[libvirt] [PATCH libvirt-java 8/9] Implement and use virDomainMigrateToURI2 instead of virDomainMigrateToURI

[Wido den Hollander]

On 01/08/2013 09:18 AM, Claudio Bley wrote:
> At Mon, 07 Jan 2013 17:10:16 -0700,
> Eric Blake wrote:
>>
>> On 01/05/2013 04:48 AM, Wido den Hollander wrote:
>>> The migrateToURI method now uses virDomainMigrateToURI2 so we can support
>>> some more features.
>>>
>>
>>> +    public int migrateToURI(String dconnuri, String miguri, String dxml, long flags, String dname, long bandwidth) throws LibvirtException {
>>> +        int returnValue = libvirt.virDomainMigrateToURI2(VDP, dconnuri, miguri, dxml, new NativeLong(flags), dname, new NativeLong(bandwidth));
>>> +        processError();
>>> +        return returnValue;
>>> +    }
>>> +
>>
>>>        */
>>>       public int migrateToURI(String uri, long flags, String dname, long bandwidth) throws LibvirtException {
>>> -        int returnValue = libvirt.virDomainMigrateToURI(VDP, uri, new NativeLong(flags), dname, new NativeLong(bandwidth));
>>> -        processError();
>>> -        return returnValue;
>>> +        return migrateToURI(uri, null, null, flags, dname, bandwidth);
>>>       }
>>
>> When you make changes like this, you need to worry about back-compat
>> issues.  Remember, older versions of libvirt did not have
>> virDomainMigreateToURI2, so you may be effectively turning the old
>> migrateToURI(4-args) into a call to a new API, which will break when
>> targetting older libvirt, whereas if you kept it as a call to the older
>> libvirt.virDomainMigrateToURI, the older libvirt can still do the
>> migration.
>
> I already checked this. (Wido, it would have been nice if you said
> when this libvirt function came into existence, so review would have
> been easier.)
>

Sorry for that. Thanks for all the feedback you gave, I'll work on a new 
set of patches which addresses all these points.

> Currently, libvirt 0.9.12 is required by libvirt-java evidenced by
> this line in build.properties:
>
> libvirt.required=0.9.12
>
> virDomainMigreateToURI2 was introduced in libvirt 0.9.2.
>
>> There may be more patches like this in your series, but in
>> general, you should favor forwarding calls to the older API, not the
>> newer API, so that the clients will work against as many libvirt
>> versions as possible.
>
> OK, this makes sense. But where do we draw the line?
>

Indeed. I looked the same up and thought that it should work due to that 
requirement.

Wido

> Claudio
>