some updates

Makefile

@@ -1,4 +1,4 @@
-SRC = na/
+SRC = computelib/
 
 all: build
 

README.md

@@ -1,43 +1,28 @@
-# Compute Node Agent
+# Compute Node Agent library
 
-Агент для работы на ворк-нодах. В этом репозитории развивается базовая библиотека для взаимодействия с libvirt и выполнения основных операций.
+В этом репозитории развивается базовая библиотека для взаимодействия с libvirt и выполнения операций с виртуальными машинами. Фокус на QEMU/KVM.
 
-# Как это должно выглядеть
-
-`node-agent` должен стать обычным DEB-пакетом. Вместе с самим приложением пойдут вспомагательные утилиты:
-
-- `na-vmctl` virsh на минималках, который дёргает код из Node Agent. Выполняет базовые операции с VM, установку и миграцию и т.п. Реализована частично.
-- `na-vmexec`. Обёртка для вызова QEMU guest agent на машинах, больше нчего уметь не должна. Реализована целиком.
-- `na-volctl`. Предполагается здесь оставить всю работу с дисками. Не реализована.
-
-Этими утилитами нет цели заменять virsh, бцдет реализован только специфичный для Node Agent функционал.
-
-Зависимости (версии из APT репозитория Debian 12):
+# Зависимости (версии из APT репозитория Debian 12):
 
 - `python3-lxml` 4.9.2
 - `python3-docopt` 0.6.2
 - `python3-libvirt` 9.0.0
 
-`docopt` скорее всего будет выброшен в будущем, так как интерфейс CLI сильно усложнится.
-
 Минимальная поддерживаемая версия Python — `3.11`, потому, что можем.
 
+# Утилиты
+
+- `na-vmctl` virsh на минималках. Выполняет базовые операции с VM, установку и миграцию и т.п.
+- `na-vmexec`. Обёртка для вызова QEMU guest agent на машинах, больше нчего уметь не должна.
+- `na-volctl`. Предполагается здесь оставить всю работу с дисками. Не реализована.
+
 # API
 
 Кодовая база растёт, необходимо автоматически генерировать документацию, в README её больше не будет.
 
 В структуре проекта сейчас бардак, многое будет переосмыслено и переделано позже. Основная цель на текущем этапе — получить минимально работающий код, с помощью которого возможно выполнить установку виртуальной машины и как-то управлять ею.
 
-Базовые сущности:
-
-- `LivbirtSession` - обёртка над объектом `libvirt.virConnect`.
-- `VirtualMachine` - класс для работы с доменами, через него выполняется большинство действий.
-- `VirtualMachineInstaller` - класс для установки ВМ, выполняет кучу проверок, генерирует XML конфиг и т.п. [В ПРОЦЕССЕ]
-- `StoragePool` - обёртка над `libvirt.virStoragePool`.
-- `Volume` - класс для управления дисками.
-- `VolumeInfo` - датакласс хранящий информацию о диске, с помощью метода `to_xml()` получаем XML описание.
-- `GuestAgent` - понятно что это.
-- `ConfigLoader` - загрузчик TOML-конфига.
+Есть набор классов, предоставляющих собой интерфейсы для взаимодействия с виртуальными машинами, стораджами, дисками и т.п. Датаклассы описывают сущности и имеют метод `to_xml()` для получения XML конфига для `libvirt`. Смысл датакласса в том, чтобы иметь один объект, содержащий в себе нормальные легкочитаемые аттрибуты и XML описание сущности одновременно.
 
 # TODO
 
@@ -49,12 +34,20 @@
     - [x] Работа со StoragePool
     - [x] Создание блочных устройств
     - [x] Подключение/отключение устройств
-    - [ ] Метод install()
+    - [x] Метод install()
+    - [ ] Выбор между SeaBIOS/UEFI
+    - [ ] Выбор модели процессора
 - [ ] Установка ВМ (нормальный вариант)
-- [x] Управление дисками (всратый вариант)
+- [x] Управление дисками
+    - [x] Локальные qcow2
+    - [ ] ZVOL
+    - [ ] Сетевые диски
+    - [ ] Живой ресайз файловой системы (?)
 - [x] Удаление ВМ
 - [x] Изменение CPU
+    - [ ] Полноценный hotplug
 - [x] Изменение RAM
+    - [ ] Полноценный hotplug
 - [ ] Миграция ВМ между нодами
 - [x] Работа с qemu-ga
 - [x] Управление питанием
@@ -68,15 +61,15 @@
 
 # Заметки
 
-## Что там с LXC?
+### Что там с LXC?
 
