How to get notification from a udev rule on Hyprland?

[Xenorf]

Hello everyone,

I integrated dunst to my Hyprland setup and it works very well. The thing is I don't really understand how to notify a user running Hyprland (me) from another user like root or in a service or udev rule.

I tried to run the command with the following environment variables:

• DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/1000/bus
• WAYLAND_DISPLAY=wayland-1
• DISPLAY=:0

It just changed the error message that I am getting: Error receiving data: Connection reset by peer

Do you have any idea what I am doing wrong and if it is even possible to get this working on Hyprland?
Thank you!

[bynect]

Rather than dunst directly something like this should probably be done by the notify client, for example notify-send.

With a quick search I found this:
https://superuser.com/questions/342626/notify-send-to-other-user-on-the-same-system

But basically it tells you to change the user with sudo before sending the notification

[Xenorf]

Hey thank you for your answer.

Indeed, I managed to get it working by using the su command on top of exporting the variables but I didn't think it was the cleanest way to go.

[bynect]

glad you resolved.
do you send the notification when a new device is attached/removed? I also want to do this one day or another :)

[Xenorf]

Yes I wanted to get a notification when a usb key is attached and removed. The udev rule I am using looks like that:
ACTION=="add", SUBSYSTEMS=="usb", ENV{DEVTYPE}=="disk", RUN+="/bin/sh -c 'su <username> -c /home/<username>/.local/bin/usbmonitor.sh\ plug'"

The script I use exports the DBUS_SESSION_BUS_ADDRESS before running the dunstify command:
DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/1000/bus dunstify -I $icon "USB key plugged in"

[bynect]

Hello, I was doing something similar to you today and this is the script I have come up for now. This imports automatically the env vars from the dunst process.

#!/bin/bash

# Get envvar from another process
import_env() {
	for var in "$@"; do
		IFS='=' read key val < <(egrep -z "$var" /proc/$pid/environ)
		printf -v "$key" %s "$val"
		[[ ${!key} ]] && export "$key"
	done
}

notify() {
	local title=$1 body=$2

	# Assume dunst is the notification daemon for everyone
	declare -a pids=$(pgrep dunst)

	for pid in "${pids[@]}"; do
		(( pid )) || continue
		import_env XAUTHORITY USER DISPLAY DBUS_SESSION_BUS_ADDRESS
		su $USER -p -c "notify-send '$title' '$body'"
	done
}

notify "Attached new device" "Name: $1\nDevpath: $2"

the rule at the moment is

SUBSYSTEM=="usb", ACTION=="add", RUN+="/home/nect/script/udev-notify.sh '$name' '%p'"

However I still haven't figure out how to get a human readable name. Do you perchance know how?