Bug 716696 – media-video/mpv-0.32.0 doesn't have a runtime use flag for youtube-dl urls

• Product: Gentoo Linux
• Status: RESOLVED INVALID

[Description Matthew Schultz 2020-04-08 14:11:20 UTC]

Trying to run a youtube streaming url through mpv presents with an error that looks like this:

Failed to open http://streams.pacifica.org:9000/live_64.
[ytdl_hook]  
[ytdl_hook] youtube-dl failed: not found or not enough permissions 

The ebuild has a log message buried in the post install that mentions this:

If you want URL support, please install net-misc/youtube-dl.

I think instead of including message at the end of post install is not the best way to handle this.  I think a runtime useflag should be added to depend on net-misc/youtube-dl to make it more obvious that that program needs to be installed if you want mpv to support youtube url streams.



Reproducible: Always

[Comment 1 Mikle Kolyada (RETIRED) 2020-04-08 20:31:47 UTC]

Introducing a use flag would result in needless rebuilds from users without any benifit as this flag not gonna affect anything but pull a dependency.

[Comment 2 Matthew Schultz 2020-04-08 21:13:37 UTC]

(In reply to Mikle Kolyada from comment #1)
> Introducing a use flag would result in needless rebuilds from users without
> any benifit as this flag not gonna affect anything but pull a dependency.

I don't understand how a runtime error is better.  I got the error when trying to play a stream and it was not obvious what to do.  I thought it was a bug at first.  Wouldn't it be better to have it documented as a feature in a useflag instead of having to read the mpv ebuild to determine that you need to manually pull in that runtime dependency?

[Comment 3 Mikle Kolyada (RETIRED) 2020-04-09 07:55:51 UTC]

(In reply to Matthew Schultz from comment #2)
> (In reply to Mikle Kolyada from comment #1)
> > Introducing a use flag would result in needless rebuilds from users without
> > any benifit as this flag not gonna affect anything but pull a dependency.
> 
>  Wouldn't it be better to have it documented as a feature in
> a useflag instead of having to read the mpv ebuild to determine that you
> need to manually pull in that runtime dependency?

No, because youtube-dl does not change the installation binary, you will have to rebuild mpv just because you installed youtube-dl, if you install youtube-dl manually the impact is the same, but you do not have to rebuild mpv due to depgraph changes.

[Comment 4 Matthew Schultz 2020-04-09 13:20:31 UTC]

(In reply to Mikle Kolyada from comment #3)
> (In reply to Matthew Schultz from comment #2)
> > (In reply to Mikle Kolyada from comment #1)
> > > Introducing a use flag would result in needless rebuilds from users without
> > > any benifit as this flag not gonna affect anything but pull a dependency.
> > 
> >  Wouldn't it be better to have it documented as a feature in
> > a useflag instead of having to read the mpv ebuild to determine that you
> > need to manually pull in that runtime dependency?
> 
> No, because youtube-dl does not change the installation binary, you will
> have to rebuild mpv just because you installed youtube-dl, if you install
> youtube-dl manually the impact is the same, but you do not have to rebuild
> mpv due to depgraph changes.

Point taken.  It's too bad portage doesn't have the ability to provide a useflag dependency but not require a rebuild.