On Fri, Apr 09, 2010 at 10:12:57AM -0400, Hugh O. Brock wrote: > On Fri, Apr 09, 2010 at 09:49:51AM +0200, Daniel Veillard wrote: > > On Thu, Apr 08, 2010 at 11:27:46PM +0100, Antoine Martin wrote: > > > Hi, > > > > > > I am moving this thread here as this seems more appropriate. > > > Sorry it has taken so long.. > > > > > > Here are 2 things that really get in the way of moving my existing > > > installations to libvirt: > > > * I tend to store much meta data with each VM instance: it can be things > > > like ownership (contact details as text), monitoring info (sms phone > > > numbers), backup (list of paths), firewall rules (custom syntax, with > > > failover rules, etc), etc. > > > At the moment, these extra bits of information consist of just a few > > > optional lines of shell in each VM's definition file. I can extend these > > > whenever I need, enumerate the VMs using the standard mechanism and > > > trigger my specific actions as needed (firewall rules, backup or whatever). > > > I see no way of doing this with libvirt. But please correct me if I am > > > wrong. > > > > One of the things I'm gonna do post 0.8.0 is allow to bundle comments > > and elements from a foreign namespace in the libvirt XML definition. > > > > Currently libvirt will happilly consume such a definition but all the > > extra are lost, basically at parse time we just extract the informations > > we know about, and everything else is lost. I want to provide clean ways > > to add metadata coming from the user and preserve them. I will probably > > limit the places where such metadata will be allowed: > > > > 1/ to avoid the full complexity of an XML structured editor within > > libvirt > > 2/ to not have to completely modify our configuration reading and > > saving code, but add this as an extra layer > > 3/ to be able to modify the Relax-NG schemas in a reasonnable way > > to allow those elements from foreign namespaces > > > > It's not a piece of cake, there will have to be some limitation and > > heuristics to avoid the extreme complexity and changes that a full tree > > preservation system would requires, but I think that should be > > sufficient for your kind of use case, > > Daniel, this kind of thing would allow (for example) the addition of > information to the domain XML that could be used by an event hook > script? I guess by the script getting the domain XML and fishing out > the extra metadata bits? The hook is given the full XML document associated with the guest. Thus if we add support for parsing & preserving extra namespaced elements in the XML, this data would be available to the hooks. The key is that the data must roundtrip XML -> parsed format -> XML. Currently you can pas extra data in, but it just gets ignored, so not roundtripped Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://deltacloud.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :| -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list