pvc/client-common/common.py

439 lines
14 KiB
Python

#!/usr/bin/env python3
# common.py - PVC client function library, common fuctions
# Part of the Parallel Virtual Cluster (PVC) system
#
# Copyright (C) 2018-2019 Joshua M. Boniface <joshua@boniface.me>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
#
###############################################################################
import uuid
import lxml
import math
import kazoo.client
import client_lib.zkhandler as zkhandler
###############################################################################
# Supplemental functions
###############################################################################
#
# Validate a UUID
#
def validateUUID(dom_uuid):
try:
uuid.UUID(dom_uuid)
return True
except:
return False
#
# Connect and disconnect from Zookeeper
#
def startZKConnection(zk_host):
zk_conn = kazoo.client.KazooClient(hosts=zk_host)
try:
zk_conn.start()
except kazoo.handlers.threading.KazooTimeoutError:
print('Timed out connecting to Zookeeper at "{}".'.format(zk_host))
exit(1)
except Exception as e:
print('Failed to connect to Zookeeper at "{}": {}'.format(zk_host, e))
exit(1)
return zk_conn
def stopZKConnection(zk_conn):
zk_conn.stop()
zk_conn.close()
return 0
#
# Parse a Domain XML object
#
def getDomainXML(zk_conn, dom_uuid):
try:
xml = zkhandler.readdata(zk_conn, '/domains/{}/xml'.format(dom_uuid))
except:
return None
# Parse XML using lxml.objectify
parsed_xml = lxml.objectify.fromstring(xml)
return parsed_xml
#
# Get the main details for a VM object from XML
#
def getDomainMainDetails(parsed_xml):
# Get the information we want from it
duuid = str(parsed_xml.uuid)
try:
ddescription = str(parsed_xml.description)
except AttributeError:
ddescription = "N/A"
dname = str(parsed_xml.name)
dmemory = str(parsed_xml.memory)
dmemory_unit = str(parsed_xml.memory.attrib['unit'])
if dmemory_unit == 'KiB':
dmemory = int(int(dmemory) / 1024)
elif dmemory_unit == 'GiB':
dmemory = int(int(dmemory) * 1024)
dvcpu = str(parsed_xml.vcpu)
try:
dvcputopo = '{}/{}/{}'.format(parsed_xml.cpu.topology.attrib['sockets'], parsed_xml.cpu.topology.attrib['cores'], parsed_xml.cpu.topology.attrib['threads'])
except:
dvcputopo = 'N/A'
return duuid, dname, ddescription, dmemory, dvcpu, dvcputopo
#
# Get long-format details
#
def getDomainExtraDetails(parsed_xml):
dtype = str(parsed_xml.os.type)
darch = str(parsed_xml.os.type.attrib['arch'])
dmachine = str(parsed_xml.os.type.attrib['machine'])
dconsole = str(parsed_xml.devices.console.attrib['type'])
demulator = str(parsed_xml.devices.emulator)
return dtype, darch, dmachine, dconsole, demulator
#
# Get CPU features
#
def getDomainCPUFeatures(parsed_xml):
dfeatures = []
for feature in parsed_xml.features.getchildren():
dfeatures.append(feature.tag)
return dfeatures
#
# Get disk devices
#
def getDomainDisks(parsed_xml):
ddisks = []
for device in parsed_xml.devices.getchildren():
if device.tag == 'disk':
disk_attrib = device.source.attrib
disk_target = device.target.attrib
disk_type = device.attrib['type']
if disk_type == 'network':
disk_obj = { 'type': disk_attrib.get('protocol'), 'name': disk_attrib.get('name'), 'dev': disk_target.get('dev'), 'bus': disk_target.get('bus') }
elif disk_type == 'file':
disk_obj = { 'type': 'file', 'name': disk_attrib.get('file'), 'dev': disk_target.get('dev'), 'bus': disk_target.get('bus') }
else:
disk_obj = {}
ddisks.append(disk_obj)
return ddisks
#
# Get a list of disk devices
#
def getDomainDiskList(zk_conn, dom_uuid):
domain_information = getInformationFromXML(zk_conn, dom_uuid)
disk_list = []
for disk in domain_information['disks']:
disk_list.append(disk['name'])
return disk_list
#
# Get domain information from XML
#
def getInformationFromXML(zk_conn, uuid):
"""
Gather information about a VM from the Libvirt XML configuration in the Zookeper database
and return a dict() containing it.
