[ovirt-devel] Issues with the VM display type value(s)

[Einav Cohen]

Hi, 

This is about the changes introduced by patch 
http://gerrit.ovirt.org/#/c/35281 (restapi: adjust api to new 
graphics representation). 

There are a couple of issues with the VM's display type value:

(1) the "display -> type" value of the VM in the REST API seem to 
map to different properties based on the VM status. 
see http://i.imgur.com/Mn1RITW.png: 
When the VM is Up, the "display -> type" value in the REST API 
matches the 'Display' value in the GUI. 
But when the VM is Down, the "display -> type" value in the REST 
API matches the 'Graphics Protocol' value in the GUI and does not 
necessarily match the 'Display' value (e.g. in case we invoked 
'Run Once' on the VM with a different Console value). 

Is there a reason for the values in the REST API to not match the 
ones in the GUI? it's a bit confusing. 
Maybe need to have two properties in the REST API to match the two 
displayed values in the GUI: 'Display' (which, IIUC, is the 'run-
time' value) and 'Graphics Protocol' (which, IIUC, is the 
'configured'/persisted value)? 
I understand that there may be backward-compatibility issues with 
naming/terminology, but perhaps we can come up with a solution that 
will not break the backward compatibility?

(2) in patch http://gerrit.ovirt.org/#/c/35281, it seems that the 
REST API is calling a query *per VM* in order to re-populate the 
display-related values. 
This will potentially overload the engine, especially if we are 
planning to move the GUI to work over the REST API and request 
VMs every 5 seconds (by default) per client, as we are doing today. 

Are there any plans to optimize this behavior (e.g. populate the 
correct display-related values on the db-side, rather than re-
populating them on the REST-API side using a per-VM query)?

Many thanks in advance. 

----
Regards, 
Einav