python-compute/compute/storage/volume.py
2023-12-13 01:42:50 +03:00

113 lines
3.3 KiB
Python

# This file is part of Compute
#
# Compute 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.
#
# Compute 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 Compute. If not, see <http://www.gnu.org/licenses/>.
"""Manage storage volumes."""
from dataclasses import dataclass
from pathlib import Path
from time import time
import libvirt
from lxml import etree
from lxml.builder import E
from compute.abstract import EntityConfig
from compute.utils import units
@dataclass
class VolumeConfig(EntityConfig):
"""
Storage volume XML config builder.
Generate XML config for creating a volume in a libvirt
storage pool.
"""
name: str
path: str
capacity: int
def to_xml(self) -> str:
"""Return XML config for libvirt."""
unixtime = str(int(time()))
xml = E.volume(type='file')
xml.append(E.name(self.name))
xml.append(E.key(self.path))
xml.append(E.source())
xml.append(E.capacity(str(self.capacity), unit='bytes'))
xml.append(E.allocation('0'))
xml.append(
E.target(
E.path(self.path),
E.format(type='qcow2'),
E.timestamps(
E.atime(unixtime), E.mtime(unixtime), E.ctime(unixtime)
),
E.compat('1.1'),
E.features(E.lazy_refcounts()),
)
)
return etree.tostring(xml, encoding='unicode', pretty_print=True)
class Volume:
"""Storage volume manipulating class."""
def __init__(
self, pool: libvirt.virStoragePool, vol: libvirt.virStorageVol
):
"""
Initialise Volume.
:param pool: libvirt virStoragePool object
:param vol: libvirt virStorageVol object
"""
self.pool = pool
self.pool_name = pool.name()
self.vol = vol
self.name = vol.name()
self.path = Path(vol.path())
def dump_xml(self) -> str:
"""Return volume XML description as string."""
return self.vol.XMLDesc()
def clone(self, vol_conf: VolumeConfig) -> None:
"""
Make a copy of volume to the same storage pool.
:param vol_info VolumeInfo: New storage volume dataclass object
"""
self.pool.createXMLFrom(
vol_conf.to_xml(),
self.vol,
flags=libvirt.VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA,
)
def resize(self, capacity: int, unit: units.DataUnit) -> None:
"""
Resize volume.
:param capacity int: Volume new capacity.
:param unit DataUnit: Data unit. Internally converts into bytes.
"""
# TODO @ge: Check actual volume size before resize
self.vol.resize(units.to_bytes(capacity, unit=unit))
def delete(self) -> None:
"""Delete volume from storage pool."""
self.vol.delete()