Merge "Update nova's copy of image metadata on rebuild"

nova/compute/api.py

@@ -1349,6 +1349,32 @@ class API(BaseAPI):
         if instance_type['root_gb'] < int(image.get('min_disk') or 0):
             raise exception.InstanceTypeDiskTooSmall()
 
+        def _reset_image_metadata():
+            """
+            Remove old image properties that we're storing as instance
+            system metadata.  These properties start with 'image_'.
+            Then add the properites for the new image.
+            """
+
+            # FIXME(comstud): There's a race condition here in that
+            # if the system_metadata for this instance is updated
+            # after we do the get and before we update.. those other
+            # updates will be lost. Since this problem exists in a lot
+            # of other places, I think it should be addressed in a DB
+            # layer overhaul.
+            sys_metadata = self.db.instance_system_metadata_get(context,
+                    instance['uuid'])
+            # Remove the old keys
+            for key in sys_metadata.keys():
+                if key.startswith('image_'):
+                    del sys_metadata[key]
+            # Add the new ones
+            for key, value in image['properties'].iteritems():
+                new_value = str(value)[:255]
+                sys_metadata['image_%s' % key] = new_value
+            self.db.instance_system_metadata_update(context,
+                    instance['uuid'], sys_metadata, True)
+
         self.update(context,
                     instance,
                     vm_state=vm_states.REBUILDING,
@@ -1359,6 +1385,11 @@ class API(BaseAPI):
                     progress=0,
                     **kwargs)
 
+        # On a rebuild, since we're potentially changing images, we need to
+        # wipe out the old image properties that we're storing as instance
+        # system metadata... and copy in the properties for the new image.
+        _reset_image_metadata()
+
         rebuild_params = {
             "new_pass": admin_password,
             "injected_files": files_to_inject,

nova/tests/test_compute.py

@@ -115,7 +115,7 @@ class BaseTestCase(test.TestCase):
         test_notifier.NOTIFICATIONS = []
 
         def fake_show(meh, context, id):
-            return {'id': 1, 'min_disk': None, 'min_ram': None,
+            return {'id': id, 'min_disk': None, 'min_ram': None,
                     'properties': {'kernel_id': 'fake_kernel_id',
                                    'ramdisk_id': 'fake_ramdisk_id',
                                    'something_else': 'meow'}}
@@ -2307,6 +2307,15 @@ class ComputeAPITestCase(BaseTestCase):
 
         instance = db.instance_get_by_uuid(self.context, instance_uuid)
         self.assertEqual(instance['task_state'], None)
+        # Set some image metadata that should get wiped out and reset
+        # as well as some other metadata that should be preserved.
+        db.instance_system_metadata_update(self.context, instance_uuid,
+                {'image_kernel_id': 'old-data',
+                 'image_ramdisk_id': 'old_data',
+                 'image_something_else': 'old-data',
+                 'image_should_remove': 'bye-bye',
+                 'preserved': 'preserve this!'},
+                True)
 
         # Make sure Compute API updates the image_ref before casting to
         # compute manager.
@@ -2327,7 +2336,13 @@ class ComputeAPITestCase(BaseTestCase):
 
         instance = db.instance_get_by_uuid(self.context, instance_uuid)
         self.assertEqual(instance['vm_state'], vm_states.REBUILDING)
-
+        sys_metadata = db.instance_system_metadata_get(self.context,
+                instance_uuid)
+        self.assertEqual(sys_metadata,
+                {'image_kernel_id': 'fake_kernel_id',
+                 'image_ramdisk_id': 'fake_ramdisk_id',
+                 'image_something_else': 'meow',
+                 'preserved': 'preserve this!'})
         db.instance_destroy(self.context, instance['id'])
 
     def test_reboot_soft(self):