From 40a56ce05b185ae418d5b548e19577209dfe772f Mon Sep 17 00:00:00 2001
From: Dan Smith <dansmith@redhat.com>
Date: Thu, 11 Jan 2024 07:28:22 -0800
Subject: [PATCH] Catch ImageNotFound on snapshot failure

Right now we're logging this as an unexpected failure, complete with
full traceback. However, this is expected if an image is deleted
mid-snapshot, as is the case in one of our tempest tests.

Change-Id: I6eb76c0500c7940778b7a15ac5202659ef92a82a
---
 nova/tests/unit/virt/libvirt/test_driver.py | 30 +++++++++++++++++++++
 nova/virt/libvirt/driver.py                 |  9 +++++++
 2 files changed, 39 insertions(+)

diff --git a/nova/tests/unit/virt/libvirt/test_driver.py b/nova/tests/unit/virt/libvirt/test_driver.py
index 5afd87e08d07..8b3786f0bfd9 100644
--- a/nova/tests/unit/virt/libvirt/test_driver.py
+++ b/nova/tests/unit/virt/libvirt/test_driver.py
@@ -29337,6 +29337,36 @@ class LibvirtSnapshotTests(_BaseSnapshotTests):
         rbd.remove_snap.assert_called_with('c', 'd', ignore_errors=True,
                                            pool='b', force=True)
 
+    @mock.patch.object(libvirt_driver, 'LOG')
+    @mock.patch('nova.virt.libvirt.utils.get_disk_type_from_path',
+                new=mock.Mock(return_value='rbd'))
+    @mock.patch('nova.virt.libvirt.utils.find_disk',
+                new=mock.Mock(return_value=('rbd://some/fake/rbd/image',
+                                            'raw')))
+    @mock.patch.object(rbd_utils, 'RBDDriver')
+    @mock.patch.object(rbd_utils, 'rbd')
+    def test_raw_with_rbd_clone_fails_image_deleted(
+            self, mock_rbd, mock_driver, mock_log):
+        self.flags(images_type='rbd', group='libvirt')
+        rbd = mock_driver.return_value
+        rbd.parent_info = mock.Mock(return_value=['test-pool', '', ''])
+        rbd.parse_url = mock.Mock(return_value=['a', 'b', 'c', 'd'])
+        with mock.patch.object(self.image_service, 'update',
+                               side_effect=exception.ImageNotFound(
+                                    image_id=uuids.new_snapshot)):
+            self.assertRaises(exception.ImageNotFound, self._test_snapshot,
+                              disk_format='raw')
+        rbd.clone.assert_called_with(mock.ANY, mock.ANY, dest_pool='test-pool')
+        rbd.flatten.assert_called_with(mock.ANY, pool='test-pool')
+        # Ensure that the direct_snapshot attempt was cleaned up
+        rbd.remove_snap.assert_called_with('c', 'd', ignore_errors=True,
+                                           pool='b', force=True)
+        # Make sure we took the NotFound-specific error path, and thus just
+        # logged a warning, instead of the catch-all which logs exception.
+        mock_log.exception.assert_not_called()
+        mock_log.warning.assert_called_once_with(
+            'Failed to snapshot image because it was deleted')
+
     @mock.patch('nova.virt.libvirt.utils.get_disk_type_from_path',
                 new=mock.Mock(return_value='rbd'))
     @mock.patch('nova.virt.libvirt.utils.find_disk',
diff --git a/nova/virt/libvirt/driver.py b/nova/virt/libvirt/driver.py
index f56bc7d05735..a7db984ba425 100644
--- a/nova/virt/libvirt/driver.py
+++ b/nova/virt/libvirt/driver.py
@@ -3180,6 +3180,15 @@ class LibvirtDriver(driver.ComputeDriver):
                                                image_id,
                                                metadata,
                                                image_file)
+        except exception.ImageNotFound:
+            with excutils.save_and_reraise_exception():
+                LOG.warning("Failed to snapshot image because it was deleted")
+                failed_snap = metadata.pop('location', None)
+                if failed_snap:
+                    failed_snap = {'url': str(failed_snap)}
+                root_disk.cleanup_direct_snapshot(
+                        failed_snap, also_destroy_volume=True,
+                        ignore_errors=True)
         except Exception:
             with excutils.save_and_reraise_exception():
                 LOG.exception("Failed to snapshot image")