upd

node_agent/vm/__init__.py

@@ -1,3 +1,5 @@
 from .exceptions import *
-from .ga import QemuAgent
-from .main import VirtualMachine
+from .guest_agent import QemuAgent
+from .virtual_machine import VirtualMachine
+from .installer import VirtualMachineInstaller
+from .hardware import vCPUMode, vCPUTopology

node_agent/vm/base.py

@@ -1,22 +1,31 @@
 import libvirt
 
-from .exceptions import VMError, VMNotFound
+from .exceptions import VMError
 
 
 class VirtualMachineBase:
 
-    def __init__(self, session: 'LibvirtSession', name: str):
-        self.domname = name
-        self.session = session.session  # virConnect object
-        self.config = session.config  # ConfigLoader object
-        self.domain = self._get_domain(name)
+    def __init__(self, domain: libvirt.virDomain):
+        self.domain = domain
+        self.domain_name = self._get_domain_name()
+        self.domain_info = self._get_domain_info()
 
-    def _get_domain(self, name: str) -> libvirt.virDomain:
-        """Get virDomain object by name to manipulate with domain."""
+    def _get_domain_name(self):
         try:
-            domain = self.session.lookupByName(name)
-            if domain is not None:
-                return domain
-            raise VMNotFound(name)
+            return self.domain.name()
         except libvirt.libvirtError as err:
-            raise VMError(err) from err
+            raise VMError(f'Cannot get domain name: {err}') from err
+
+    def _get_domain_info(self):
+        # https://libvirt.org/html/libvirt-libvirt-domain.html#virDomainInfo
+        try:
+            info = self.domain.info()
+            return {
+                'state': info[0],
+                'max_memory': info[1],
+                'memory': info[2],
+                'nproc': info[3],
+                'cputime': info[4]
+            }
+        except libvirt.libvirtError as err:
+            raise VMError(f'Cannot get domain info: {err}') from err

node_agent/vm/exceptions.py

@@ -8,7 +8,7 @@ class VMError(Exception):
 
 class VMNotFound(Exception):
 
-    def __init__(self, domain, message='VM not found: {domain}'):
+    def __init__(self, domain, message='VM not found vm={domain}'):
         self.domain = domain
         self.message = message.format(domain=domain)
         super().__init__(self.message)

node_agent/vm/guest_agent.py

@@ -12,8 +12,9 @@ from .exceptions import QemuAgentError
 
 logger = logging.getLogger(__name__)
 
-QEMU_TIMEOUT = 60  # seconds
-POLL_INTERVAL = 0.3  # also seconds
+# Note that if no QEMU_TIMEOUT libvirt cannot connect to agent
+QEMU_TIMEOUT = 60  # in seconds
+POLL_INTERVAL = 0.3  # also in seconds
 
 
 class QemuAgent(VirtualMachineBase):
@@ -28,12 +29,9 @@ class QemuAgent(VirtualMachineBase):
         must be passed as string. Wraps execute() method.
     """
 
-    def __init__(self,
-                 session: 'LibvirtSession',
-                 name: str,
-                 timeout: int | None = None,
+    def __init__(self, domain: libvirt.virDomain, timeout: int | None = None,
                  flags: int | None = None):
-        super().__init__(session, name)
+        super().__init__(domain)
         self.timeout = timeout or QEMU_TIMEOUT  # timeout for guest agent
         self.flags = flags or libvirt_qemu.VIR_DOMAIN_QEMU_MONITOR_COMMAND_DEFAULT
 
@@ -110,7 +108,11 @@ class QemuAgent(VirtualMachineBase):
         )
 
     def _execute(self, command: dict):
-        logging.debug('Execute command: vm=%s cmd=%s', self.domname, command)
+        logging.debug('Execute command: vm=%s cmd=%s', self.domain_name,
+                      command)
+        if self.domain_info['state'] != libvirt.VIR_DOMAIN_RUNNING:
+            raise GuestAgentError(
+                f'Cannot execute command: vm={self.domain_name} is not running')
         try:
             return libvirt_qemu.qemuAgentCommand(
                 self.domain,  # virDomain object
@@ -119,7 +121,9 @@ class QemuAgent(VirtualMachineBase):
                 self.flags,
             )
         except libvirt.libvirtError as err:
-            raise QemuAgentError(err) from err
+            raise QemuAgentError(
+                    f'Cannot execute command on vm={self.domain_name}: {err}'
+                ) from err
 
     def _get_cmd_result(
             self, pid: int, decode_output: bool = False, wait: bool = True,
@@ -131,7 +135,8 @@ class QemuAgent(VirtualMachineBase):
             output = json.loads(self._execute(cmd))
             return self._return_tuple(output, decode=decode_output)
 
