Running dbus-broker-launch without systemd (the reprise)

[pharcosyle]

This has been discussed before (#183, #188). I'd like to run dbus-broker-launch without systemd.

My use case: I'm a Guix user (and developer, a bit) and I'd like to add an alternative option to use dbus-broker instead of dbus. Guix already jumps through some hoops to get dbus working as it uses elogind not systemd (although I use seatd) and I figure as long as we're hacking our way to functional distro dbus support anyway we might as well use a better implementation. I understand that there will be no service activation: that's fine, service activation sort of sucks so I/we already manually run daemons for pretty much everything (GNU Shepherd is nice for this).

I've patched the source so it compiles successfully against elogind. I've also naively updated that years-old PR (see pharcosyle@ec11a6b). I think the only thing I have left to do is create a unix socket that I pass to dbus-broker-launch and manage its lifecycle sensibly but I don't really know how to do that. I'd be grateful if anyone could give me some advice on how to go about completing this task or offer alternatives. Thank you!

[dvdhrm]

Hi! The test-suite in ./test/dbus/ already creates a dbus-broker instance, which it then runs tests against. The util-broker.c module shows how to create a unix-listener socket and pass it to a new instance of dbus-broker. It also shows how to do that with the reference implementation dbus-daemon.

Also note that at-spi2 (GNOME accessibility) does something similar and spawns its own dbus-broker instance.

There is no need to use dbus-broker-launch if service activation is not desired. Furthermore, if activation is desired, you can use dbus-broker-launch as example how to design a launcher for dbus-broker.

Lastly, you can always stick to dbus-daemon to get a well-maintained solution that does not require systemd.

[pharcosyle]

Thanks so much, this is good info. I realize as I work on this more I really need to understand DBus and its role in Guix better. This is slower-going than I'd hoped so I'm putting it on the backburner for now, but thank you again!

[nmeum]

Hey, perhaps a bit off-topic, but I am also interested in making it easier to run and use dbus-broker on Guix and Alpine (both systems without systemd). Let me know if you come up with a good Guix (home) service for dbus-broker 🙋

[pharcosyle]

I'll make you a deal: I'll furnish the Guix packages for it and you make the service. Here, I'll do my part now:
dbus-broker-guix.patch.txt

[mid-kid]

Glad to read that there's still interest in making new software not hard-depend on systemd where it doesn't need to. I'm personally interested in making it work with OpenRC, as I wanted to implement some form of dbus activation in it (instead of letting them run unsupervised). Is there any specific reason why dbus activation is frowned upon in Guix?

[pharcosyle]

Is there any specific reason why dbus activation is frowned upon in Guix?

It's not. However GNU Shepherd, Guix's service manager / init system, is deeply programmable and really nice and I'd prefer to run all the services on my machine through it rather than automagically with dbus activation.