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On Wed, Feb 5, 2014 at 1:35 AM, Julien Danjou <julien at danjou.info> wrote:
> On Tue, Feb 04 2014, Joe Gordon wrote:
>
>> Ceilometer running a plugin in nova is bad (for all the reasons
>> previously discussed),
>
> Well, I partially disagree. Are you saying that nobody is allowed to run
> a plugin in Nova? So what are these plugins in the first place?
> Or if you're saying that Ceilometer cannot have plugins in Nova, I would
> like to know why.


Dan explained it well in another email.

Is the plugin run in devstack? I couldn't seem to find the code that
enables the ceilometer plugin in nova.


>
> What is wrong, I agree, is that we have to use and mock nova internals
> to test our plugins. OTOH anyone writing plugin for Nova will have the
> same issue. To which extend this is a problem with the plugin system,
> I'll let everybody thing about it. :)

Yup, the nova plugin system is not a stable API and we don't make any
guarantees about plugins working after an upgrade.  In other words
plugins will inventively break (which is why I would prefer to not use
them upstream).

>
>> So what can nova do to help this?  It sounds like you have a valid use
>> case that nova should support without requiring a plugin.
>
> We just need the possibility to run some code before an instance is
> deleted, in a synchronous manner - i.e. our code needs to be fully
> executed before Nova can actually destroyes the VM.
>
> --
> Julien Danjou
> ;; Free Software hacker ; independent consultant
> ;; http://julien.danjou.info