Functionality for Disabling Services?

[ModestTG]

I had a quick question. I used this tool to convert a Minecraft docker server to Nix. I'm doing this on my desktop PC. I have servers that I could run this on but none of them are as fast or performant as my desktop PC. I was wondering if there was a way to disable the systemd service so that it doesn't start on reboot. I'd like to be able to start this service only when it's in use and be able to stop it to help save some resources if possible. Is something like that able to be done using this tool or would it require a whole re-engineer of how the services are created in systemd?

[aksiksi]

Yes, by default, the generated systemd services start on boot. You can disable this re-generating your config with -auto_start=false. Let me know if this doesn’t work as I personally don’t test it.

[ModestTG]

Ah, yes this should work. I thought I read the options closely to make sure one didn't exist before I asked but I didn't RTFM close enough 😅. Thanks for the quick reply! Great tool!

[ModestTG]

I was able to confirm that adding auto_start=false seems to both have prevented the service from starting on reboot and on rebuild. Thanks! It is strange though that the service still shows as enabled, I guess I would have expected it to not show that? But that could be my lack in understanding of how systemd services work

[aksiksi]

Yes, normally, you'd disable the systemd service to stop it from starting on boot. But the NixOS module opts to instead empty its wantedBy list, which basically means the systemd service is implicitly disabled. Not sure why they do it this way - not a systemd expert haha.

See: https://github.com/NixOS/nixpkgs/blob/nixos-unstable/nixos/modules/virtualisation/oci-containers.nix#L306

[aksiksi]

Also, I realized that it would be useful to control auto-start behavior at the Compose service level, so I added a small feature for this.

See: https://github.com/aksiksi/compose2nix?tab=readme-ov-file#auto-start-services-on-boot

[ModestTG]

What an awesome feature! Thank you very much!