Unraid USB Device Auto Attach Tool - Create usbdevices.cfg in the same folder containing the device names one per line

usbattach.py

#!/usr/bin/python
# Unraid USB Device Auto Attach Tool, Made By SebbiUltimate 2020
import sys
import os
import re
import subprocess
import xml.etree.ElementTree as ET

def getDeviceCfg():
	with open(os.path.abspath(os.path.dirname(sys.argv[0]))+'/usbdevices.cfg') as f:
		cfg=[]
		for line in f:
			cfg.append([elt.strip() for elt in line.split(';')])
	return cfg

def getVMDevices(vmname):
	xmlfile="/tmp/vmdevices_"+vmname+".xml"
	os.system("virsh dumpxml "+vmname+" > "+xmlfile)
	VXMLP = VirshXMLParser(xmlfile)
	usbdevs = VXMLP.get_elements(path='./devices/', tag='hostdev', attrib='type', value='usb', listout=True)
	DevVXMLP = VirshXMLParser()
	vmdevs=[]
	for usbdev in usbdevs:
		DevVXMLP.root = usbdev
		address = DevVXMLP.get_elements(path='./source/', tag='address')
		vmdev={'bus': address.get('bus'), 'device': address.get('device')}
		vmdevs.append(vmdev)
	return vmdevs

def getHostDevices():
	device_re = re.compile("Bus\s+(?P<bus>\d+)\s+Device\s+(?P<device>\d+).+ID\s(?P<id>\w+:\w+)\s(?P<tag>.+)$", re.I)
	df = subprocess.check_output("lsusb")
	devices = []
	for i in df.split('\n'):
		if i:
			info = device_re.match(i)
			if info:
				dinfo = info.groupdict()
				#dinfo['device'] = '/dev/bus/usb/%s/%s' % (dinfo.pop('bus'), dinfo.pop('device'))
				dinfo['bus']=str(int(dinfo['bus']))
				dinfo['device']=str(int(dinfo['device']))
				dinfo['tag']=dinfo['tag'].strip()
				devices.append(dinfo)
	return devices

def getRunningVMs():
	vl = subprocess.check_output(["virsh", "list"])
	vms=[]
	for line in vl.split('\n')[2:]:
		if line:
			vms.append(line.split()[1])
	return vms

def writeDevXML(bus,device):
	devxml="<hostdev mode='subsystem' type='usb'><source><address bus='"+bus+"' device='"+device+"'/></source></hostdev>"
	path="/tmp/usbdev_"+bus+"-"+device+".xml"
	f = open(path, "w")
	f.write(devxml)
	f.close()
	return path

def attachDevice(VM,bus,device):
	path=writeDevXML(bus,device)
	print(subprocess.check_output(["virsh", "attach-device",VM,path]))
	
def detachDevice(VM,bus,device):
	path=writeDevXML(bus,device)
	print(subprocess.check_output(["virsh", "detach-device",VM,path]))
	
class VirshXMLParser:

	def __init__(self, xmlfile=None):
		self.root = None
		if xmlfile:
			tree = ET.parse(xmlfile)
			self.root = tree.getroot()

	def get_attrib(self, attr, **args):
		element = self.get_elements(**args)
		if element is None:
			return 'None'
		else:
			return element.get(attr)

	def get_elements(
			self,
			path=None,
			tag=None,
			attrib=None,
			value=None,
			ns={},
			listout=False):
		elements = [self.root]
		search = '.' if not path else path
		if tag:
			search = search + tag
		if attrib and value:
			search = "%s[@%s='%s']" % (search, attrib, value)
		elements = self.root.findall(search, ns)
		if listout:
			return elements
		if elements:
			return elements[0]
		return None

	def get_text(self, **args):
		element = self.get_elements(**args)
		if element is None:
			return 'None'
		else:
			return element.text


print("**Unraid USB Device Auto Attach Tool**")
hostdevs=getHostDevices()

attachList=[]
detachList=[]

i=0
for VM in getRunningVMs():
	print("Processing VM "+VM)
	vmdevlist=[]
	for dns in getDeviceCfg():
		for dn in dns:
			devnum=next((i for i, item in enumerate(hostdevs) if item["tag"] == dn), None)
			if devnum:
				dev=hostdevs.pop(devnum)
				vmdevlist.append(dev)
				break
	vmdevices=getVMDevices(VM)
	shoulddevices=vmdevlist
	for d in shoulddevices:
		del d['tag']
		del d['id']
	if (cmp(vmdevices,shoulddevices)):
		print("Devices of "+VM+" are not matching the configured Device List, reattaching...")
		for dev in vmdevices:
			print("Adding USB device "+dev['bus']+"-"+dev['device']+" from "+VM+" to detach list.")
			dev['VM']=VM
			detachList.append(dev)
		for dev in shoulddevices:
			print("Adding USB device "+dev['bus']+"-"+dev['device']+" from "+VM+" to attach list.")
			dev['VM']=VM
			attachList.append(dev)
	else:
		print("Devices of "+VM+" are OK")
	i+=1

for dev in detachList:
	print("Detaching USB device "+dev['bus']+"-"+dev['device']+" from "+VM)
	detachDevice(dev['VM'],dev['bus'],dev['device'])
	
for dev in attachList:
	print("Attaching USB device "+dev['bus']+"-"+dev['device']+" to "+VM)
	attachDevice(dev['VM'],dev['bus'],dev['device'])

print("Finished.")