-        logger.debug('Start polling command pid=%s', pid)
+        logger.debug('Start polling command pid=%s on vm=%s', pid,
+                     self.domain_name)
         start_time = time()
         while True:
             output = json.loads(self._execute(cmd))
@@ -141,10 +146,12 @@ class QemuAgent(VirtualMachineBase):
             now = time()
             if now - start_time > timeout:
                 raise QemuAgentError(
-                    f'Polling command pid={pid} took longer than {timeout} seconds.'
+                    f'Polling command pid={pid} on vm={self.domain_name} '
+                    f'took longer than {timeout} seconds.'
                 )
-        logger.debug('Polling command pid=%s finished, time taken: %s seconds',
-                     pid, int(time() - start_time))
+        logger.debug('Polling command pid=%s on vm=%s finished, '
+                     'time taken: %s seconds',
+                     pid, self.domain_name, int(time() - start_time))
         return self._return_tuple(output, decode=decode_output)
 
     def _return_tuple(self, output: dict, decode: bool = False):

node_agent/vm/hardware.py

@@ -0,0 +1,81 @@
+import textwrap
+from enum import Enum
+from collections import UserDict
+
+import libvirt
+from lxml.etree import SubElement, fromstring, tostring
+
+
+class Boot(Enum):
+    BIOS = 'bios'
+    UEFI = 'uefi'
+
+
+class vCPUMode(Enum):
+    HOST_MODEL = 'host-model'
+    HOST_PASSTHROUGTH = 'host-passthrougth'
+    CUSTOM = 'custom'
+    MAXIMUM = 'maximum'
+
+
+class DomainCapabilities:
+
+    def __init__(self, session: libvirt.virConnect):
+        self.session = session
+        self.domcaps = fromstring(
+            self.session.getDomainCapabilities())
+
+    @property
+    def arch(self):
+        return self.domcaps.xpath('/domainCapabilities/arch')[0].text
+
+    @property
+    def virttype(self):
+        return self.domcaps.xpath('/domainCapabilities/domain')[0].text
+
+    @property
+    def emulator(self):
+        return self.domcaps.xpath('/domainCapabilities/path')[0].text
+
+    @property
+    def machine(self):
+        return self.domcaps.xpath('/domainCapabilities/machine')[0].text
+
+    def best_cpu(self, mode: vCPUMode) -> str:
+        """
+        See https://libvirt.org/html/libvirt-libvirt-host.html
+        #virConnectBaselineHypervisorCPU
+        """
+        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.session.baselineHypervisorCPU(self.emulator,
+            self.arch, self.machine, self.virttype, [xmlcpus])
+        return textwrap.indent(xml, ' ' * 2)
+
+
+class vCPUTopology(UserDict):
+    """
+    CPU topology schema ``{'sockets': 1, 'cores': 4, 'threads': 1}``::
+
+        <topology sockets='1' dies='1' cores='4' threads='1'/>
+    """
+
+    def __init__(self, topology: dict):
+        super().__init__(self._validate(topology))
+
+    def _validate(self, topology: dict):
+        if isinstance(topology, dict):
+            if ['sockets', 'cores', 'threads'] != list(topology.keys()):
+                raise ValueError("Topology must have 'sockets', 'cores' "
+                                 "and 'threads' keys.")
+            for key in topology.keys():
+                if not isinstance(topology[key], int):
+                    raise TypeError(f"Key '{key}' must be 'int'")
+            return topology
+        raise TypeError("Topology must be a 'dict'")

