python-compute/computelib/vm/installer.py
2023-09-23 21:24:56 +03:00

169 lines
5.6 KiB
Python

import textwrap
from dataclasses import dataclass
from enum import Enum
from lxml import etree
from lxml.builder import E
from ..utils import mac
from ..volume import DiskInfo, VolumeInfo
@dataclass
class VirtualMachineInfo:
name: str
title: str
memory: int
vcpus: int
machine: str
emulator: str
arch: str
cpu: str # CPU full XML description
mac: str
description: str = ''
boot_order: tuple = ('cdrom', 'hd')
def to_xml(self) -> str:
xml = E.domain(
E.name(self.name),
E.title(self.title),
E.description(self.description),
E.metadata(),
E.memory(str(self.memory), unit='MB'),
E.currentMemory(str(self.memory), unit='MB'),
E.vcpu(str(self.vcpus), placement='static'),
type='kvm')
os = E.os(E.type('hvm', machine=self.machine, arch=self.arch))
for dev in self.boot_order:
os.append(E.boot(dev=dev))
xml.append(os)
xml.append(E.features(E.acpi(), E.apic()))
xml.append(etree.fromstring(self.cpu))
xml.append(E.on_poweroff('destroy'))
xml.append(E.on_reboot('restart'))
xml.append(E.on_crash('restart'))
xml.append(E.pm(
E('suspend-to-mem', enabled='no'),
E('suspend-to-disk', enabled='no'))
)
devices = E.devices()
devices.append(E.emulator(self.emulator))
devices.append(E.interface(
E.source(network='default'),
E.mac(address=self.mac),
type='network'))
devices.append(E.graphics(type='vnc', port='-1', autoport='yes'))
devices.append(E.input(type='tablet', bus='usb'))
devices.append(E.channel(
E.source(mode='bind'),
E.target(type='virtio', name='org.qemu.guest_agent.0'),
E.address(type='virtio-serial', controller='0', bus='0', port='1'),
type='unix')
)
devices.append(E.console(
E.target(type='serial', port='0'),
type='pty')
)
devices.append(E.video(
E.model(type='vga', vram='16384', heads='1', primary='yes'))
)
xml.append(devices)
return etree.tostring(xml, encoding='unicode', pretty_print=True)
class CPUMode(Enum):
HOST_MODEL = 'host-model'
HOST_PASSTHROUGH = 'host-passthrough'
CUSTOM = 'custom'
MAXIMUM = 'maximum'
@classmethod
def default(cls):
return cls.HOST_PASSTHROUGH
@dataclass
class CPUTopology:
sockets: int
cores: int
threads: int
def validate(self, vcpus: int) -> None:
if self.sockets * self.cores * self.threads == vcpus:
return
raise ValueError("CPU topology must match the number of 'vcpus'")
class VirtualMachineInstaller:
def __init__(self, session: 'LibvirtSession'):
self.session = session
self.connection = session.connection # libvirt.virConnect object
self.domcaps = etree.fromstring(
self.connection.getDomainCapabilities())
self.arch = self.domcaps.xpath('/domainCapabilities/arch/text()')[0]
self.virttype = self.domcaps.xpath(
'/domainCapabilities/domain/text()')[0]
self.emulator = self.domcaps.xpath(
'/domainCapabilities/path/text()')[0]
self.machine = self.domcaps.xpath(
'/domainCapabilities/machine/text()')[0]
def install(self, data: 'VirtualMachineSchema'):
xml_cpu = self._choose_best_cpu(CPUMode.default())
xml_vm = VirtualMachineInfo(
name=data['name'],
title=data['title'],
vcpus=data['vcpus'],
memory=data['memory'],
machine=self.machine,
emulator=self.emulator,
arch=self.arch,
cpu=xml_cpu,
mac=mac.random_mac()
).to_xml()
self._define(xml_vm)
storage_pool = self.session.get_storage_pool('default')
etalon_vol = storage_pool.get_volume('bookworm.qcow2')
new_vol = VolumeInfo(
name=data['name'] +
'_disk_some_pattern.qcow2',
path=storage_pool.path +
'/' +
data['name'] +
'_disk_some_pattern.qcow2',
capacity=data['volume']['capacity'])
etalon_vol.clone(new_vol)
vm = self.session.get_machine(data['name'])
vm.attach_device(DiskInfo(path=new_vol.path, target='vda'))
vm.set_vcpus(data['vcpus'])
vm.set_memory(data['memory'])
vm.start()
vm.set_autostart(enabled=True)
def _choose_best_cpu(self, mode: CPUMode) -> str:
if mode == 'host-passthrough':
xml = '<cpu mode="host-passthrough" migratable="on"/>'
elif mode == 'maximum':
xml = '<cpu mode="maximum" migratable="on"/>'
elif mode in ['host-model', 'custom']:
cpus = self.domcaps.xpath(
f'/domainCapabilities/cpu/mode[@name="{mode}"]')[0]
cpus.tag = 'cpu'
for attr in cpus.attrib.keys():
del cpus.attrib[attr]
arch = etree.SubElement(cpus, 'arch')
arch.text = self.arch
xmlcpus = etree.tostring(
cpus, encoding='unicode', pretty_print=True)
xml = self.connection.baselineHypervisorCPU(
self.emulator, self.arch, self.machine, self.virttype, [xmlcpus])
else:
raise ValueError(
f'CPU mode must be in {[v.value for v in CPUMode]}, '
f"but passed '{mode}'")
return textwrap.indent(xml, ' ' * 2)
def _define(self, xml: str) -> None:
self.connection.defineXML(xml)