 Можно добавить поддержку LXC, но только после реализации основного функционала для QEMU/KVM.
 
-## Будущее этой библиотеки
+### Будущее этой библиотеки
 
-Нужно ей придумать название.
+Нужно задействовать билиотеку [libosinfo](https://libosinfo.org/) для получения информации об операционных системах. См. [How to populate Libosinfo DataBase](https://wiki.libvirt.org/HowToPopulateLibosinfoDB.html).
 
-## Failover
+### Failover
 
 В перспективе для ВМ с сетевыми дисками возможно организовать Failover решение — ВМ будет автоматически запускаться на другой ноде из пула при отключении оригинальной ноды. Технически это можно реализовать как создание ВМ с аналогичными характеристиками на другой ноде с подключением к тому же самому сетевому диску. Сразу нужно отметить, что для реализации:
 

computelib/__init__.py

@@ -1,5 +1,5 @@
 from .config import ConfigLoader
-from .session import LibvirtSession
 from .exceptions import *
-from .volume import *
+from .session import LibvirtSession
 from .vm import *
+from .volume import *

computelib/cli/vmctl.py

@@ -22,9 +22,9 @@ import sys
 import libvirt
 from docopt import docopt
 
+from ..exceptions import VMError, VMNotFound
 from ..session import LibvirtSession
 from ..vm import VirtualMachine
-from ..exceptions import VMError, VMNotFound
 
 
 logger = logging.getLogger(__name__)

computelib/cli/vmexec.py

@@ -18,9 +18,9 @@ import sys
 import libvirt
 from docopt import docopt
 
+from ..exceptions import GuestAgentError, VMNotFound
 from ..session import LibvirtSession
 from ..vm import GuestAgent
-from ..exceptions import GuestAgentError, VMNotFound
 
 
 logger = logging.getLogger(__name__)

computelib/exceptions.py

@@ -1,6 +1,7 @@
 class ConfigLoaderError(Exception):
     """Bad config file syntax, unreachable file or bad config schema."""
 
+
 class LibvirtSessionError(Exception):
     """Something went wrong while connecting to libvirtd."""
 

computelib/session.py

@@ -2,15 +2,18 @@ from contextlib import AbstractContextManager
 
 import libvirt
 
+from .exceptions import LibvirtSessionError, VMNotFound
 from .vm import GuestAgent, VirtualMachine
 from .volume import StoragePool
-from .exceptions import LibvirtSessionError, VMNotFound
 
 
 class LibvirtSession(AbstractContextManager):
 
     def __init__(self, uri: str = 'qemu:///system'):
-        self.connection = self._connect(uri)
+        try:
+            self.connection = libvirt.open(uri)
+        except libvirt.libvirtError as err:
+            raise LibvirtSessionError(err) from err
 
     def __enter__(self):
         return self
@@ -18,47 +21,31 @@ class LibvirtSession(AbstractContextManager):
     def __exit__(self, exception_type, exception_value, exception_traceback):
         self.close()
 
-    def _connect(self, connection_uri: str) -> libvirt.virConnect:
+    def get_machine(self, name: str) -> VirtualMachine:
         try:
-            return libvirt.open(connection_uri)
-        except libvirt.libvirtError as err:
-            raise LibvirtSessionError(
-                f'Failed to open connection to the hypervisor: {err}') from err
-
-    def _get_domain(self, name: str) -> libvirt.virDomain:
-        try:
-            return self.connection.lookupByName(name)
+            return VirtualMachine(self.connection.lookupByName(name))
         except libvirt.libvirtError as err:
             if err.get_error_code() == libvirt.VIR_ERR_NO_DOMAIN:
                 raise VMNotFound(name) from err
             raise LibvirtSessionError(err) from err
 
