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Greetings,

I'd like to request a FFE for 2 features I've been working on during
Juno which, unfortunately, haven been delayed for different reasons
during this time.

The first feature is the switch-over to glance_store. Glance store, for
those not familiar with it, is a library containing the code that used
to live under `glance/store`. During Icehouse, this idea came up and I
started working on it right away. By the time of Icehouse was released,
the library was not mature enough and we (glance-core) were a bit
concerned about the risks of rushing this work. At the Juno summit, I
led a session on this library were we discussed the current status and
agreed on a path forward for this library and the other feature below.

The library contains glance's old store code with really few changes to
the API in order to make it decent enough for a library. As you can see
in the review[0], which has been around since June 17th, the amount of
code changed is small.

Once the rename of the library[1] happened, the gate tests started
passing. This is to say that the risks related to the library itself are
low.

One bit that worries me is the alignment between the current
glance_store library and the stores that still exist in glance. I
believe some patches have landed that we need to port to this new
library. However, I'm less worried about that because we can still
backport them and release a new version of the library and it'll still
be consumed by Glance - sorry if it seems I'm oversimplifying the issue.

The second feature that I'd like to get a FFE exception for is the
random access to image data. This feature was approved and agreed on for
Juno. Instead of implementing it in Glance directly, I decided -
genuinely -  to implement it on top of glance_store to avoid the
re-implementation once the library was done. Unfortunately, due to the
delays the library had, this patch got stuck in the review queue.

The feature has been in the review[2] queue since Jun 25. The feature
was implemented on top of the API v2 and users have to opt-in to access
random parts of the image data. This feature has to be backed by
glance_store and it depends on the store support for random access. I
believe the risk related to this feature is low.

Both blueprints[3][4] were discussed and agreed on, although the later
doesn't reflect so.

Cheers,
Flavio

[0] https://review.openstack.org/#/c/100636/
[1]
http://lists.openstack.org/pipermail/openstack-dev/2014-August/044203.html
[2] https://review.openstack.org/#/c/103068/
[3] https://blueprints.launchpad.net/glance/+spec/create-store-package
[4] https://blueprints.launchpad.net/glance/+spec/restartable-image-download

-- 
@flaper87
Flavio Percoco