[Engine-devel] Clone VM from snapshot feature

[Yair Zaslavsky]

On 02/27/2012 09:09 PM, Itamar Heim wrote:
> On 02/26/2012 05:05 PM, Yair Zaslavsky wrote:
>> On 02/26/2012 04:55 PM, Ayal Baron wrote:
>>>
>>>
>>> ----- Original Message -----
>>>> On 02/26/2012 04:38 PM, Ayal Baron wrote:
>>>>> Yair, what about import of VM more than once?
>>>> Hi Ayal,
>>>> We consider this as a different feature.
>>>> Gilad Chaplik is the feature owner.
>>>> I can think of some very similar features to this one (not just
>>>> import
>>>> more than once).
>>>
>>> First, I couldn't find a feature page for that.
>>> Second, I don't really understand the difference, there are subtle
>>> differences in the flow, but it is basically the same.
>>> In fact. the only difference I can think of is that it is initiated
>>> from import and not from right click on the snapshot...
>>>
>>> What other similar features will this *not* cover?
>> I can tell you that for current testing until fully integrated with
>> snapshots modifications, I am testing it on VM which is down.
>> Not sure we're interested in this, but here is an example of possible
>> feature.
> 
> I think Ayal point/question is similar to mine - why at general code
> level (obviously there are implementation differences) and user
> experience wise, the following aren't similar:
> [AddVmFromBlank]
> AddVmFromTemplate
> AddVmFromVm
> AddVmFromSnapshot
> AddVmFromImportCandidate[1]

Of course there is shared code - for example, in the class diagram I
presented for Clone VM from Snapshot, it can clearly be seen that there
is code reuse, and there are two paths of "image-creation" (actually,
there is of course also a 3rd path of 'createImage' verb) - path for
snapshot and path for copyImage - In addition, the code of the
"addVmXXXCommand" usually extends AddVmCommand, and of course introduces
some changes.
In addition , differences may occur at MLA (for example, for
clone-vm-from-snapshot, and maybe other future flows I'm considering of
adding a new action-group for CloneVm to the code - I'll update the wiki
shortly on this), and of course UI-wise.
So I hope that now I gave more explanations on where the code is similar
and where its different (actually, I would like to point that in my
changes, I'm striving to introduce more code-reuse).

Yair

> 
> 
> [1] yes, there is a difference if you select more than a single import
> candidate (adding multiple VMs), but that's actually at UI level, not
> backend implementation.
>