various improvements

compute/storage/pool.py

@@ -7,7 +7,7 @@ from typing import NamedTuple
 import libvirt
 from lxml import etree
 
-from compute.exceptions import StoragePoolError
+from compute.exceptions import StoragePoolError, VolumeNotFoundError
 
 from .volume import Volume, VolumeConfig
 
@@ -99,13 +99,8 @@ class StoragePool:
             vol = self.pool.storageVolLookupByName(name)
             return Volume(self.pool, vol)
         except libvirt.libvirtError as e:
-            # TODO @ge: Raise VolumeNotFoundError instead
-            if (
-                e.get_error_domain() == libvirt.VIR_FROM_STORAGE
-                or e.get_error_code() == libvirt.VIR_ERR_NO_STORAGE_VOL
-            ):
-                log.exception(e.get_error_message())
-                return None
+            if e.get_error_code() == libvirt.VIR_ERR_NO_STORAGE_VOL:
+                raise VolumeNotFoundError(name) from e
             log.exception('unexpected error from libvirt')
             raise StoragePoolError(e) from e
 

compute/storage/volume.py

@@ -56,15 +56,17 @@ class DiskConfig:
     to compute instances.
     """
 
+    disk_type: str
+    source: str | Path
     target: str
-    path: str
     readonly: bool = False
 
     def to_xml(self) -> str:
         """Return XML config for libvirt."""
-        xml = E.disk(type='file', device='disk')
+        xml = E.disk(type=self.disk_type, device='disk')
         xml.append(E.driver(name='qemu', type='qcow2', cache='writethrough'))
-        xml.append(E.source(file=self.path))
+        if self.disk_type == 'file':
+            xml.append(E.source(file=str(self.source)))
         xml.append(E.target(dev=self.target, bus='virtio'))
         if self.readonly:
             xml.append(E.readonly())