node_agent/vm/installer.py

@@ -0,0 +1,94 @@
+import re
+
+import libvirt
+
+from ..utils.xml import Constructor
+from ..utils.mac import random_mac
+from .hardware import DomainCapabilities, vCPUMode, vCPUTopology, Boot
+
+
+class vCPUInfo:
+    pass
+
+class ImageVolume:
+    pass
+
+class CloudInitConfig:
+    pass
+
+class BootOrder:
+    pass
+
+class VirtualMachineInstaller:
+    def __init__(self, session: libvirt.virConnect):
+        self.session = session
+        self.info = {}
+
+    def install(
+        self,
+        name: str | None = None,
+        title: str | None = None,
+        description: str = '',
+        os: str | None = None,
+        image: ImageVolume | None = None,
+        volumes: list['VolumeInfo'] | None = None,
+        vcpus: int = 0,
+        vcpu_info: vCPUInfo | None = None,
+        vcpu_mode: vCPUMode | None = None,
+        vcpu_topology: vCPUTopology | None = None,
+        memory: int = 0,
+        boot: Boot = Boot.BIOS,
+        boot_menu: bool = False,
+        boot_order: BootOrder = ('cdrom', 'hd'),
+        cloud_init: CloudInitConfig | None = None):
+        """
+        Install virtual machine with passed parameters.
+        """
+        domcaps = DomainCapabilities(self.session.session)
+        name = self._validate_name(name)
+        if vcpu_topology is None:
+            vcpu_topology = vCPUTopology(
+                {'sockets': 1, 'cores': vcpus, 'threads': 1})
+        self._validate_topology(vcpus, vcpu_topology)
+        if vcpu_info is None:
+            if not vcpu_mode:
+                vcpu_mode = vCPUMode.CUSTOM.value
+            xml_cpu = domcaps.best_cpu(vcpu_mode)
+        else:
+            raise NotImplementedError('Custom CPU not implemented')
+        xml_domain = Constructor().gen_domain_xml(
+            name=name,
+            title=title if title else name,
+            desc=description if description else '',
+            vcpus=vcpus,
+            memory=memory,
+            domain_type='hvm',
+            machine=domcaps.machine,
+            arch=domcaps.arch,
+            boot_order=('cdrom', 'hd'),
+            cpu=xml_cpu,
+            mac=random_mac()
+        )
+        return xml_domain
+
+    def _validate_name(self, name):
+        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 _validate_topology(self, vcpus, topology):
+        sockets = topology['sockets']
+        cores = topology['cores']
+        threads = topology['threads']
+        if sockets * cores * threads == vcpus:
+            return
+        raise ValueError("CPU topology must match the number of 'vcpus'")
+
+    def _define(self, xml: str):
+        self.session.defineXML(xml)

node_agent/vm/virtual_machine.py

@@ -13,7 +13,7 @@ class VirtualMachine(VirtualMachineBase):
 
     @property
     def name(self):
-        return self.domname
+        return self.domain_name
 
     @property
     def status(self) -> str:
@@ -27,7 +27,7 @@ class VirtualMachine(VirtualMachineBase):
             state = self.domain.state()[0]
         except libvirt.libvirtError as err:
             raise VMError(
-                f'Cannot fetch VM status vm={self.domname}: {err}') from err
+                f'Cannot fetch VM status vm={self.domain_name}: {err}') from err
         STATES = {
             libvirt.VIR_DOMAIN_NOSTATE: 'nostate',
             libvirt.VIR_DOMAIN_RUNNING: 'running',
@@ -57,20 +57,21 @@ class VirtualMachine(VirtualMachineBase):
             return False
         except libvirt.libvirtError as err:
             raise VMError(
-                f'Cannot get autostart status vm={self.domname}: {err}'
+                f'Cannot get autostart status vm={self.domain_name}: {err}'
             ) from err
 
     def start(self) -> None:
         """Start defined VM."""
-        logger.info('Starting VM: vm=%s', self.domname)
+        logger.info('Starting VM: vm=%s', self.domain_name)
         if self.is_running:
-            logger.debug('VM vm=%s is already started, nothing to do',
-                         self.domname)
+            logger.warning('VM vm=%s is already started, nothing to do',
+                         self.domain_name)
             return
         try:
             self.domain.create()
         except libvirt.libvirtError as err:
-            raise VMError(f'Cannot start vm={self.domname}: {err}') from err
+            raise VMError(
+                f'Cannot start vm={self.domain_name}: {err}') from err
 
