some updates

computelib/volume/__init__.py

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+from .storage_pool import StoragePool
+from .volume import DiskInfo, Volume, VolumeInfo

computelib/volume/storage_pool.py

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+import logging
+from collections import namedtuple
+
+import libvirt
+from lxml import etree
+
+from ..exceptions import StoragePoolError
+from .volume import Volume, VolumeInfo
+
+
+logger = logging.getLogger(__name__)
+
+
+class StoragePool:
+    def __init__(self, pool: libvirt.virStoragePool):
+        self.pool = pool
+
+    @property
+    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 refresh(self) -> None:
+        self.pool.refresh()
+
+    def create_volume(self, vol_info: VolumeInfo) -> Volume:
+        """
+        Create storage volume and return Volume instance.
+        """
+        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('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 or
+                    err.get_error_code() == libvirt.VIR_ERR_NO_STORAGE_VOL):
+                logger.error(err.get_error_message())
+                return None
+            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

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+from dataclasses import dataclass
+from time import time
+
+import libvirt
+from lxml import etree
+from lxml.builder import E
+
+
+@dataclass
+class VolumeInfo:
+    name: str
+    path: str
+    capacity: int
+
+    def to_xml(self) -> str:
+        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 * 1024 * 1024), 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)
+
+
+@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:
+    def __init__(self, pool: libvirt.virStoragePool,
+                 vol: libvirt.virStorageVol):
+        self.pool = pool
+        self.vol = vol
+
+    @property
+    def name(self) -> str:
+        return self.vol.name()
+
+    @property
+    def path(self) -> str:
+        return self.vol.path()
+
+    def dump_xml(self) -> str:
+        return self.vol.XMLDesc()
+
+    def clone(self, vol_info: VolumeInfo) -> None:
+        self.pool.createXMLFrom(
+            vol_info.to_xml(),
+            self.vol,
+            flags=libvirt.VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA)
+
+    def resize(self, capacity: int):
+        """Resize volume to `capacity`. Unit is mebibyte."""
+        self.vol.resize(capacity * 1024 * 1024)
+
+    def delete(self) -> None:
+        self.vol.delete()