ffmpeg them into a final video.

A lot of steps but UDEMY DRM is already a dead born baby. I have already tested it in python and it's work like a charm ...

[FaisalUmair]

@mthibaut-hbc Thank you for the helpful information and your work on testing it. I will give it a try this weekend, and see how it goes.

[mthibaut-hbc]

@mthibaut-hbc Thank you for the helpful information and your work on testing it. I will give it a try this weekend, and see how it goes.

@FaisalUmair , You are Welcome ! Seems that it's not a good idea to modify Udeler to skip DRM videos because I'm 100% sure that Udemy is in progress to DRM all courses. Some old courses I buy from 2018 was not DRM yesterday and now today, a large majority of the videos of these courses are DRM ... :-(

[ScrubDonkey]

@mthibaut-hbc Thank you for the helpful information and your work on testing it. I will give it a try this weekend, and see how it goes.

@FaisalUmair , You are Welcome ! Seems that it's not a good idea to modify Udeler to skip DRM videos because I'm 100% sure that Udemy is in progress to DRM all courses. Some old courses I buy from 2018 was not DRM yesterday and now today, a large majority of the videos of these courses are DRM ... :-(

Exactly what has happened, of all my dev courses all but a couple is fully DRM now. These range from 1-2 years old so they must be encrypting as they go.

[osonsur1]

@mthibaut-hbc I had a quick look at this yesterday. Not all media_sources are video files. And those are the ones which are encrypted. For now we can fix it from being stuck, but that means not all videos will be downloaded.
As I said, I will check this further during weekend, and see if we can do any better, if not then I will simply allow these files to skip for now.

@FaisalUmair True, for unencrypted videos type = "video/mp4" in media_sources. In encrypted videos, You need to take type = "application/dash+xml" in media_sources.

This where it's begin to be not standard! :
For unencrypted videos, no big deal, You just need to download the video from media_source->src
For encrypted video, You need to download the media_source->src file, extract all video & audio segments from this file, downloads these segments, concatenate them into a single file, unencrypt following audio & video file with right key and them finally ffmpeg them into a final video.

A lot of steps but UDEMY DRM is already a dead born baby. I have already tested it in python and it's work like a charm ...

@mthibaut-hbc

Great work! Would you be able to share the python script and necessary steps to run the script please?

Thanks in advance!

Keep up the good work! @mthibaut-hbc and @FaisalUmair

[BasilTigris]

great news!! when you ready please share..

[zackzinu]

Waiting for news. Thanks.

[ScrubDonkey]

If Udemy would just offer a proper "Offline Viewer" we wouldn't need to go through all this mess. I mean, didn't we purchase the videos already? I haven't pirated any of my videos to anyone. It really is just lazy.

[chicane71]

Hope it can work again soon and big thx for the effort already!!