def validate(self):
if self.base_id not in self.chain:
raise se.VolumeIsNotInChain(self.sd_id, self.img_id, self.base_id)
if self.top_id not in self.chain:
raise se.VolumeIsNotInChain(self.sd_id, self.img_id, self.top_id)
# Validate that top volume is the parent of the base.
if self.top_vol.getParent() != self.base_id:
raise se.WrongParentVolume(self.base_id, self.top_id)
if self.base_vol.isShared():
raise se.SharedVolumeNonWritable(self.base_vol)
if self.top_vol.isShared():
raise se.SharedVolumeNonWritable(self.top_vol)
def fail():
raise se.VolumeIsNotInChain(None, None, None)