"""
domain_state = zkhandler.readdata(zk_conn, '/domains/{}/state'.format(uuid))
domain_node = zkhandler.readdata(zk_conn, '/domains/{}/node'.format(uuid))
domain_lastnode = zkhandler.readdata(zk_conn, '/domains/{}/lastnode'.format(uuid))
domain_failedreason = zkhandler.readdata(zk_conn, '/domains/{}/failedreason'.format(uuid))
try:
domain_node_limit = zkhandler.readdata(zk_conn, '/domains/{}/node_limit'.format(uuid))
domain_node_selector = zkhandler.readdata(zk_conn, '/domains/{}/node_selector'.format(uuid))
domain_node_autostart = zkhandler.readdata(zk_conn, '/domains/{}/node_autostart'.format(uuid))
except:
domain_node_limit = None
domain_node_selector = None
domain_node_autostart = None
if not domain_node_limit:
domain_node_limit = 'False'
parsed_xml = getDomainXML(zk_conn, uuid)
domain_uuid, domain_name, domain_description, domain_memory, domain_vcpu, domain_vcputopo = getDomainMainDetails(parsed_xml)
domain_networks = getDomainNetworks(parsed_xml)
domain_type, domain_arch, domain_machine, domain_console, domain_emulator = getDomainExtraDetails(parsed_xml)
domain_features = getDomainCPUFeatures(parsed_xml)
domain_disks = getDomainDisks(parsed_xml)
domain_controllers = getDomainControllers(parsed_xml)
if domain_lastnode:
domain_migrated = 'from {}'.format(domain_lastnode)
else:
domain_migrated = 'no'
domain_information = {
'name': domain_name,
'uuid': domain_uuid,
'state': domain_state,
'node': domain_node,
'last_node': domain_lastnode,
'migrated': domain_migrated,
'failed_reason': domain_failedreason,
'node_limit': domain_node_limit,
'node_selector': domain_node_selector,
'node_autostart': domain_node_autostart,
'description': domain_description,
'memory': domain_memory,
'vcpu': domain_vcpu,
'vcpu_topology': domain_vcputopo,
'networks': domain_networks,
'type': domain_type,
'arch': domain_arch,
'machine': domain_machine,
'console': domain_console,
'emulator': domain_emulator,
'features': domain_features,
'disks': domain_disks,
'controllers': domain_controllers,
'xml': lxml.etree.tostring(parsed_xml, encoding='ascii', method='xml').decode().replace('\"', '\'')
}
return domain_information
#
# Get network devices
#
def getDomainNetworks(parsed_xml):
dnets = []
for device in parsed_xml.devices.getchildren():
if device.tag == 'interface':
net_type = device.attrib['type']
net_mac = device.mac.attrib['address']
net_bridge = device.source.attrib[net_type]
net_model = device.model.attrib['type']
net_obj = { 'type': net_type, 'mac': net_mac, 'source': net_bridge, 'model': net_model }
dnets.append(net_obj)
return dnets
#
# Get controller devices
#
def getDomainControllers(parsed_xml):
dcontrollers = []
for device in parsed_xml.devices.getchildren():
if device.tag == 'controller':
controller_type = device.attrib['type']
try:
controller_model = device.attrib['model']
except KeyError:
controller_model = 'none'
controller_obj = { 'type': controller_type, 'model': controller_model }
dcontrollers.append(controller_obj)
return dcontrollers
#
# Verify node is valid in cluster
#
def verifyNode(zk_conn, node):
if zkhandler.exists(zk_conn, '/nodes/{}'.format(node)):
return True
else:
return False
#
# Get the primary coordinator node
#
def getPrimaryNode(zk_conn):
failcount = 0
while True:
try:
primary_node = zkhandler.readdata(zk_conn, '/primary_node')
except:
primary_node == 'none'
if primary_node == 'none':
raise
time.sleep(1)
failcount += 1
continue
else:
break
if failcount > 2:
return None
return primary_node
#
# Find a migration target
#
def findTargetNode(zk_conn, dom_uuid):
# Determine VM node limits; set config value if read fails
try:
node_limit = zkhandler.readdata(zk_conn, '/domains/{}/node_limit'.format(dom_uuid)).split(',')
if not any(node_limit):
node_limit = None
except:
node_limit = None
# Determine VM search field or use default; set config value if read fails
try:
