(custom) keypress detection errors

[rien333]

Custom keypress detection, and possibly also the detection of (some) default keypresses, seems to be broken. Given the following example code from the README:

...
@player.on_key_press('q')
def my_q_binding():
    print('THERE IS NO ESCAPE')
...

I get this error when pressing q:

TypeError: _handle_key_binding_message() takes from 3 to 4 positional arguments but 5 were given
Traceback (most recent call last):
  File "/usr/lib/python3.8/site-packages/mpv.py", line 474, in _event_loop
    message_handlers[target](*args)
TypeError: _handle_key_binding_message() takes from 3 to 4 positional arguments but 5 were given

System info

$ uname -mor
5.3.13-arch1-1 x86_64 GNU/Linux
$ mpv --version
mpv 0.30.0-210-g7c6570402b Copyright © 2000-2019 mpv/MPlayer/mplayer2 projects
 built on Tue Nov 26 11:50:51 CET 2019
ffmpeg library versions:
   libavutil       56.35.101
   libavcodec      58.62.100
   libavformat     58.35.100
   libswscale      5.6.100
   libavfilter     7.66.100
   libswresample   3.6.100
ffmpeg version: N-95734-gbfa8272f40

I tested this with python-mpv from git master.

[jaseg]

This is due to the upstream change in mpv-player/mpv@21f2468 . I've fixed this in master and published v0.4.0 on PyPI. The fix is compatible with older mpv versions.

Thank you very much for your detailed report!

[rien333]

Wow, thanks for the super quick fix!

Possibly on topic: I remember being able to send the python-mpv module key presses right from the terminal. Key press detection now works again when a video is in focus, but when I'm e.g. playing an audio file in a terminal app, I have no way to control mpv (which I'm pretty sure did work a little while ago).

I'm creating the mpv object with player = mpv.MPV(input_default_bindings=True, input_vo_keyboard=True), FYI, and I'm running python-mpv with the commits you just pushed.

If I'm wrong, and the terminal was never able to straightforwardly send keypresses to a mpv instance via this module (i.e. by just registering @player.on_key_press('SPACE')), then what is the recommended way to detect keypresses from the terminal?

[jaseg]

I'm not sure if that ever worked. I just tried --input-terminal and that didn't seem to work. Probably the best way to do this would be to grab raw terminal key presses using something like this, then mapping to mpv key names, then use the keypress input command via mpv.command.

Another, easier way to control audio playback would be to use --input-vo-keyboard and simply force a window with --keep-open=always and `--force-window'.

[rien333]

Weird, I would swear @player.on_key_press('SPACE') once allowed me to pause mpv from the terminal, but I'm probably misremembering then. Thanks for your method, I'll try it now.

[jaseg]

It might be that at some point libmpv grabbed stdin and did actually handle input like that. I just couldn't find any references changing in the mpv repo. Technically it would be possible.

[jaseg]

#122 contains a solution to this. The trick is to use both terminal=True and input_terminal=True when initializing libmpv.