pvc/daemon-common/common.py
Joshua M. Boniface 1b6613c280 Add live VNC information to domain output
Sets in the node daemon, returns via the API, and shows in the CLI,
information about the live VNC listen address and port for VNC-enabled
VMs.

Closes #115
2020-12-20 16:00:55 -05:00

602 lines
19 KiB
Python

#!/usr/bin/env python3
# common.py - PVC client function library, common fuctions
# Part of the Parallel Virtual Cluster (PVC) system
#
# Copyright (C) 2018-2020 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 time
import uuid
import lxml
import shlex
import subprocess
import kazoo.client
from json import loads
from re import match as re_match
from distutils.util import strtobool
import daemon_lib.zkhandler as zkhandler
###############################################################################
# Supplemental functions
###############################################################################
#
# Run a local OS command via shell
#
def run_os_command(command_string, background=False, environment=None, timeout=None, shell=False):
command = shlex.split(command_string)
try:
command_output = subprocess.run(
command,
shell=shell,
env=environment,
timeout=timeout,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
)
retcode = command_output.returncode
except subprocess.TimeoutExpired:
retcode = 128
try:
stdout = command_output.stdout.decode('ascii')
except Exception:
stdout = ''
try:
stderr = command_output.stderr.decode('ascii')
except Exception:
stderr = ''
return retcode, stdout, stderr
#
# Validate a UUID
#
def validateUUID(dom_uuid):
try:
uuid.UUID(dom_uuid)
return True
except Exception:
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 Exception:
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.get('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.get('sockets'), parsed_xml.cpu.topology.attrib.get('cores'), parsed_xml.cpu.topology.attrib.get('threads'))
except Exception:
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 = []
try:
for feature in parsed_xml.features.getchildren():
dfeatures.append(feature.tag)
except Exception:
pass
return dfeatures
#
# Get disk devices
#
def getDomainDisks(parsed_xml, stats_data):
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.get('type')
disk_stats_list = [x for x in stats_data.get('disk_stats', []) if x.get('name') == disk_attrib.get('name')]
try:
disk_stats = disk_stats_list[0]
except Exception:
disk_stats = {}
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'),
'rd_req': disk_stats.get('rd_req', 0),
'rd_bytes': disk_stats.get('rd_bytes', 0),
'wr_req': disk_stats.get('wr_req', 0),
'wr_bytes': disk_stats.get('wr_bytes', 0)
}
elif disk_type == 'file':
disk_obj = {
'type': 'file',
'name': disk_attrib.get('file'),
'dev': disk_target.get('dev'),
'bus': disk_target.get('bus'),
'rd_req': disk_stats.get('rd_req', 0),
'rd_bytes': disk_stats.get('rd_bytes', 0),
'wr_req': disk_stats.get('wr_req', 0),
'wr_bytes': disk_stats.get('wr_bytes', 0)
}
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))
except Exception:
domain_node_limit = None
try:
domain_node_selector = zkhandler.readdata(zk_conn, '/domains/{}/node_selector'.format(uuid))
except Exception:
domain_node_selector = None
try:
domain_node_autostart = zkhandler.readdata(zk_conn, '/domains/{}/node_autostart'.format(uuid))
except Exception:
domain_node_autostart = None
try:
domain_migration_method = zkhandler.readdata(zk_conn, '/domains/{}/migration_method'.format(uuid))
except Exception:
domain_migration_method = None
if not domain_node_limit:
domain_node_limit = None
else:
domain_node_limit = domain_node_limit.split(',')
if not domain_node_autostart:
domain_node_autostart = None
try:
domain_profile = zkhandler.readdata(zk_conn, '/domains/{}/profile'.format(uuid))
except Exception:
domain_profile = None
try:
domain_vnc = zkhandler.readdata(zk_conn, '/domains/{}/vnc'.format(uuid))
domain_vnc_listen, domain_vnc_port = domain_vnc.split(':')
except Exception:
domain_vnc_listen = 'None'
