[libvirt] RFCv2: virDomainSnapshotCreateXML enhancements

[Stefan Hajnoczi]

On Tue, Aug 23, 2011 at 4:18 PM, Eric Blake <eblake at redhat.com> wrote:
> On 08/23/2011 09:12 AM, Stefan Hajnoczi wrote:
>> I think we simply cannot expose all this complexity to users.  Each
>> application would have to support the many different cases.  Libvirt
>> needs to tie this stuff together and present an interface that
>> applications can use without worrying how to actually get at the
>> snapshot data.
>
> I don't see any problem with exposing the lower layers as a start, then
> adding higher layers as we go.  There are different classes of users, and
> both layers are useful in the right context.  But at the same time, I agree
> with you that what I have done so far is just a start, and by no means the
> end of snapshot-related libvirt work.

Do you have a user in mind who will be able to use this API?  The
kinds of apps I am thinking about cannot make use of this API.

This is largely because there is no API for accessing snapshot
contents.  But even the snapshot API itself has too many flags/cases
that require the user to already know exactly what they want to do
down to a level of detail where I wonder why they would even want to
use libvirt and not just do, say, LVM snapshots manually.

Perhaps I'm missing what adding this API enables.  Please share what
use case you have in mind.

Stefan