[systemd-devel] how to get sd_notify state/variables from dbus?

[Lennart Poettering]

On Tue, 12.01.16 19:38, Mantas Mikulėnas (grawity at gmail.com) wrote:

> On Tue, Jan 12, 2016 at 7:25 PM, Lennart Poettering <lennart at poettering.net>
> wrote:
> 
> > On Fri, 08.01.16 18:09, Rick Richardson (rick.richardson at gmail.com) wrote:
> >
> > > I have a fleet of applications that need to pass some critical variables
> > > back to systemd so that our services monitor can collect them.  My hope
> > is
> > > that this can be done via sd_notify as it is very much a
> > config-management
> > > and process monitoring related task.
> > >
> > > Currently my monitor subscribes to PropertiesChanged in dbus, and gets
> > the
> > > active/running notification upon an sd_notify from the service, I can see
> > > the StatusText variable set via the STATUS=... but I can't seem to figure
> > > out where the rest of the notify state is stored.
> >
> > It currently is not.
> >
> > We could expose this data I figure, but I am not entirely sure how
> > that could even look like, as for unknown sd_notify() fields it's not
> > clear whether they are supposed to extend or replace any unrelated
> > previously set settings... i.e. if you first send X_FOO=1 and then
> > X_BAR=1 and then query the data, would you get "X_FOO=1 X_BAR=1" back,
> > or just "X_BAR=1"? The former would mean we'd might get into trouble
> > if people keep inventing new fields. The latter would mean it's
> > useless if people assume additive operation of the the data...
> >
> 
> Isn't this basically something that etcd was meant to do?

Not seeing how a distributed key store could be related to daemon
status notifications?

Lennart

-- 
Lennart Poettering, Red Hat