API mismatch between VolumeManager and driver

[Nachi Ueno]

There are some mismatch between volume driver and the Volume manager.

- Volume manger checks return value of self.driver.create_volume_from_snapshot, however no volume driver returns value.
http://paste.openstack.org/show/2677/

- nova.volume.api didn't check snapshot_id and size. They are checked, or a default value set in driver module.
nova.volume.api should check input parameters.

[Hengqing Hu (hudayou)]

I think this is not really a bug, model_update will be none when no function return and db will not be updated.

[RonenKat (ronenkat)]

1st Item in bug report is not a bug - the manager allow the driver not to return model_update (be none), and disregards if so.

2nd, Size is checked by the low-level driver and gets a default if not valid. snapshot_id is used to get snapshot info from the DB. So an invalid value here would result in an exception on the snapshot in the volume manager code.

I don't see what extra validations should be done.

[RonenKat (ronenkat)]

1st Item in bug report is not a bug - the manager allow the driver not to return model_update (be none), and disregards if so.

2nd, Size is checked by the low-level driver and gets a default if not valid. snapshot_id is used to get snapshot info from the DB. So an invalid value here would result in an exception on the snapshot in the volume manager code.

I don't see what extra validations should be done.