-    def _list_all_domains(self) -> list[libvirt.virDomain]:
-        try:
-            return self.connection.listAllDomains()
-        except libvirt.libvirtError as err:
-            raise LibvirtSessionError(err) from err
-
-    def _get_storage_pool(self, name: str) -> libvirt.virStoragePool:
-        try:
-            return self.connection.storagePoolLookupByName(name)
-        except libvirt.libvirtError as err:
-            raise LibvirtSessionError(err) from err
-
-    def get_machine(self, name: str) -> VirtualMachine:
-        return VirtualMachine(self._get_domain(name))
-
     def list_machines(self) -> list[VirtualMachine]:
-        return [VirtualMachine(dom) for dom in self._list_all_domains()]
+        return [VirtualMachine(dom) for dom in
+                self.connection.listAllDomains()]
 
-    def get_guest_agent(self, name: str, timeout: int | None = None,
-                        flags: int | None = None) -> GuestAgent:
-        return GuestAgent(self._get_domain(name), timeout, flags)
+    def get_guest_agent(self, name: str,
+                        timeout: int | None = None) -> GuestAgent:
+        try:
+            return GuestAgent(self.connection.lookupByName(name), timeout)
+        except libvirt.libvirtError as err:
+            if err.get_error_code() == libvirt.VIR_ERR_NO_DOMAIN:
+                raise VMNotFound(name) from err
+            raise LibvirtSessionError(err) from err
 
     def get_storage_pool(self, name: str) -> StoragePool:
-        return StoragePool(self._get_storage_pool(name))
+        return StoragePool(self.connection.storagePoolLookupByName(name))
 
-    def list_storage_pools(self):
+    def list_storage_pools(self) -> list[StoragePool]:
         return [StoragePool(p) for p in self.connection.listStoragePools()]
 
     def close(self) -> None:

computelib/utils/xml.py

@@ -0,0 +1,73 @@
+from lxml.etree import Element, QName, SubElement
+
+
+class Constructor:
+    """
+    The XML constructor. This class builds XML configs for libvirt.
+    """
+
+    def construct_xml(self,
+                      tag: dict,
+                      namespace: str | None = None,
+                      nsprefix: str | None = None,
+                      root: Element = None) -> Element:
+        """
+        Shortly this recursive function transforms dictonary to XML.
+        Return etree.Element built from dict with following structure::
+
+            {
+                'name': 'device',  # tag name
+                'text': '',  # optional key
+                'values': {  # optional key, must be a dict of key-value pairs
+                    'type': 'disk'
+                },
+                children: []  # optional key, must be a list of dicts
+            }
+
+        Child elements must have the same structure. Infinite `children` nesting
+        is allowed.
+        """
+        use_ns = False
+        if isinstance(namespace, str) and isinstance(nsprefix, str):
+            use_ns = True
+        # Create element
+        if root is None:
+            if use_ns:
+                element = Element(QName(namespace, tag['name']),
+                                  nsmap={nsprefix: namespace})
+            else:
+                element = Element(tag['name'])
+        else:
+            if use_ns:
+                element = SubElement(root, QName(namespace, tag['name']))
+            else:
+                element = SubElement(root, tag['name'])
+        # Fill up element with content
+        if 'text' in tag.keys():
+            element.text = tag['text']
+        if 'values' in tag.keys():
+            for key in tag['values'].keys():
+                element.set(str(key), str(tag['values'][key]))
+        if 'children' in tag.keys():
+            for child in tag['children']:
+                element.append(
+                    self.construct_xml(child,
+                                       namespace=namespace,
+                                       nsprefix=nsprefix,
+                                       root=element))
+        return element
+
+    def add_meta(self, xml: Element, data: dict,
+                 namespace: str, nsprefix: str) -> None:
+        """
+        Add metadata to domain. See:
+        https://libvirt.org/formatdomain.html#general-metadata
+        """
+        metadata = metadata_old = xml.xpath('/domain/metadata')[0]
+        metadata.append(
+            self.construct_xml(
+                data,
+                namespace=namespace,
+                nsprefix=nsprefix,
+            ))
+        xml.replace(metadata_old, metadata)

