[Libvir] RFC: get/set properties

[Ryan Scott]

Henri Cook wrote:
> My first thought as a layman is that libvirt should only contain
> information related to the actual running of the virtual machine i.e.
> not things that might concern say, customer data (this may not be your
> use case).
> 
> I would say that's up to the end user to manage with their own
> databases, cross referenced with a virtual machine name or similar
> unique identifier.

The end users are free to do that, but this presents a simplified 
administration model.  Why create a separate database, when the 
information we need can be stored in the domain description?

-Ryan

> 
> I'd be interested to hear what those who've actually contributed to the
> project think though! :p
> 
> Henri
> 
> Ryan Scott wrote:
>>   I'd like to get some comments on the following...
>>
>>   We would like to use libvirt to store some properties related to a
>> domain.  This can be done by adding a simple get/set API as follows:
>>
>> /*
>>  * Domain property get/set interfaces
>>  *
>>  * For GetProp, the return value must be freed by the caller.
>>  */
>> char *          virDomainGetProp    (virDomainPtr domain,
>>                         const char *propName);
>>
>> int         virDomainSetProp    (virDomainPtr domain,
>>                         const char *propName,
>>                         const char *value);
>>
>>
>>   Sample command-line usage:
>>
>> virsh # setprop solaris-pv-0 foo bar
>>
>> virsh # setprop solaris-pv-0 blah 3
>>
>> virsh # getprop solaris-pv-0 foo
>> foo: bar
>>
>>   The XML would look something like this:
>>
>> virsh # dumpxml solaris-pv-0
>> <domain type='xen' id='-1'>
>> [ snip ]
>>   <properties>
>>     <blah value="3"/>
>>     <foo value="bar"/>
>>   </properties>
>> </domain>
>>
>>   Looking at the Xen code, I'll need to do a bit of work on that API
>> before I can implement this.  I don't know how well this will fit into
>> the other hypervisors that Libvirt supports, so I'll leave those
>> implementations up to someone else :)
>>
>>   Any thoughts?
>>
>> -Ryan
>>
>> -- 
>> Libvir-list mailing list
>> Libvir-list at redhat.com
>> https://www.redhat.com/mailman/listinfo/libvir-list