Redshift crashes after starting it as a user service

[Jacotsu]

When i start the service with systemctl --user start redshift it crashes with the following log

• I have checked the FAQ and my issue is not mention there.

To Reproduce
Steps to reproduce the behavior:

1. Install redshift, wlroots and sway version 1.1-rc1-51-gf5d1c272
2. Set adjustment-method=wayland in .config/redshift.conf
3. Start logging with journalctl --user -u redshift
4. Start the service with systemctl --user start redshift
5. See error

Expected behavior
Automatic wayland display detection

Error output/logs/screenshots

ott 25 17:44:42 stufa systemd[3362]: Started Redshift display colour temperature adjustment.
ott 25 17:44:42 stufa redshift[3818]: Could not connect to wayland display, exiting.
ott 25 17:44:42 stufa redshift[3818]: Failed to start adjustment method wayland.
ott 25 17:44:42 stufa systemd[3362]: redshift.service: Main process exited, code=exited, status=1/FAILURE
ott 25 17:44:42 stufa systemd[3362]: redshift.service: Failed with result 'exit-code'.
ott 25 17:44:42 stufa systemd[3362]: redshift.service: Service RestartSec=100ms expired, scheduling restart.
ott 25 17:44:42 stufa systemd[3362]: redshift.service: Scheduled restart job, restart counter is at 4.

Software versions (please complete the following information):

• OS: Linux
• Redshift version: 1.12
• Distribution: Ubuntu 19.10
• Redshift installed from: PPA

Possible Fix
By using the following service file redshift starts normally as a user service and works

[Unit]
Description=Redshift display colour temperature adjustment
Documentation=http://jonls.dk/redshift/
After=display-manager.service

[Service]
ExecStart=env WAYLAND_DISPLAY=wayland-0 /usr/local/bin/redshift
Restart=always

[Install]
WantedBy=default.target

Probably there's a better way to fix this issue

[WhyNotHugo]

There are two things that you'd need to do to work around this:

1. Make sure your WAYLAND_DISPLAY env setting gets exported before services start up. You can achieve this with systemctl --user import-environment.
2. Looks like WantedBy=default.target is wrong. This will make redshift start as soon as your session starts, without waiting for your graphical session to start. It should be WantedBy=graphical-session.target.

I'll put a PR up to update the service file for the second item. That aside, this is what I have as a last line of sway/config, in case you're using sway:

exec "systemctl --user import-environment; systemctl --user start graphical-session.target"