computelib/vm/__init__.py

@@ -1,3 +1,3 @@
 from .guest_agent import GuestAgent
-from .installer import CPUMode, CPUTopology, VirtualMachineInstaller
+from .installer import VirtualMachineInstaller
 from .virtual_machine import VirtualMachine

computelib/vm/guest_agent.py

@@ -26,6 +26,9 @@ class GuestAgent(VirtualMachineBase):
     shellexec()
         High-level method for executing shell commands on guest. Command
         must be passed as string. Wraps execute() method.
+
+    TODO:
+        check() method. Ping guest agent and check supported commands.
     """
 
     def __init__(self, domain: libvirt.virDomain, timeout: int | None = None,

computelib/vm/installer.py

@@ -0,0 +1,168 @@
+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)

computelib/vm/virtual_machine.py

@@ -156,7 +156,7 @@ class VirtualMachine(VirtualMachineBase):
         if nvcpus == 0:
             raise VMError(f'Cannot set zero vCPUs vm={self.domain_name}')
         if hotplug and self.domain_info['state'] == libvirt.VIR_DOMAIN_RUNNING:
-            flags = (libvirt.VIR_DOMAIN_AFFECT_LIVE +
+            flags = (libvirt.VIR_DOMAIN_AFFECT_LIVE |
                      libvirt.VIR_DOMAIN_AFFECT_CONFIG)
         else:
             flags = libvirt.VIR_DOMAIN_AFFECT_CONFIG
@@ -177,31 +177,33 @@ class VirtualMachine(VirtualMachineBase):
         if memory == 0:
             raise VMError(f'Cannot set zero memory vm={self.domain_name}')
         if hotplug and self.domain_info['state'] == libvirt.VIR_DOMAIN_RUNNING:
-            flags = (libvirt.VIR_DOMAIN_AFFECT_LIVE +
+            flags = (libvirt.VIR_DOMAIN_AFFECT_LIVE |
                      libvirt.VIR_DOMAIN_AFFECT_CONFIG)
         else:
             flags = libvirt.VIR_DOMAIN_AFFECT_CONFIG
         try:
-            self.domain.setVcpusFlags(memory * 1024, flags=flags)
+            self.domain.setMemoryFlags(memory * 1024,
+                                       libvirt.VIR_DOMAIN_MEM_MAXIMUM)
+            self.domain.setMemoryFlags(memory * 1024, flags=flags)
         except libvirt.libvirtError as err:
             raise VMError(
-                f'Cannot set memory for vm={self.domain_name}: {err}') from err
+                f'Cannot set memory for vm={self.domain_name} {memory=}: {err}') from err
 
-    def attach_device(self, dev_xml: str, hotplug: bool = False):
+    def attach_device(self, device_info: 'DeviceInfo', hotplug: bool = False):
         if hotplug and self.domain_info['state'] == libvirt.VIR_DOMAIN_RUNNING:
-            flags = (libvirt.VIR_DOMAIN_AFFECT_LIVE +
+            flags = (libvirt.VIR_DOMAIN_AFFECT_LIVE |
                      libvirt.VIR_DOMAIN_AFFECT_CONFIG)
         else:
             flags = libvirt.VIR_DOMAIN_AFFECT_CONFIG
-        self.domain.attachDeviceFlags(dev_xml, flags=flags)
+        self.domain.attachDeviceFlags(device_info.to_xml(), flags=flags)
 
-    def detach_device(self, dev_xml: str, hotplug: bool = False):
+    def detach_device(self, device_info: 'DeviceInfo', hotplug: bool = False):
         if hotplug and self.domain_info['state'] == libvirt.VIR_DOMAIN_RUNNING:
-            flags = (libvirt.VIR_DOMAIN_AFFECT_LIVE +
+            flags = (libvirt.VIR_DOMAIN_AFFECT_LIVE |
                      libvirt.VIR_DOMAIN_AFFECT_CONFIG)
         else:
             flags = libvirt.VIR_DOMAIN_AFFECT_CONFIG
-        self.domain.detachDeviceFlags(dev_xml, flags=flags)
+        self.domain.detachDeviceFlags(device_info.to_xml(), flags=flags)
 
     def resize_volume(self, vol_info: VolumeInfo, online: bool = False):
         # Этот метод должен принимать описание волюма и в зависимости от
@@ -218,13 +220,14 @@ class VirtualMachine(VirtualMachineBase):
     def remove_ssh_keys(self, user: str):
         pass
 
