I want to run my Quarkus app from a systemd service

[VicVerevita]

Hello! I've been trying to set up my Quarkus app to run at startup on a Rocky Linux machine. I put it in the /opt directory and gave all rights to my user.

Basically, the app is supposed to play videos, ones that are local and others that are in a directory adjacent to the app. The app is supposed to play the "external" videos as soon as they are preloaded.

Now for the problem I ran into:
When I try to run the .jar file with /path/to/java -jar /path/to/app - all is working well, all videos are playing as intended.
When I try to run the .jar file from the service, with the same command (no sudo, because I don't want to run it as root - I have also seen that root misbehaves with the DISPLAY env variable) - only the local videos work. The external videos do not play by any means.

Now this is my service:

[Unit]
Description=DMR Service

[Service]
Environment=JAVA_HOME=/opt/app/platform/dmr/java_vm
WorkingDirectory=/opt/app/platform/dmr/dmr_app
ExecStart=/opt/app/platform/dmr/java_vm/bin/java -jar /opt/app/pkg_mirror/dmr-runner.jar
Restart=on-failure
RestartSec=15s
TimeoutSec=300
StandardOutput=journal
StandardError=journal
Environment=XAUTHORITY=/home/ops/.Xauthority
Environment=DISPLAY=:0
Environment=.local/bin:/home/ops/bin:/usr/local/bin:/usr/bin:/usr/local/sbin:/usr/sbin
Environment=GTK_IM_MODULE=ibus
Environment=QT_IM_MODULE=ibus
Environment=GDK_BACKEND=x11
AmbientCapabilities=CAP_SYS_ADMIN
User=ops
Group=ops

[Install]
WantedBy=multi-user.target

My first presumption was that - using ffmpeg for my codecs, needed exactly for the external videos - the path to it was wrong or something. But I made a service to ffplay the "external" video and it works, so ffmpeg is not the problem.
My presumption now is that I am missing some env variable that stops the videos from being able to play.

Does anyone have any solutions to this, please? I've been racking my brains about it for some days now 😢

[VicVerevita]

Found the solution.

1. The "local" videos didn't have any audio, while the "external" ones did. Added a few more logs and found that no audio device could be open for playback
2. Rocky Linux uses pipewire as an audio driver. Found the environment variables here and set the XDG_RUNTIME_DIR to the value that was also set for the user (found using set command).

Everything works as intended now.

[gsmet]

Thanks for sharing your solution. Even if a bit specific, it can certainly be useful to others.