From 8843e7490b4ca4da6e5155c730600f44628b3abf Mon Sep 17 00:00:00 2001
From: Zane Bitter <zbitter@redhat.com>
Date: Fri, 31 May 2013 12:39:08 +0200
Subject: [PATCH] Create nested stacks in parallel

Use check_create_complete() to advance the nested stack creation, so that
it can occur in parallel with other resources in the parent stack.

Implements blueprint concurrent-resource-scheduling

Change-Id: I841b4c93b257409eecd0d2a43b35d9bee114ab87
---
 heat/engine/resources/dbinstance.py   |  2 +-
 heat/engine/resources/loadbalancer.py |  2 +-
 heat/engine/resources/stack.py        |  6 +++---
 heat/engine/stack_resource.py         | 16 +++++++++++++---
 heat/tests/test_dbinstance.py         |  2 ++
 heat/tests/test_nested_stack.py       |  3 ++-
 6 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/heat/engine/resources/dbinstance.py b/heat/engine/resources/dbinstance.py
index 567bc1e0..0bfd4d88 100644
--- a/heat/engine/resources/dbinstance.py
+++ b/heat/engine/resources/dbinstance.py
@@ -214,7 +214,7 @@ class DBInstance(stack_resource.StackResource):
 
     def handle_create(self):
         templ = template_format.parse(mysql_template)
-        self.create_with_template(templ, self._params())
+        return self.create_with_template(templ, self._params())
 
     def handle_delete(self):
         self.delete_nested()
diff --git a/heat/engine/resources/loadbalancer.py b/heat/engine/resources/loadbalancer.py
index 9c93224c..4e8fd180 100644
--- a/heat/engine/resources/loadbalancer.py
+++ b/heat/engine/resources/loadbalancer.py
@@ -331,7 +331,7 @@ class LoadBalancer(stack_resource.StackResource):
         # total hack - probably need an admin key here.
         param = self.stack.resolve_static_data({'KeyName': {'Ref': 'KeyName'}})
 
-        self.create_with_template(templ, param)
+        return self.create_with_template(templ, param)
 
     def handle_delete(self):
         self.delete_nested()
diff --git a/heat/engine/resources/stack.py b/heat/engine/resources/stack.py
index f4456575..c745c1f4 100644
--- a/heat/engine/resources/stack.py
+++ b/heat/engine/resources/stack.py
@@ -42,9 +42,9 @@ class NestedStack(stack_resource.StackResource):
         template_data = urlfetch.get(self.properties[PROP_TEMPLATE_URL])
         template = template_format.parse(template_data)
 
-        self.create_with_template(template,
-                                  self.properties[PROP_PARAMETERS],
-                                  self.properties[PROP_TIMEOUT_MINS])
+        return self.create_with_template(template,
+                                         self.properties[PROP_PARAMETERS],
+                                         self.properties[PROP_TIMEOUT_MINS])
 
     def handle_delete(self):
         self.delete_nested()
diff --git a/heat/engine/stack_resource.py b/heat/engine/stack_resource.py
index 2040e73f..507c0fd7 100644
--- a/heat/engine/stack_resource.py
+++ b/heat/engine/stack_resource.py
@@ -16,6 +16,7 @@
 from heat.common import exception
 from heat.engine import resource
 from heat.engine import parser
+from heat.engine import scheduler
 
 from heat.openstack.common import log as logging
 
@@ -65,9 +66,18 @@ class StackResource(resource.Resource):
 
         nested_id = self._nested.store(self.stack)
         self.resource_id_set(nested_id)
-        self._nested.create()
-        if self._nested.state != self._nested.CREATE_COMPLETE:
-            raise exception.Error(self._nested.state_description)
+
+        stack_creator = scheduler.TaskRunner(self._nested.create_task)
+        stack_creator.start(timeout=self._nested.timeout_secs())
+        return stack_creator
+
+    def check_create_complete(self, stack_creator):
+        done = stack_creator.step()
+        if done:
+            if self._nested.state != self._nested.CREATE_COMPLETE:
+                raise exception.Error(self._nested.state_description)
+
+        return done
 
     def delete_nested(self):
         '''
diff --git a/heat/tests/test_dbinstance.py b/heat/tests/test_dbinstance.py
index 0a5728d9..1b516673 100644
--- a/heat/tests/test_dbinstance.py
+++ b/heat/tests/test_dbinstance.py
@@ -58,6 +58,7 @@ class DBInstanceTest(HeatTestCase):
         super(DBInstanceTest, self).setUp()
         setup_dummy_db()
         self.m.StubOutWithMock(dbi.DBInstance, 'create_with_template')
+        self.m.StubOutWithMock(dbi.DBInstance, 'check_create_complete')
         self.m.StubOutWithMock(dbi.DBInstance, 'nested')
 
     def create_dbinstance(self, t, stack, resource_name):
@@ -89,6 +90,7 @@ class DBInstanceTest(HeatTestCase):
 
         dbi.DBInstance.create_with_template(mox.IgnoreArg(),
                                             params).AndReturn(None)
+        dbi.DBInstance.check_create_complete(mox.IgnoreArg()).AndReturn(True)
 
         fn = FakeNested()
 
diff --git a/heat/tests/test_nested_stack.py b/heat/tests/test_nested_stack.py
index 753b214a..83f46de8 100644
--- a/heat/tests/test_nested_stack.py
+++ b/heat/tests/test_nested_stack.py
@@ -50,7 +50,8 @@ Outputs:
     def create_stack(self, template):
         t = template_format.parse(template)
         stack = self.parse_stack(t)
-        self.assertEqual(None, stack.create())
+        stack.create()
+        self.assertEqual(stack.state, stack.CREATE_COMPLETE)
         return stack
 
     def parse_stack(self, t):
-- 
2.45.2