-    def set_user_password(self, user: str, password: str):
+    def set_user_password(self, user: str, password: str) -> None:
         self.domain.setUserPassword(user, password)
 
     def dump_xml(self) -> str:
         return self.domain.XMLDesc()
 
-    def delete(self, delete_volumes: bool = False):
+    def delete(self, delete_volumes: bool = False) -> None:
         """Undefine VM."""
         self.shutdown(method='SIGTERM')
         self.domain.undefine()
+        # todo: delete local volumes

computelib/volume/__init__.py

@@ -0,0 +1,2 @@
+from .storage_pool import StoragePool
+from .volume import DiskInfo, Volume, VolumeInfo

computelib/volume/storage_pool.py

@@ -1,6 +1,8 @@
 import logging
+from collections import namedtuple
 
 import libvirt
+from lxml import etree
 
 from ..exceptions import StoragePoolError
 from .volume import Volume, VolumeInfo
@@ -17,15 +19,24 @@ class StoragePool:
     def name(self) -> str:
         return self.pool.name()
 
+    @property
+    def path(self) -> str:
+        xml = etree.fromstring(self.pool.XMLDesc())
+        return xml.xpath('/pool/target/path/text()')[0]
+
+    @property
+    def usage(self) -> 'StoragePoolUsage':
+        xml = etree.fromstring(self.pool.XMLDesc())
+        StoragePoolUsage = namedtuple('StoagePoolUsage',
+                                      ['capacity', 'allocation', 'available'])
+        return StoragePoolUsage(
+            capacity=int(xml.xpath('/pool/capacity/text()')[0])
+            allocation=int(xml.xpath('/pool/allocation/text()')[0])
+            available=int(xml.xpath('/pool/available/text()')[0]))
+
     def dump_xml(self) -> str:
         return self.pool.XMLDesc()
 
-    def create(self):
-        pass
-
-    def delete(self):
-        pass
-
     def refresh(self) -> None:
         self.pool.refresh()
 
@@ -33,30 +44,27 @@ class StoragePool:
         """
         Create storage volume and return Volume instance.
         """
-        logger.info(f'Create storage volume vol={vol_info.name} '
-                    f'in pool={self.pool}')
+        logger.info('Create storage volume vol=%s in pool=%s',
+                    vol_info.name, self.pool)
         vol = self.pool.createXML(
             vol_info.to_xml(),
             flags=libvirt.VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA)
         return Volume(self.pool, vol)
 
     def get_volume(self, name: str) -> Volume | None:
-        """
-        Lookup and return Volume instance or None.
-        """
-        logger.info(f'Lookup for storage volume vol={name} '
-                    f'in pool={self.pool.name}')
+        """Lookup and return Volume instance or None."""
+        logger.info('Lookup for storage volume vol=%s in pool=%s',
+                    name, self.pool.name)
         try:
             vol = self.pool.storageVolLookupByName(name)
             return Volume(self.pool, vol)
         except libvirt.libvirtError as err:
-            if (err.get_error_domain() == libvirt.VIR_FROM_STORAGE
-                err.get_error_code() == libvirt.VIR_ERR_NO_STORAGE_VOL):
+            if (err.get_error_domain() == libvirt.VIR_FROM_STORAGE or
+                    err.get_error_code() == libvirt.VIR_ERR_NO_STORAGE_VOL):
                 logger.error(err.get_error_message())
                 return None
-            else:
-                logger.error(f'libvirt error: {err}')
-                raise StoragePoolError(f'libvirt error: {err}') from err
+            logger.error('libvirt error: %s' err)
+            raise StoragePoolError(f'libvirt error: {err}') from err
 
     def list_volumes(self) -> list[Volume]:
         return [Volume(self.pool, vol) for vol in self.pool.listAllVolumes()]

computelib/volume/volume.py

@@ -2,8 +2,8 @@ from dataclasses import dataclass
 from time import time
 
 import libvirt
+from lxml import etree
 from lxml.builder import E
-from lxml.etree import tostring
 