search_field = zkhandler.readdata(zk_conn, '/domains/{}/node_selector'.format(dom_uuid))
except:
search_field = 'mem'
# Execute the search
if search_field == 'mem':
return findTargetNodeMem(zk_conn, node_limit, dom_uuid)
if search_field == 'load':
return findTargetNodeLoad(zk_conn, node_limit, dom_uuid)
if search_field == 'vcpus':
return findTargetNodeVCPUs(zk_conn, node_limit, dom_uuid)
if search_field == 'vms':
return findTargetNodeVMs(zk_conn, node_limit, dom_uuid)
# Nothing was found
return None
# Get the list of valid target nodes
def getNodes(zk_conn, node_limit, dom_uuid):
valid_node_list = []
full_node_list = zkhandler.listchildren(zk_conn, '/nodes')
current_node = zkhandler.readdata(zk_conn, '/domains/{}/node'.format(dom_uuid))
for node in full_node_list:
if node_limit and node not in node_limit:
continue
daemon_state = zkhandler.readdata(zk_conn, '/nodes/{}/daemonstate'.format(node))
domain_state = zkhandler.readdata(zk_conn, '/nodes/{}/domainstate'.format(node))
if node == current_node:
continue
if daemon_state != 'run' or domain_state != 'ready':
continue
valid_node_list.append(node)
return valid_node_list
# via free memory (relative to allocated memory)
def findTargetNodeMem(zk_conn, node_limit, dom_uuid):
most_allocfree = 0
target_node = None
node_list = getNodes(zk_conn, node_limit, dom_uuid)
for node in node_list:
memalloc = int(zkhandler.readdata(zk_conn, '/nodes/{}/memalloc'.format(node)))
memused = int(zkhandler.readdata(zk_conn, '/nodes/{}/memused'.format(node)))
memfree = int(zkhandler.readdata(zk_conn, '/nodes/{}/memfree'.format(node)))
memtotal = memused + memfree
allocfree = memtotal - memalloc
if allocfree > most_allocfree:
most_allocfree = allocfree
target_node = node
return target_node
# via load average
def findTargetNodeLoad(zk_conn, node_limit, dom_uuid):
least_load = 9999
target_node = None
node_list = getNodes(zk_conn, node_limit, dom_uuid)
for node in node_list:
load = int(zkhandler.readdata(zk_conn, '/nodes/{}/load'.format(node)))
if load < least_load:
least_load = load
target_hypevisor = node
return target_node
# via total vCPUs
def findTargetNodeVCPUs(zk_conn, node_limit, dom_uuid):
least_vcpus = 9999
target_node = None
node_list = getNodes(zk_conn, node_limit, dom_uuid)
for node in node_list:
vcpus = int(zkhandler.readdata(zk_conn, '/nodes/{}/vcpualloc'.format(node)))
if vcpus < least_vcpus:
least_vcpus = vcpus
target_node = node
return target_node
# via total VMs
def findTargetNodeVMs(zk_conn, node_limit, dom_uuid):
least_vms = 9999
target_node = None
node_list = getNodes(zk_conn, node_limit, dom_uuid)
for node in node_list:
vms = int(zkhandler.readdata(zk_conn, '/nodes/{}/domainscount'.format(node)))
if vms < least_vms:
least_vms = vms
target_node = node
return target_node
# Connect to the primary host and run a command
def runRemoteCommand(node, command, become=False):
import paramiko
import hashlib
import dns.resolver
import dns.flags
# Support doing SSHFP checks
class DnssecPolicy(paramiko.client.MissingHostKeyPolicy):
def missing_host_key(self, client, hostname, key):
sshfp_expect = hashlib.sha1(key.asbytes()).hexdigest()
ans = dns.resolver.query(hostname, 'SSHFP')
if not ans.response.flags & dns.flags.DO:
raise AssertionError('Answer is not DNSSEC signed')
for answer in ans.response.answer:
for item in answer.items:
if sshfp_expect in item.to_text():
client._log(paramiko.common.DEBUG, 'Found {} in SSHFP for host {}'.format(key.get_name(), hostname))
return
raise AssertionError('SSHFP not published in DNS')
if become:
command = 'sudo ' + command
ssh_client = paramiko.client.SSHClient()
ssh_client.load_system_host_keys()
ssh_client.set_missing_host_key_policy(DnssecPolicy())
#ssh_client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh_client.connect(node)
stdin, stdout, stderr = ssh_client.exec_command(command)
return stdout.read().decode('ascii').rstrip(), stderr.read().decode('ascii').rstrip()