gubar

A hackable Swaybar generator, written and configured with Guile Scheme.

Try it using Guix shell

cd gubar/
guix shell
autoreconf -vif && ./configure
./pre-inst-env gubar

Installing

Dependencies

• Guile 3
• guile-fibers
• guile-json

Guix

This will install gubar and put it in your profile PATH:

cd gubar/
guix package -f guix.scm

Integrating with swaybar

Once gubar is installed, add the following to your Sway config:

bar {
    ...
    status_command gubar
    ...

Configuration

Gubar will look for a config file in ~/.config/gubar/config.scm before falling back to the default config, which is just the system time.

The config.scm file must return a list of gublocks in the order in which you want them displayed, from left to right. You may use the bundled blocks in (blocks/)[./src/gubar/blocks/] or create your own using the helper procedure gublocks that exists in the gubar gublock module.

gublock

A gublock is the fundamental building block of Gubar.

⚠️ Subject to Change
The gublock interface is unstable and may change at any point

(gublock 
    #:block [block] 
    #:interval [interval]
    #:procedure [procedure]
    #:click-handler [click-handler]
    #:signal [signal])

The effects of the keys are as follows:

Key	Description	Example
block	Initial block represented as an assoc list.	'(("full_text" . "foo"))
interval	Time in seconds in which this block updates	seconds or 'persistent
procedure	The main procedure that will be run after interval. Receives a <block> and returns a <block> record.	(lambda (block) block)
click-handler	The procedure that is run when this block is clicked. The block must have its name field set.	(lambda (event block) (block))
signal	SIGRTIMIN offset that this block will be listening on and refresh on. Can be triggered by sending a SIGRTMIN+signal to the guile process running gubar -- pkill -SIGRTMIN+signal -f -n gubar.scm	2

Examples

All keys are optional, so the most basic block with no text at all is (gublock). Here's a block that the number of seconds it has been active:

(gublock
 #:interval 1 ; update each second
 #:procedure
 (let ((counter 0))
   (lambda (block)
     (set! counter (+ counter 1))
     (set-block-full-text! block (number->string counter))
     block)))

And here's a block that shows a random number every time you click it:

(gublock
 #:block (("full_text" . "Click me!")
          ("name" . "randomizer"))
 #:click-handler
 (lambda (_ block)
   (set-block-full-text! block (number->string (random 1000000)))
   block))

Built-in Blocks

Block	Declaration	Info
battery	(battery #:key (format "~a ~a%") (nerd-icons #f))	Uses /sys/class/power_supply/AC/online and /sys/class/power_supply/BAT0/capacity
date-time	(date-time #:key (format "%c") (interval 1))	Defaults: format %c, info 1
label	(label text #:key color)	Color should be an RGB string "#RRGGBB"
network-manager-wifi	(network-manager-wifi #:key (ssid #f))	Uses nmcli -t -f SSID,IN-USE,SIGNAL device wifi list --rescan auto to gather info
volume	(volume-pipewire #:key (signal 2))	Uses pactl -f json list sinks and pactl get-default-sink to gather info
xkb-layout	(xkb-layout #:key (signal 3) (alias-pairs '()))	Uses swaymsg -rt get_inputs to gather info. alias-pairs are for mapping the layout index to an alias to be displayed

Example Config

(use-modules (gubar gublock)
             (gubar blocks date-time)
             (gubar blocks battery)
             (gubar blocks label)
             (gubar blocks volume-pipewire)
             (gubar blocks network-manager-wifi)
             (gubar blocks xkb-layout)
             (gubar swaybar-protocol))

(list
 (date-time #:interval 60 #:format "%a %b %d %Y %-I:%M %p")
 (network-manager-wifi)
 (volume-pipewire)
 (xkb-layout #:alias-pairs '((0 . "lang1") (1 . "lang2")))
 (battery #:nerd-icons #t)
 (label "some text"))

Corresponding swayconfig

For the modules that require signals:

# Volume control
bindsym --locked  XF86AudioMute exec pactl set-sink-mute @DEFAULT_SINK@ toggle
bindsym --release XF86AudioMute exec pkill -SIGRTMIN+2 -f -n gubar.scm
bindsym --locked  XF86AudioLowerVolume exec pactl set-sink-volume @DEFAULT_SINK@ -5%
bindsym --release XF86AudioLowerVolume exec pkill -SIGRTMIN+2 -f -n gubar.scm
bindsym --locked  XF86AudioRaiseVolume exec pactl set-sink-volume @DEFAULT_SINK@ +5%
bindsym --release XF86AudioRaiseVolume exec pkill -SIGRTMIN+2 -f -n gubar.scm

# Switch layout
bindsym --release $mod+Control_R exec swaymsg input type:keyboard \
                                      xkb_switch_layout next && \
                                      pkill -SIGRTMIN+3 -f -n gubar.scm

Bar declaration:

bar {
    ...
    status_command "guix shell guile -f /path/to/gubar/guix.scm -- /path/to/gubar/src/gubar.scm"
    ...
}

Contributing

This project uses Guile Hall to generate the files necessary for the GNU Build System. If you are contributing new source files, e.g., new gublock definitions, the files must be regenerated as follows.

# Add new file
touch gubar/blocks/my-new-block.scm

# Register new file in hall.scm
hall add gubar/blocks/my-new-block.scm

# Rebuild GNU Build System files
hall build -xf

TODO

• Make configuration more ergonomic with some kind of syntax for defining blocks, instead of having to use assoc lists.
• Try to use channels to send click updates to a block instead of finding the block and updating manually (maybe)
• Better error handling or assertions
• Fix guix.scm to install with gnu-build-system so that we can install the script as a program with default configs, docs, etc.