DB query to get all resources by the root stack

To prevent a resource query for every nested stack during a
resource-list, there needs to be a way to fetch every resource in a
single query.

Change-Id: Ib05b2166d6c7584a844e1ab4a5dd6e35437c96c4
Related-Bug: #1578854

heat/db/api.py

@@ -129,6 +129,10 @@ def resource_get_all_active_by_stack(context, stack_id):
     return IMPL.resource_get_all_active_by_stack(context, stack_id)
 
 
+def resource_get_all_by_root_stack(context, stack_id, filters=None):
+    return IMPL.resource_get_all_by_root_stack(context, stack_id, filters)
+
+
 def resource_get_by_name_and_stack(context, resource_name, stack_id):
     return IMPL.resource_get_by_name_and_stack(context,
                                                resource_name, stack_id)

heat/db/sqlalchemy/api.py

@@ -373,6 +373,19 @@ def resource_get_all_active_by_stack(context, stack_id):
     return dict((res.id, res) for res in results)
 
 
+def resource_get_all_by_root_stack(context, stack_id, filters=None):
+    query = model_query(
+        context, models.Resource
+    ).filter_by(
+        root_stack_id=stack_id
+    ).options(orm.joinedload("data"))
+
+    query = db_filters.exact_filter(query, models.Resource, filters)
+    results = query.all()
+
+    return dict((res.id, res) for res in results)
+
+
 def stack_get_by_name_and_owner_id(context, stack_name, owner_id):
     query = soft_delete_aware_query(
         context, models.Stack

heat/objects/resource.py

@@ -138,6 +138,10 @@ class Resource(
     def get_all_by_stack(cls, context, stack_id, filters=None):
         resources_db = db_api.resource_get_all_by_stack(context, stack_id,
                                                         filters)
+        return cls._resources_to_dict(context, resources_db)
+
+    @classmethod
+    def _resources_to_dict(cls, context, resources_db):
         resources = [
             (
                 resource_name,
@@ -160,6 +164,14 @@ class Resource(
         ]
         return dict(resources)
 
+    @classmethod
+    def get_all_by_root_stack(cls, context, stack_id, filters):
+        resources_db = db_api.resource_get_all_by_root_stack(
+            context,
+            stack_id,
+            filters)
+        return cls._resources_to_dict(context, resources_db)
+
     @classmethod
     def get_by_name_and_stack(cls, context, resource_name, stack_id):
         resource_db = db_api.resource_get_by_name_and_stack(

heat/tests/db/test_sqlalchemy_api.py

@@ -2278,6 +2278,50 @@ class DBAPIResourceTest(common.HeatTestCase):
         for rsrc_id, res in resources.items():
             self.assertIn(res.name, ['res2', 'res3', 'res4', 'res5', 'res6'])
 
+    def test_resource_get_all_by_root_stack(self):
+        self.stack1 = create_stack(self.ctx, self.template, self.user_creds)
+        self.stack2 = create_stack(self.ctx, self.template, self.user_creds)
+
+        create_resource(self.ctx, self.stack, name='res1',
+                        root_stack_id=self.stack.id)
+        create_resource(self.ctx, self.stack, name='res2',
+                        root_stack_id=self.stack.id)
+        create_resource(self.ctx, self.stack, name='res3',
+                        root_stack_id=self.stack.id)
+        create_resource(self.ctx, self.stack1, name='res4',
+                        root_stack_id=self.stack.id)
+
+        # Test for all resources in a stack
+        resources = db_api.resource_get_all_by_root_stack(
+            self.ctx, self.stack.id)
+        self.assertEqual(4, len(resources))
+        resource_names = [r.name for r in resources.values()]
+        self.assertEqual(['res1', 'res2', 'res3', 'res4'],
+                         sorted(resource_names))
+
+        # Test for resources matching single entry
+        resources = db_api.resource_get_all_by_root_stack(
+            self.ctx, self.stack.id, filters=dict(name='res1'))
+        self.assertEqual(1, len(resources))
+        resource_names = [r.name for r in resources.values()]
+        self.assertEqual(['res1'], resource_names)
+        self.assertEqual(1, len(resources))
+
+        # Test for resources matching multi entry
+        resources = db_api.resource_get_all_by_root_stack(
+            self.ctx, self.stack.id, filters=dict(name=[
+                'res1',
+                'res2'
+            ])
+        )
+        self.assertEqual(2, len(resources))
+        resource_names = [r.name for r in resources.values()]
+        self.assertEqual(['res1', 'res2'],
+                         sorted(resource_names))
+
+        self.assertEqual({}, db_api.resource_get_all_by_root_stack(
+            self.ctx, self.stack2.id))
+
 
 class DBAPIStackLockTest(common.HeatTestCase):
     def setUp(self):