Open Stack

Hello,

As we know, nova have different compute drivers with different 
limitations, you can see in this link,

https://wiki.openstack.org/wiki/HypervisorSupportMatrix

but the api doesn't reflect that, which means when the user performs 
some operations via APIs, user can not get well defined message of the 
limitations, most likely just get error status. I am thinking this 
problem for a while and feeling a limitation filter might be needed in 
current api design to filter those limitations and directly return well 
defined message, I apologize if this problem has been already discussed 
but I missed it, looking forward to your comments.

Best Regards

guohliu