[libvirt] Redesigning Libvirt: Better supporting non-hypervisor agnostic concepts

[Michal Privoznik]

On 11/15/2017 06:57 PM, Richard W.M. Jones wrote:
> On Tue, Nov 14, 2017 at 05:25:03PM +0000, Daniel P. Berrange wrote:
>> I would anticipate a standalone process "libvirt-qemu" that an
>> application can spawn, providing a normal domain XML file via the
>> command line or stdin. It would then connect to libvirtd to register
>> its existance and claim its ownership of the guest name +
>> UUID. Assuming that succeeds, 'libvirt-qemu' would directly spawn
>> QEMU.
> 
> To be really clear about this, the application would run something
> like:
> 
>   libvirt_xml = sprintf ("<domain><uuid>%s</uuid> etc etc", uuid);
>   libvirt_xml_file = /* write libvirt_xml to a temporary file */;
> 
>   if (fork () == 0) {
>     execlp ("libvirt-qemu",
>             "libvirt-qemu", "--config", libvirt_xml_file, NULL);

Problem with this is libvirt-qemu binary would need a connection object
so that ...

>   }
> 
>   dom = virDomainLookupByUUID (conn, uuid);

... it registers the domain under @conn connection (= it needs to
register the domain at the right libvirtd [or whomever is going to keep
list of running domains]).

Michal