Command to change volume to specific value in Linux

[tibhel]

Hi! 

I would like to create a shell script to set the Spotify internal volume setting to a specific value, how is it possible? I have seen it on Mac but not on linux...

Thanks in advance

[jooon]

It is not possible yet. Volume is a property that you can change in the MPRIS D-Bus interface so it would be ideal for setting the Spotify volume in a shell script. https://specifications.freedesktop.org/mpris-spec/latest/Player_Interface.html#Property:Volume

However, the Spotify client has not implemented that yet.

[tibhel]

Thank you for your answer, yes I have played around with Dbus but the Volume property gives me an error every time when calling: (e.g 0.2 as value) 

$player->Volume(0.2);

Error: 

org.freedesktop.DBus.Error.InvalidArgs: Error setting property 'Volume': Expected type 'd' but got 's'

What data type should be in the argument..? 

Thanks

[jooon]

That looks more like the dbus library in perl/php/whateverlanguage you are using has a bug. It sends something as a string 's' when it should send it as a double 'd', even though it looks like you are giving it something that would be a float/double in many languages. But it doesn't really matter if you fix that.

This will correctly send the the MPRIS D-bus Volume property change to Spotify, but Spotify will just ignore it.

dbus-send --print-reply --session --dest=org.mpris.MediaPlayer2.spotify /org/mpris/MediaPlayer2 org.freedesktop.DBus.Properties.Set string:org.mpris.MediaPlayer2.Player string:Volume variant:double:0.2

[abmantis]

Still not working as of today 😕