domain_vnc_port = 'None'
parsed_xml = getDomainXML(zk_conn, uuid)
try:
stats_data = loads(zkhandler.readdata(zk_conn, '/domains/{}/stats'.format(uuid)))
except Exception:
stats_data = {}
domain_uuid, domain_name, domain_description, domain_memory, domain_vcpu, domain_vcputopo = getDomainMainDetails(parsed_xml)
domain_networks = getDomainNetworks(parsed_xml, stats_data)
domain_type, domain_arch, domain_machine, domain_console, domain_emulator = getDomainExtraDetails(parsed_xml)
domain_features = getDomainCPUFeatures(parsed_xml)
domain_disks = getDomainDisks(parsed_xml, stats_data)
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': bool(strtobool(domain_node_autostart)),
'migration_method': domain_migration_method,
'description': domain_description,
'profile': domain_profile,
'memory': int(domain_memory),
'memory_stats': stats_data.get('mem_stats', {}),
'vcpu': int(domain_vcpu),
'vcpu_topology': domain_vcputopo,
'vcpu_stats': stats_data.get('cpu_stats', {}),
'networks': domain_networks,
'type': domain_type,
'arch': domain_arch,
'machine': domain_machine,
'console': domain_console,
'vnc': {
'listen': domain_vnc_listen,
'port': domain_vnc_port
},
'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, stats_data):
dnets = []
for device in parsed_xml.devices.getchildren():
if device.tag == 'interface':
try:
net_type = device.attrib.get('type')
except Exception:
net_type = None
try:
net_mac = device.mac.attrib.get('address')
except Exception:
net_mac = None
try:
net_bridge = device.source.attrib.get(net_type)
except Exception:
net_bridge = None
try:
net_model = device.model.attrib.get('type')
except Exception:
net_model = None
try:
net_stats_list = [x for x in stats_data.get('net_stats', []) if x.get('bridge') == net_bridge]
net_stats = net_stats_list[0]
except Exception:
net_stats = {}
net_rd_bytes = net_stats.get('rd_bytes', 0)
net_rd_packets = net_stats.get('rd_packets', 0)
net_rd_errors = net_stats.get('rd_errors', 0)
net_rd_drops = net_stats.get('rd_drops', 0)
net_wr_bytes = net_stats.get('wr_bytes', 0)
net_wr_packets = net_stats.get('wr_packets', 0)
net_wr_errors = net_stats.get('wr_errors', 0)
net_wr_drops = net_stats.get('wr_drops', 0)
net_obj = {
'type': net_type,
'vni': re_match(r'[vm]*br([0-9a-z]+)', net_bridge).group(1),
'mac': net_mac,
'source': net_bridge,
'model': net_model,
'rd_bytes': net_rd_bytes,
'rd_packets': net_rd_packets,
'rd_errors': net_rd_errors,
'rd_drops': net_rd_drops,
'wr_bytes': net_wr_bytes,
'wr_packets': net_wr_packets,
'wr_errors': net_wr_errors,
'wr_drops': net_wr_drops
}
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.get('type')
try:
controller_model = device.attrib.get('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 Exception:
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 Exception:
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 Exception:
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')
try:
current_node = zkhandler.readdata(zk_conn, '/domains/{}/node'.format(dom_uuid))
except kazoo.exceptions.NoNodeError:
current_node = None
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_provfree = 0
target_node = None
node_list = getNodes(zk_conn, node_limit, dom_uuid)
for node in node_list:
memprov = int(zkhandler.readdata(zk_conn, '/nodes/{}/memprov'.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
provfree = memtotal - memprov
if provfree > most_provfree:
most_provfree = provfree
target_node = node
return target_node
# via load average
def findTargetNodeLoad(zk_conn, node_limit, dom_uuid):
least_load = 9999.0
target_node = None
node_list = getNodes(zk_conn, node_limit, dom_uuid)
for node in node_list:
load = float(zkhandler.readdata(zk_conn, '/nodes/{}/cpuload'.format(node)))
if load < least_load:
least_load = load
target_node = 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.connect(node)
stdin, stdout, stderr = ssh_client.exec_command(command)
return stdout.read().decode('ascii').rstrip(), stderr.read().decode('ascii').rstrip()