     def shutdown(self, mode: str | None = None) -> None:
         """
@@ -78,7 +79,7 @@ class VirtualMachine(VirtualMachineBase):
         * GUEST_AGENT - use guest agent
         * NORMAL - use method choosen by hypervisor to shutdown machine
         * SIGTERM - send SIGTERM to QEMU process, destroy machine gracefully
-        * SIGKILL - send SIGKILL, this option may corrupt guest data!
+        * SIGKILL - send SIGKILL to QEMU process. May corrupt guest data!
         If mode is not passed use 'NORMAL' mode.
         """
         MODES = {
@@ -90,7 +91,7 @@ class VirtualMachine(VirtualMachineBase):
         if mode is None:
             mode = 'NORMAL'
         if not isinstance(mode, str):
-            raise ValueError(f'Mode must be a string, not {type(mode)}')
+            raise ValueError(f"Mode must be a 'str', not {type(mode)}")
         if mode.upper() not in MODES:
             raise ValueError(f"Unsupported mode: '{mode}'")
         try:
@@ -99,7 +100,7 @@ class VirtualMachine(VirtualMachineBase):
             elif mode in ['SIGTERM', 'SIGKILL']:
                 self.domain.destroyFlags(flags=MODES.get(mode))
         except libvirt.libvirtError as err:
-            raise VMError(f'Cannot shutdown vm={self.domname} with '
+            raise VMError(f'Cannot shutdown vm={self.domain_name} with '
                           f'mode={mode}: {err}') from err
 
     def reset(self) -> None:
@@ -116,16 +117,18 @@ class VirtualMachine(VirtualMachineBase):
         try:
             self.domain.reset()
         except libvirt.libvirtError as err:
-            raise VMError(f'Cannot reset vm={self.domname}: {err}') from err
+            raise VMError(
+                f'Cannot reset vm={self.domain_name}: {err}') from err
 
     def reboot(self) -> None:
         """Send ACPI signal to guest OS to reboot. OS may ignore this."""
         try:
             self.domain.reboot()
         except libvirt.libvirtError as err:
-            raise VMError(f'Cannot reboot vm={self.domname}: {err}') from err
+            raise VMError(
+                f'Cannot reboot vm={self.domain_name}: {err}') from err
 
-    def autostart(self, enable: bool) -> None:
+    def set_autostart(self, enable: bool) -> None:
         """
         Configure VM to be automatically started when the host machine boots.
         """
@@ -136,13 +139,57 @@ class VirtualMachine(VirtualMachineBase):
         try:
             self.domain.setAutostart(autostart_flag)
         except libvirt.libvirtError as err:
-            raise VMError(f'Cannot set autostart vm={self.domname} '
+            raise VMError(f'Cannot set autostart vm={self.domain_name} '
                           f'autostart={autostart_flag}: {err}') from err
 
-    def set_vcpus(self, count: int):
+    def set_vcpus(self, nvcpus: int, hotplug: bool = False):
+        """
+        Set vCPUs for VM. If `hotplug` is True set vCPUs on running VM.
+        If VM is not running set `hotplug` to False. If `hotplug` is True
+        and VM is not currently running vCPUs will set in config and will
+        applied when machine boot.
+
+        NB: Note that if this call is executed before the guest has
+        finished booting, the guest may fail to process the change.
+        """
+        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 +
+                     libvirt.VIR_DOMAIN_AFFECT_CONFIG)
+        else:
+            flags = libvirt.VIR_DOMAIN_AFFECT_CONFIG
+        try:
+            self.domain.setVcpusFlags(nvcpus, flags=flags)
+        except libvirt.libvirtError as err:
+            raise VMError(
+                f'Cannot set vCPUs for vm={self.domain_name}: {err}') from err
+
+    def set_memory(self, memory: int, hotplug: bool = False):
+        """
+        Set momory for VM. `memory` must be passed in mebibytes. Internally
+        converted to kibibytes. If `hotplug` is True set memory for running
+        VM, else set memory in config and will applied when machine boot.
+        If `hotplug` is True and machine is not currently running set memory
+        in config.
+        """
+        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 +
+                     libvirt.VIR_DOMAIN_AFFECT_CONFIG)
+        else:
+            flags = libvirt.VIR_DOMAIN_AFFECT_CONFIG
+        try:
+            self.domain.setVcpusFlags(memory * 1024, flags=flags)
+        except libvirt.libvirtError as err:
+            raise VMError(
+                f'Cannot set memory for vm={self.domain_name}: {err}') from err
+
+    def attach_device(self, device: str):
         pass
 
-    def set_ram(self, count: int):
+    def detach_device(self, device: str):
         pass
 
     def list_ssh_keys(self, user: str):
@@ -156,3 +203,11 @@ class VirtualMachine(VirtualMachineBase):
 
     def set_user_password(self, user: str):
         pass
+
+    def dump_xml(self) -> str:
+        return self.domain.XMLDesc()
+
+    def delete(self, delete_volumes: bool = False):
+        """Undefine VM."""
+        self.shutdown(method='SIGTERM')
+        self.domain.undefine()