Migrate stacks from legacy to convergence engine

Run `heat-manage migrate-convergence-1 <stack_id>` to migrate
legacy stack to convergence engine.

Heat engine is used for doing migration i.e. migration can't
be done offline.

Change-Id: Ie7c2498b37937438f16d154b154b3a6ecbf9ff74
Implements-bp: convergence-migrate-stack

1 files changed, 11 insertions, 2 deletions

diff --git a/heat/objects/stack.py b/heat/objects/stack.py
index ee19cf2b2..65280fca8 100644
--- a/heat/objects/stack.py
+++ b/heat/objects/stack.py
@@ -15,10 +15,9 @@
 
 """Stack object."""
 
-import six
-
 from oslo_versionedobjects import base
 from oslo_versionedobjects import fields
+import six
 
 from heat.common import exception
 from heat.common.i18n import _
@@ -146,6 +145,16 @@ class Stack(
                 pass
 
     @classmethod
+    def get_all_by_root_owner_id(cls, context, root_owner_id):
+        db_stacks = db_api.stack_get_all_by_root_owner_id(context,
+                                                          root_owner_id)
+        for db_stack in db_stacks:
+            try:
+                yield cls._from_db_object(context, cls(context), db_stack)
+            except exception.NotFound:
+                pass
+
+    @classmethod
     def count_all(cls, context, **kwargs):
         return db_api.stack_count_all(context, **kwargs)