 
 @dataclass
@@ -30,7 +30,23 @@ class VolumeInfo:
             E.compat('1.1'),
             E.features(E.lazy_refcounts())
         ))
-        return tostring(xml, encoding='unicode', pretty_print=True)
+        return etree.tostring(xml, encoding='unicode', pretty_print=True)
+
+
+@dataclass
+class DiskInfo:
+    target: str
+    path: str
+    readonly: bool = False
+
+    def to_xml(self) -> str:
+        xml = E.disk(type='file', device='disk')
+        xml.append(E.driver(name='qemu', type='qcow2', cache='writethrough'))
+        xml.append(E.source(file=self.path))
+        xml.append(E.target(dev=self.target, bus='virtio'))
+        if self.readonly:
+            xml.append(E.readonly())
+        return etree.tostring(xml, encoding='unicode', pretty_print=True)
 
 
 class Volume:

config.toml

@@ -1,26 +1,26 @@
 [libvirt]
-uri = 'qemu:///session'
+uri = 'qemu:///system'
 
 [logging]
 level = 'INFO'
 driver = 'file'
-file = '/var/log/node-agent.log'
+file = '/var/log/compute/compute.log'
 
 [[storages.pools]]
 name = 'ssd-nvme'
 enabled = true
 default = true
-path = '/srv/vm-volumes/ssd-nvme'
+path = '/vm-volumes/ssd-nvme'
 
 [[storages.pools]]
 name = 'hdd'
 enabled = true
-path = '/srv/vm-volumes/hdd'
+path = '/vm-volumes/hdd'
 
 [[storages.pools]]
 name = 'images'
 enabled = true
-path = '/srv/vm-images/vendor'
+path = '/vm-images/vendor'
 
 [virtual_machine.defaults]
 autostart = true

node_agent/utils/xml.py

@@ -1,145 +0,0 @@
-from lxml.builder import E
-from lxml.etree import Element, QName, SubElement, fromstring, tostring
-
-
-class Constructor:
-    """
-    The XML constructor. This class builds XML configs for libvirt.
-    """
-
-    def gen_domain_xml(self, name: str, title: str, desc: str, memory: int,
-                       vcpus: int, domain_type: str, machine: str, arch: str,
-                       boot_order: tuple, cpu: str, mac: str) -> str:
-        """
-        Return basic libvirt domain configuration.
-        """
-        domain = E.domain(
-            E.name(name),
-            E.title(title),
-            E.description(desc),
-            E.metadata(),
-            E.memory(str(memory), unit='MB'),
-            E.currentMemory(str(memory), unit='MB'),
-            E.vcpu(str(vcpus), placement='static'),
-            type='kvm'
-        )
-        os = E.os(E.type(domain_type, machine=machine, arch=arch))
-        for dev in boot_order:
-            os.append(E.boot(dev=dev))
-        domain.append(os)
-        domain.append(E.features(E.acpi(), E.apic()))
-        domain.append(fromstring(cpu))
-        domain.append(E.on_poweroff('destroy'))
-        domain.append(E.on_reboot('restart'))
-        domain.append(E.on_crash('restart'))
-        domain.append(E.pm(
-            E('suspend-to-mem', enabled='no'),
-            E('suspend-to-disk', enabled='no'))
-        )
-        devices = E.devices()
-        devices.append(E.emulator('/usr/bin/qemu-system-x86_64'))
-        devices.append(E.interface(
-            E.source(network='default'),
-            E.mac(address=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'))
-        )
-        domain.append(devices)
-        return tostring(domain, encoding='unicode', pretty_print=True).strip()
