Callbacks to external tools (here sketchybar)

[fgeck]

Hey,

I am experimenting a lot with kanata with the goal that on layer change and of modifier active (home row mods) I would like to see that in sketchybar.

to trigger an update I have to call: sketchybar --trigger kbd_layer LAYER=base STATE=on or sketchybar --trigger kbd_mod LAYER=num STATE=off

I have SKHD running that catches some keys, e.g.:

# Modifier ON indicators (combo excludes the modifier being activated)
alt + ctrl + shift - q : sketchybar --trigger kbd_mod MOD=cmd STATE=on
ctrl + cmd + shift - w : sketchybar --trigger kbd_mod MOD=alt STATE=on
alt + cmd + shift - e : sketchybar --trigger kbd_mod MOD=ctrl STATE=on
ctrl + alt + cmd - t : sketchybar --trigger kbd_mod MOD=shift STATE=on

# Modifier OFF indicators (hyper+1=cmd, hyper+2=alt, hyper+3=ctrl, hyper+4=shift)
ctrl + alt + shift + cmd - 1 : sketchybar --trigger kbd_mod MOD=cmd STATE=off
ctrl + alt + shift + cmd - 2 : sketchybar --trigger kbd_mod MOD=alt STATE=off
ctrl + alt + shift + cmd - 3 : sketchybar --trigger kbd_mod MOD=ctrl STATE=off
ctrl + alt + shift + cmd - 4 : sketchybar --trigger kbd_mod MOD=shift STATE=off

My current approach was using kanata to send on hold and send on release not only the modifier, but also some weird key combos (e.g. hyper + q when using the a homerow mod).
Unfortunately it did not really lead to success. Either I was able to update sketchybar and the mods/layers did not work properly or vice versa.

My kanata config looks messy AF as I tried to fix my issue with claude, but I can link it here: https://github.com/fgeck/dotfiles-stow/blob/main/kanata/.config/kanata/kanata.kbd

My question is more: is there a general concept for such callbacks that I missed? Because then I could skip using SKHD and sending the weird combos.
Or are there any other ideas?
Finally I will get a QMK based keyboard soon and I will run into the same issue. Any ideas on that topic are highly welcome as well

[jtroo]

You can connect to Kanata via its TCP port and receive layer change notifications:

https://github.com/jtroo/kanata/blob/main/docs/config.adoc#event-notifications

Notifying on active modifiers doesn't exist in the TCP functionality though. No good ideas off the top of my head.

[fgeck]

Using the TCP port and a very small TCP server in between kanata and sketchybar works quite well.

For the modifier changes I used the push-msg function