-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I think you meant to include the list.
The idea is that *when* the charm for A connects to B, it changes the configuration that C depends on. So *C* should then see some form of "config-changed" hook get fired. John =:-> On 2014-01-30 14:51, Sameer Zeidat wrote: >> So when A is connected to B it sets a value in its relation with >> C > that C then reacts to. > > If I understood juju correctly, once A and C are joined there's no > way for C to react to any change in A's relations to other charms. > There's no 'relation-peerconfig-changed' hook for instance that > gets invoked in C when A joins/departs B. > > Sorry for not providing a specific example. > > Regards, > ------------------------------------------------------------------------ > > From: John Arbash Meinel <mailto:[email protected]> > Sent: 30/01/2014 7:30 PM To: Sameer Zeidat > <mailto:[email protected]>; Juju email list > <mailto:[email protected]> Subject: Re: Relation dependency > > On 2014-01-30 5:49, Sameer Zeidat wrote: >> Hello, > >> I'm relatively new to juju, and starting to write some charms. > >> One thing I'm missing is relation dependency. Say service A can >> join a relation with B and C. I would like for juju to stop A >> from joining C if it has not joined B first. Same also, stop A >> from departing C if it hasn't departed B first. > > I'm pretty sure most of this is taken care of in terms of charm > configuration. So if charm A sees C but doesn't yet see B, then it > doesn't configure its connection to C. This is outside of what > Juju specifically controls. > > >> If this isn't possible then I'd like to at least be able to run >> a hook on C, for instance, if A's relation with B changes. > > Generally this is done by reflecting some sort of configuration > change that C can see. So when A is connected to B it sets a value > in its relation with C that C then reacts to. > > >> Does it make sense? > >> Thanks, > > > > Having specific examples can help set the tone for what is > actually being accomplished and how it would be modeled with Juju's > relations. > > John =:-> > -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.13 (Cygwin) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iEYEARECAAYFAlLqL2kACgkQJdeBCYSNAAOFEwCeJk9aJo3R37lNxjmIHivWPWiR eagAn19YwEiuI6Fn2wiRMBoy3Pc0hPBY =aDko -----END PGP SIGNATURE----- -- Juju-dev mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/juju-dev