-
-    def gen_volume_xml(self, dev: str, mode: str, path: str) -> str:
-        """
-        Todo: No hardcode
-        https://libvirt.org/formatdomain.html#hard-drives-floppy-disks-cdroms
-        """
-        volume = E.disk(type='file', device='disk')
-        volume.append(
-            E.driver(
-                name='qemu',
-                type='qcow2',
-                cache='writethrough'))
-        volume.append(E.source(file=path))
-        volume.append(E.target(dev=dev, bus='virtio'))
-        if mode.lower() == 'ro':
-            volume.append(E.readonly())
-        return tostring(volume, encoding='unicode', pretty_print=True).strip()
-
-    def construct_xml(self,
-                      tag: dict,
-                      namespace: str | None = None,
-                      nsprefix: str | None = None,
-                      root: Element = None) -> Element:
-        """
-        Shortly this recursive function transforms dictonary to XML.
-        Return etree.Element built from dict with following structure::
-
-            {
-                'name': 'device',  # tag name
-                'text': '',  # optional key
-                'values': {  # optional key, must be a dict of key-value pairs
-                    'type': 'disk'
-                },
-                children: []  # optional key, must be a list of dicts
-            }
-
-        Child elements must have the same structure. Infinite `children` nesting
-        is allowed.
-        """
-        use_ns = False
-        if isinstance(namespace, str) and isinstance(nsprefix, str):
-            use_ns = True
-        # Create element
-        if root is None:
-            if use_ns:
-                element = Element(QName(namespace, tag['name']),
-                                  nsmap={nsprefix: namespace})
-            else:
-                element = Element(tag['name'])
-        else:
-            if use_ns:
-                element = SubElement(root, QName(namespace, tag['name']))
-            else:
-                element = SubElement(root, tag['name'])
-        # Fill up element with content
-        if 'text' in tag.keys():
-            element.text = tag['text']
-        if 'values' in tag.keys():
-            for key in tag['values'].keys():
-                element.set(str(key), str(tag['values'][key]))
-        if 'children' in tag.keys():
-            for child in tag['children']:
-                element.append(
-                    self.construct_xml(child,
-                                       namespace=namespace,
-                                       nsprefix=nsprefix,
-                                       root=element))
-        return element
-
-    def add_meta(self, xml: Element, data: dict,
-                 namespace: str, nsprefix: str) -> None:
-        """
-        Add metadata to domain. See:
-        https://libvirt.org/formatdomain.html#general-metadata
-        """
-        metadata = metadata_old = xml.xpath('/domain/metadata')[0]
-        metadata.append(
-            self.construct_xml(
-                data,
-                namespace=namespace,
-                nsprefix=nsprefix,
-            ))
-        xml.replace(metadata_old, metadata)

