[systemd-devel] dbus API for unit state change?

[Mantas Mikulėnas]

On Thu, Oct 3, 2013 at 5:27 AM, Brandon Philips <brandon at ifup.co> wrote:
> Hello-
>
> While writing against the dbus bindings I found one missing feature:
> signals from org.freedesktop.systemd1.Manager on unit "ActiveState"
> changes.
>
> I can do this today by polling ListUnits but I would rather not have
> my process doing this.
>
> There are two possible APIs:
>
> 1. Distinct signal per type
>
> UnitActive()
> UnitInactive()
> UnitReloading()
> UnitFailed()
> UnitActivating()
> UnitDeactivating()
>
> 2. One signal type for all changes:
>
> UnitActiveStateChanged()
>
> This would encode the ActiveState and SubState in that signals
> properties. That seems a much simpler.
>
> Before writing the patch I wanted to get some feedback on the API and
> make sure this hadn't been implemented for some other reason either.

This is already handled by the PropertiesChanged signal in the
standard org.freedesktop.DBus.Properties interface. (Although systemd
only sends invalidated_properties and the new values have to be
retrieved manually, so that's not really perfect yet.)

-- 
Mantas Mikulėnas <grawity at gmail.com>