Create instance in DB before block device mapping

Fixes lp 1019334

A recently added foreign key constraint on the the block_device_mapping
table causes boot-from-volume to fail, as the bdm is populated before the
instance DB entry is created.

This fix simply transposes the ordering to avoid breaking the constraint.

Change-Id: Ic62ea3ba000a2cdf58d2bd5bb17dde2b8cf340e4

1 files changed, 13 insertions, 4 deletions

diff --git a/nova/compute/api.py b/nova/compute/api.py
index 557dbb930..3fbaf12df 100644
--- a/nova/compute/api.py
+++ b/nova/compute/api.py
@@ -587,7 +587,6 @@ class API(base.Base):
         instance_uuid = instance['uuid']
         mappings = image['properties'].get('mappings', [])
         if mappings:
-            instance['shutdown_terminate'] = False
             self._update_image_block_device_mapping(elevated,
                     instance_type, instance_uuid, mappings)
 
@@ -595,10 +594,17 @@ class API(base.Base):
         for mapping in (image_bdm, block_device_mapping):
             if not mapping:
                 continue
-            instance['shutdown_terminate'] = False
             self._update_block_device_mapping(elevated,
                     instance_type, instance_uuid, mapping)
 
+    def _populate_instance_shutdown_terminate(self, instance, image,
+                                              block_device_mapping):
+        """Populate instance shutdown_terminate information."""
+        if (block_device_mapping or
+            image['properties'].get('mappings') or
+            image['properties'].get('block_device_mapping')):
+            instance['shutdown_terminate'] = False
+
     def _populate_instance_names(self, instance):
         """Populate instance display_name and hostname."""
         display_name = instance.get('display_name')
@@ -662,11 +668,14 @@ class API(base.Base):
 
         self._populate_instance_names(instance)
 
-        self._populate_instance_for_bdm(context, instance,
-                instance_type, image, block_device_mapping)
+        self._populate_instance_shutdown_terminate(instance, image,
+                                                   block_device_mapping)
 
         instance = self.db.instance_create(context, instance)
 
+        self._populate_instance_for_bdm(context, instance,
+                instance_type, image, block_device_mapping)
+
         # send a state update notification for the initial create to
         # show it going from non-existent to BUILDING
         notifications.send_update_with_states(context, instance, None,