[Engine-devel] restapi: New params for import VM/Template

[Gilad Chaplik]

Thanks, 
Gilad.

----- Original Message -----
> From: "Ori Liel" <oliel at redhat.com>
> To: "Michael Pasternak" <mpastern at redhat.com>
> Cc: "engine-devel" <engine-devel at ovirt.org>, "Itamar Heim" <iheim at redhat.com>, "Doron Fediuck" <dfediuck at redhat.com>,
> "Gilad Chaplik" <gchaplik at redhat.com>
> Sent: Wednesday, May 16, 2012 2:49:17 PM
> Subject: Re: restapi: New params for import VM/Template
> 
> >On 05/16/2012 01:16 PM, Gilad Chaplik wrote:
> >> Hi All,
> >>
> >> I am adding the ability to import a VM or a Template to a
> >> storage-domain,
> >> when this VM or Template already exists in the destination storage
> >> domain.
> >> Until now, Backend failed this. Now I want to enable the user to
> >> specify
> >> that he wishes this VM/Template will be created again by a
> >> different name,
> >> i.e - cloned.
> >>
> >> [feature page:
> >> http://www.ovirt.org/wiki/Features/ImportMoreThanOnce]
> >>
> >> I plan to achieve this using a new parameter, but I want to reach
> >> an agreement
> >> about this parameter's name. I thought simply to call it "clone".
> >>
> >> Another thing that I'll do in the patch-set is add the
> >> currently-missing ability
> >> to specify whether the snapshots of the VM, which is being
> >> imported, will
> >> be collapsed into a single snapshot (we have this ability in GUI).
> >> I am also
> >> deliberating about the name of this parameter. I thought about
> >> "collapse_snapshots" (same as in GUI).
> >>
> >> Does anyone think "clone" and "collapse_snapshots" are
> >> inappropriate and has
> >
> >/clone/ already in-use (used to clone vm from template),

clone here has a different context, clone VM vs. clone disks.

> >
> ><vm>
> >  <disks>
> >    <clone>true|false</clone>
> >...,
> >
> >you can simply say if imported vm has <name> element, this is
> >import+clone, otherwise import,
> 
> If in the future we will want to enable overriding a VM's params on
> import, this will be confusing
> (because a user might want to import a VM and change it's name - but
> not clone it if it already exists).

+1, cloning a vm and changing the vm's metadata (i.e vm's name) should not be inter-dependent.

> 
> >as about collapse_snapshots, i don't mind, but this should be done
> >in the way <clone> is implemented
> >in <disks> collection
> 
> Semantically, a snapshot is a point in time of a VM. It not only
> associated any more only with the VM's
> disks; it includes the VM's meta-data as well. For this reason, maybe
> the parameter collapse_snapshots
> should not be in <disks> collection (although, technically, the
> collapse will be done on disks)

+1, I think the collapse_snapshots should be in the vm context (snapshots is under vm).

Other than that, currently, if you want to clone a vm, it must be 'collapsed snapshots', so
the flow to clone a vm (with your suggestion) will be:

<action>
    <vm>
        <name>new_vm</..>
        <disks>
            <collapse_snapshot>true</..> 
        </..>
    </..>
    <clone>true</..>
</..>

where collapse_snapshot should be superior to clone, this structure is a bit confusing.

> 
> >
> >
> >> better suggestions?
> >>
> >> Thanks,
> >> Gilad
> >
> >
> >--
> >
> >Michael Pasternak
> >RedHat, ENG-Virtualization R&D
>