Open Stack

Hi,

Currently working on implementing the RequestSpec object BP [1], I had 
some cool comments on my change here :
https://review.openstack.org/#/c/145528/12/nova/objects/request_spec.py,cm

Since we didn't discussed on how to persist that RequestSpec object, I 
think the comment is valuable.

For the moment, the only agreed spec for persisting the object that we 
have is [2] but there is also a corollar here that means that we would 
have to persist more than the current fields 
https://review.openstack.org/#/c/169901/3/specs/liberty/approved/add-buildrequest-obj.rst,cm

So, there are 2 possibilities :
  #1, we only persist the RequestSpec for the sole Scheduler and in that 
case, we can leave as it is - only a few fields from Instance are stored
  #2, we consider that RequestSpec can be used for more than just the 
Scheduler, and then we need to make sure that we will have all the 
instance fields then.


I'm not strongly opiniated on that, I maybe consider that #2 is probably 
the best option but there is a tie in my mind. Help me figuring out 
what's the best option.

-Sylvain

[1] : 
http://specs.openstack.org/openstack/nova-specs/specs/liberty/approved/request-spec-object.html
[2] : 
http://specs.openstack.org/openstack/nova-specs/specs/liberty/approved/persist-request-spec.html