Short piece of code to return an array of DiskInfo tuple consisting of disk’s format , driver type and source file etc. The DiskInfo tuple is a user defined tuple to allow easy access to all info about a disk device.
import libvirt
import sys
from xml.etree import ElementTree
from xml.dom import minidom
from collections import namedtuple
DiskInfo = namedtuple('DiskInfo', ['device', 'source_file', 'format'])
#Return a list of block devices used by the domain
def get_target_devices(dom):
#Create a XML tree from the domain XML description.
tree=ElementTree.fromstring(dom.XMLDesc(0))
#The list of block device names.
devices=[]
#Iterate through all disk of the domain.
for target in tree.findall("devices/disk"):
#Within each disk found, get the source file
#for ex. /var/lib/libvirt/images/vmdisk01.qcow2
for src in target.findall("source"):
file=src.get("file")
#The driver type: For ex: qcow2/raw
for src in target.findall("driver"):
type=src.get("type")
#Target device like: vda/vdb etc.
for src in target.findall("target"):
dev=src.get("dev")
#Make them all into a tuple
Disk = DiskInfo(dev, file, type)
#Check if we have already found the device name for this domain.
if not Disk in devices:
devices.append(Disk)
#Completed device name list.
return devices
Here dom is the dom returned after call to conn.lookupByName or equivalent function.
Calling function was:
for dev in get_target_devices(dom):
print( "Processing Disk: %s",dev)