From fcc17a6b09cbcfaa8aa9db2ee5d187de7f7649aa Mon Sep 17 00:00:00 2001
From: Haruka Tanizawa <h-tanizawa@intellilink.co.jp>
Date: Fri, 25 Apr 2014 11:41:40 +0900
Subject: [PATCH] Ensure metadata is saved before updating volume status

This patch ensures the volume metadata is saved to
the snapshot metadata before updating the status
of the snapshot to be available.

Change-Id: Iada010520dc3c086fcd410a6c7fd152cf4a31561
Closes-Bug: #1310991
---
 cinder/tests/test_volume.py | 84 +++++++++++++++++++++++++++++++++++++
 cinder/volume/manager.py    | 12 ++++--
 2 files changed, 92 insertions(+), 4 deletions(-)

diff --git a/cinder/tests/test_volume.py b/cinder/tests/test_volume.py
index a0016af73..0fb31667f 100644
--- a/cinder/tests/test_volume.py
+++ b/cinder/tests/test_volume.py
@@ -1688,6 +1688,90 @@ class VolumeTestCase(BaseVolumeTestCase):
         db.snapshot_destroy(self.context, snapshot_ref['id'])
         db.volume_destroy(self.context, volume['id'])
 
+    def test_create_snapshot_from_bootable_volume(self):
+        """Test create snapshot from bootable volume."""
+        # create bootable volume from image
+        volume = self._create_volume_from_image()
+        volume_id = volume['id']
+        self.assertEqual(volume['status'], 'available')
+        self.assertEqual(volume['bootable'], True)
+
+        # get volume's volume_glance_metadata
+        ctxt = context.get_admin_context()
+        vol_glance_meta = db.volume_glance_metadata_get(ctxt, volume_id)
+        self.assertTrue(vol_glance_meta)
+
+        # create snapshot from bootable volume
+        snap_id = self._create_snapshot(volume_id)['id']
+        self.volume.create_snapshot(ctxt, volume_id, snap_id)
+
+        # get snapshot's volume_glance_metadata
+        snap_glance_meta = db.volume_snapshot_glance_metadata_get(
+            ctxt, snap_id)
+        self.assertTrue(snap_glance_meta)
+
+        # ensure that volume's glance metadata is copied
+        # to snapshot's glance metadata
+        self.assertEqual(len(vol_glance_meta), len(snap_glance_meta))
+        vol_glance_dict = dict((x.key, x.value) for x in vol_glance_meta)
+        snap_glance_dict = dict((x.key, x.value) for x in snap_glance_meta)
+        self.assertDictMatch(vol_glance_dict, snap_glance_dict)
+
+        # ensure that snapshot's status is changed to 'available'
+        snapshot_ref = db.snapshot_get(ctxt, snap_id)['status']
+        self.assertEqual('available', snapshot_ref)
+
+        # cleanup resource
+        db.snapshot_destroy(ctxt, snap_id)
+        db.volume_destroy(ctxt, volume_id)
+
+    def test_create_snapshot_from_bootable_volume_fail(self):
+        """Test create snapshot from bootable volume.
+
+        But it fails to volume_glance_metadata_copy_to_snapshot.
+        As a result, status of snapshot is changed to ERROR.
+        """
+        # create bootable volume from image
+        volume = self._create_volume_from_image()
+        volume_id = volume['id']
+        self.assertEqual(volume['status'], 'available')
+        self.assertEqual(volume['bootable'], True)
+
+        # get volume's volume_glance_metadata
+        ctxt = context.get_admin_context()
+        vol_glance_meta = db.volume_glance_metadata_get(ctxt, volume_id)
+        self.assertTrue(vol_glance_meta)
+        snap = self._create_snapshot(volume_id)
+        snap_id = snap['id']
+        snap_stat = snap['status']
+        self.assertTrue(snap_id)
+        self.assertTrue(snap_stat)
+
+        # set to return DB exception
+        with mock.patch.object(db, 'volume_glance_metadata_copy_to_snapshot')\
+                as mock_db:
+            mock_db.side_effect = exception.MetadataCopyFailure(
+                reason="Because of DB service down.")
+            # create snapshot from bootable volume
+            self.assertRaises(exception.MetadataCopyFailure,
+                              self.volume.create_snapshot,
+                              ctxt,
+                              volume_id,
+                              snap_id)
+
+        # get snapshot's volume_glance_metadata
+        self.assertRaises(exception.GlanceMetadataNotFound,
+                          db.volume_snapshot_glance_metadata_get,
+                          ctxt, snap_id)
+
+        # ensure that status of snapshot is 'error'
+        snapshot_ref = db.snapshot_get(ctxt, snap_id)['status']
+        self.assertEqual('error', snapshot_ref)
+
+        # cleanup resource
+        db.snapshot_destroy(ctxt, snap_id)
+        db.volume_destroy(ctxt, volume_id)
+
     def test_delete_busy_snapshot(self):
         """Test snapshot can be created and deleted."""
 
diff --git a/cinder/volume/manager.py b/cinder/volume/manager.py
index 32fbfa517..1c3c34767 100644
--- a/cinder/volume/manager.py
+++ b/cinder/volume/manager.py
@@ -455,10 +455,6 @@ class VolumeManager(manager.SchedulerDependentManager):
                                         snapshot_ref['id'],
                                         {'status': 'error'})
 
-        self.db.snapshot_update(context,
-                                snapshot_ref['id'], {'status': 'available',
-                                                     'progress': '100%'})
-
         vol_ref = self.db.volume_get(context, volume_id)
         if vol_ref.bootable:
             try:
@@ -470,7 +466,15 @@ class VolumeManager(manager.SchedulerDependentManager):
                                 " %(volume_id)s metadata") %
                               {'volume_id': volume_id,
                                'snapshot_id': snapshot_id})
+                self.db.snapshot_update(context,
+                                        snapshot_ref['id'],
+                                        {'status': 'error'})
                 raise exception.MetadataCopyFailure(reason=ex)
+
+        self.db.snapshot_update(context,
+                                snapshot_ref['id'], {'status': 'available',
+                                                     'progress': '100%'})
+
         LOG.info(_("snapshot %s: created successfully"), snapshot_ref['id'])
         self._notify_about_snapshot_usage(context, snapshot_ref, "create.end")
         return snapshot_id
-- 
2.45.2