node_agent/vm/installer.py

@@ -1,190 +0,0 @@
-import re
-import textwrap
-from dataclasses import dataclass
-from enum import Enum
-from pathlib import Path
-from uuid import UUID
-
-from lxml.etree import SubElement, fromstring, tostring
-
-from ..utils import mac, xml
-
-
-class CPUMode(Enum):
-    HOST_MODEL = 'host-model'
-    HOST_PASSTHROUGH = 'host-passthrough'
-    CUSTOM = 'custom'
-    MAXIMUM = 'maximum'
-
-    @classmethod
-    def default(cls):
-        return cls.HOST_MODEL
-
-
-@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'")
-
-
-@dataclass
-class CPUInfo:
-    vendor: str
-    model: str
-    required_features: list[str]
-    disabled_features: list[str]
-
-
-@dataclass
-class VolumeInfo:
-    name: str
-    path: Path
-    capacity: int
-
-
-@dataclass
-class CloudInitConfig:
-    user_data: str = ''
-    meta_data: str = ''
-
-
-class Boot(Enum):
-    BIOS = 'bios'
-    UEFI = 'uefi'
-
-    @classmethod
-    def default(cls):
-        return cls.BIOS
-
-
-@dataclass
-class BootMenu:
-    enabled: bool = False
-    timeout: int = 3000
-
-
-class VirtualMachineInstaller:
-
-    def __init__(self, session: 'LibvirtSession'):
-        self.connection = session.connection  # libvirt.virConnect object
-        self.domcaps = 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,
-            name: str | None = None,
-            title: str | None = None,
-            description: str = '',
-            os: str | None = None,
-            image: UUID | None = None,
-            volumes: list['VolumeInfo'] | None = None,
-            vcpus: int = 0,
-            vcpu_info: CPUInfo | None = None,
-            vcpu_mode: CPUMode = CPUMode.default(),
-            vcpu_topology: CPUTopology | None = None,
-            memory: int = 0,
-            boot: Boot = Boot.default(),
-            boot_menu: BootMenu = BootMenu(),
-            boot_order: tuple[str] = ('cdrom', 'hd'),
-            cloud_init: CloudInitConfig | None = None):
-        """
-        Install virtual machine with passed parameters.
-
-        If no `vcpu_info` is None select best CPU wich can be provided by
-        hypervisor. Choosen CPU depends on `vcpu_mode`, default is 'custom'.
-        See CPUMode for more info. Default `vcpu_topology` is: 1 socket,
-        `vcpus` cores, 1 threads.
-
-        `memory` must be integer value in mebibytes e.g. 4094 MiB = 4 GiB.
-
-        Volumes must be passed as list of VolumeInfo objects. Minimum one
-        volume is required.
-        """
-        name = self._validate_name(name)
-
-        if vcpu_topology is None:
-            vcpu_topology = CPUTopology(sockets=1, cores=vcpus, threads=1)
-        vcpu_topology.validate(vcpus)
-
-        if vcpu_info is None:
-            if not vcpu_mode:
-                vcpu_mode = CPUMode.CUSTOM.value
-            xml_cpu = self._choose_best_cpu(vcpu_mode)
-        else:
-            raise NotImplementedError('Custom CPU not implemented')
-
-        xml_domain = xml.Constructor().gen_domain_xml(
-            name=name,
-            title=title if title else name,
-            desc=description if description else '',
-            vcpus=vcpus,
-            # vcpu_topology=vcpu_topology,
-            # vcpu_info=vcpu_info,
-            memory=memory,
-            domain_type='hvm',
-            machine=self.machine,
-            arch=self.arch,
-            # boot_menu=boot_menu,
-            boot_order=boot_order,
-            cpu=xml_cpu,
-            mac=mac.random_mac()
-        )
-        xml_volume = xml.Constructor().gen_volume_xml(
-            dev='vda', mode='rw', path='')
-
-        virconn = self.connection
-
-        virstor = virconn.storagePoolLookupByName('default')
-        # Мб использовать storageVolLookupByPath вместо поиска по имени
-        etalon_volume = virstor.storageVolLookupByName('debian_bookworm.qcow2')
-
-        return xml_domain
-
-    def _validate_name(self, name) -> str:
-        if name is None:
-            raise ValueError("'name' cannot be empty")
-        if isinstance(name, str):
-            if not re.match(r"^[a-z0-9_]+$", name, re.I):
-                raise ValueError(
-                    "'name' can contain only letters, numbers "
-                    "and underscore.")
-            return name.lower()
-        raise TypeError(f"'name' must be 'str', not {type(name)}")
-
-    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 = SubElement(cpus, 'arch')
-            arch.text = self.arch
-            xmlcpus = 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)

node_agent/volume/__init__.py

@@ -1,2 +0,0 @@
-from .storage_pool import StoragePool
-from .volume import Volume, VolumeInfo

pyproject.toml

@@ -1,26 +1,24 @@
 [tool.poetry]
-name = "node-agent"
+name = "computelib"
 version = "0.1.0"
-description = "Node Agent"
+description = "Compute Node Agent library"
 authors = ["ge <ge@nixhacks.net>"]
 readme = "README.md"
 
 [tool.poetry.dependencies]
 python = "^3.11"
-libvirt-python = "9.0.0"  # 9.0.0 on Debian 12
-lxml = "^4.9.2"  # 4.9.2 on Debian 12
-docopt = "^0.6.2"  # 0.6.2 on Debian 12
+libvirt-python = "9.0.0"
+lxml = "^4.9.2"
+docopt = "^0.6.2"
 
 [tool.poetry.scripts]
-na-vmctl = "node_agent.cli.vmctl:cli"
-na-vmexec = "node_agent.cli.vmexec:cli"
+na-vmctl = "computelib.cli.vmctl:cli"
+na-vmexec = "computelib.cli.vmexec:cli"
 
 [build-system]
 requires = ["poetry-core"]
 build-backend = "poetry.core.masonry.api"
 
-[tool.yapf]
-
 [tool.pylint."MESSAGES CONTROL"]
 disable = [
     "invalid-name",
@@ -30,4 +28,3 @@ disable = [
     "import-error",
     "too-many-arguments",
 ]
-