Start Spotify w/ Play/Pause key

spotifyPause.md

spotifyPause.sh

This short script allows the Play/Pause keyboard key to be also used to start Spotify (or any player of your choice with a bit of tweaking). I'm using Cinnamon's settings to reassign keys, but other distros may also have this feature

Setup

• Download/copy the script somewhere on your system
• chmod +x ./spotifyPause.sh to make it runnable
• Add the new keybinding [Cinnamon only]
  • Open cinnamon-settings keyboard (you can search for "Keyboard" in the start menu search if you don't like terminals)
  • Navigate to Shortcuts > Custom shortcuts
  • Add custom shortcut Name=[doesn't matter] Command=[path to the script]
  • Click the shortcut's name in the top list (it should already be selected)
  • Click on one of the unassigned slots below and press the Play/Pause button of your keyboard
  • If a warning dialog appears because the key is already assigned, press Continue. A key cannot be programmed to do two actions, but the script will send a Play/Pause signal when executed (2nd line), thus removing the need for the old keybinding
• Done !

How does it work

What I'm explaining below is quite basic. Only take the time to read it if you don't know bash or Linux in general !

#!/bin/bash

Shebang: When a file is chmod +xed, Linux considers it executable. This line tells the OS which binary should be used to interpret(=run) the file, here it is bash.

dbus-send --print-reply --dest=org.mpris.MediaPlayer2.spotify /org/mpris/MediaPlayer2 org.mpris.MediaPlayer2.Player.PlayPause

Play/Pause signal: This sends a Play/Pause signal to Spotify, which is what the default keybinding does. source

pidof spotify
if [ $? -ne 0 ]
then
  nohup spotify &
fi

Starting Spotify:

The first line runs a command which returns the PID (process id) of a process whose name is spotify. Here, we don't really care about it, you'll see why.

Then, we encounter an if statement, which checks if the variable $? is different from 0. $? is the status/exit code of the last command that was run. All Linux processes must return such a code when stopping. The convention is that 0 is returned when everything worked fine. In this case, if $? -ne 0, this implies that pidof spotify had encountered an error, which means that no process matching the name spotify was found. In other words, the code inside the if statement only runs if Spotify isn't running.

This code, nohup spotify &, starts Spotify as a background process, thanks to nohup and &. Here, "background" means that the script won't pause and wait for Spotify to stop, which would have been the default behavior if we just typed spotify.

spotifyPause.sh

#!/bin/bash
dbus-send --print-reply --dest=org.mpris.MediaPlayer2.spotify /org/mpris/MediaPlayer2 org.mpris.MediaPlayer2.Player.PlayPause
pidof spotify
if [ $? -ne 0 ]
then
  nohup spotify &
fi