Add link to a resource's nested stack

When viewing a resource, it's valuable to know whether the resource is a
nested stack with additional resources attached to it.  This change
provides a new 'nested' link in the links section of a resource, which
points to the nested stack.

Co-Authored-By: Richard Lee <rblee88@gmail.com>
Implements: blueprint nested-stack-link
Change-Id: Ibc8768d2be8f1dae9a60d3818ae9f56c27bbdc9b

heat/api/openstack/v1/resources.py

@@ -30,11 +30,19 @@ def format_resource(req, res, keys=[]):
 
         if key == engine_api.RES_ID:
             identity = identifier.ResourceIdentifier(**value)
-            yield ('links', [util.make_link(req, identity),
-                             util.make_link(req, identity.stack(), 'stack')])
+            links = [util.make_link(req, identity),
+                     util.make_link(req, identity.stack(), 'stack')]
+
+            nested_id = res.get(engine_api.RES_NESTED_STACK_ID)
+            if nested_id:
+                nested_identity = identifier.HeatIdentifier(**nested_id)
+                links.append(util.make_link(req, nested_identity, 'nested'))
+
+            yield ('links', links)
         elif (key == engine_api.RES_STACK_NAME or
               key == engine_api.RES_STACK_ID or
-              key == engine_api.RES_ACTION):
+              key == engine_api.RES_ACTION or
+              key == engine_api.RES_NESTED_STACK_ID):
             return
         elif (key == engine_api.RES_METADATA):
             return

heat/engine/api.py

@@ -130,6 +130,9 @@ def format_stack_resource(resource, detail=True):
         api.RES_REQUIRED_BY: resource.required_by(),
     }
 
+    if hasattr(resource, 'nested') and callable(resource.nested):
+        res[api.RES_NESTED_STACK_ID] = dict(resource.nested().identifier())
+
     if detail:
         res[api.RES_DESCRIPTION] = resource.parsed_template('Description', '')
         res[api.RES_METADATA] = resource.metadata

heat/rpc/api.py

@@ -50,13 +50,13 @@ RES_KEYS = (
     RES_NAME, RES_PHYSICAL_ID, RES_METADATA,
     RES_ACTION, RES_STATUS, RES_STATUS_DATA,
     RES_TYPE, RES_ID, RES_STACK_ID, RES_STACK_NAME,
-    RES_REQUIRED_BY,
+    RES_REQUIRED_BY, RES_NESTED_STACK_ID,
 ) = (
     'description', 'updated_time',
     'resource_name', 'physical_resource_id', 'metadata',
     'resource_action', 'resource_status', 'resource_status_reason',
     'resource_type', 'resource_identity', STACK_ID, STACK_NAME,
-    'required_by',
+    'required_by', 'nested_stack_id',
 )
 
 RES_SCHEMA_KEYS = (

heat/tests/test_api_openstack_v1.py

@@ -1851,6 +1851,58 @@ class ResourceControllerTest(ControllerTest, HeatTestCase):
         self.assertEqual(expected, result)
         self.m.VerifyAll()
 
+    def test_show_with_nested_stack(self, mock_enforce):
+        self._mock_enforce_setup(mock_enforce, 'show', True)
+        res_name = 'WikiDatabase'
+        stack_identity = identifier.HeatIdentifier(self.tenant,
+                                                   'wordpress', '6')
+        res_identity = identifier.ResourceIdentifier(resource_name=res_name,
+                                                     **stack_identity)
+        nested_stack_identity = identifier.HeatIdentifier(self.tenant,
+                                                          'nested', 'some_id')
+
+        req = self._get(stack_identity._tenant_path())
+
+        engine_resp = {
+            u'description': u'',
+            u'resource_identity': dict(res_identity),
+            u'stack_name': stack_identity.stack_name,
+            u'resource_name': res_name,
+            u'resource_status_reason': None,
+            u'updated_time': u'2012-07-23T13:06:00Z',
+            u'stack_identity': dict(stack_identity),
+            u'resource_action': u'CREATE',
+            u'resource_status': u'COMPLETE',
+            u'physical_resource_id':
+            u'a3455d8c-9f88-404d-a85b-5315293e67de',
+            u'resource_type': u'AWS::EC2::Instance',
+            u'metadata': {u'ensureRunning': u'true'},
+            u'nested_stack_id': dict(nested_stack_identity)
+        }
+        self.m.StubOutWithMock(rpc, 'call')
+        rpc.call(req.context, self.topic,
+                 {'namespace': None,
+                  'method': 'describe_stack_resource',
+                  'args': {'stack_identity': stack_identity,
+                           'resource_name': res_name},
+                  'version': self.api_version},
+                 None).AndReturn(engine_resp)
+        self.m.ReplayAll()
+
+        result = self.controller.show(req, tenant_id=self.tenant,
+                                      stack_name=stack_identity.stack_name,
+                                      stack_id=stack_identity.stack_id,
+                                      resource_name=res_name)
+
+        expected = [{'href': self._url(res_identity), 'rel': 'self'},
+                    {'href': self._url(stack_identity), 'rel': 'stack'},
+                    {'href': self._url(nested_stack_identity), 'rel': 'nested'}
+                    ]
+
+        self.assertEqual(expected, result['resource']['links'])
+        self.assertIsNone(result.get(rpc_api.RES_NESTED_STACK_ID))
+        self.m.VerifyAll()
+
     def test_show_nonexist(self, mock_enforce):
         self._mock_enforce_setup(mock_enforce, 'show', True)
         res_name = 'WikiDatabase'

heat/tests/test_engine_api_utils.py

@@ -159,6 +159,15 @@ class FormatTest(HeatTestCase):
         formatted = api.format_stack_resource(res, False)
         self.assertEqual(resource_keys, set(formatted.keys()))
 
+    def test_format_stack_resource_with_nested_stack(self):
+        res = self.stack['generic1']
+        nested_id = {'foo': 'bar'}
+        res.nested = mock.Mock()
+        res.nested.return_value.identifier.return_value = nested_id
+
+        formatted = api.format_stack_resource(res, False)
+        self.assertEqual(nested_id, formatted[rpc_api.RES_NESTED_STACK_ID])
+
     def test_format_stack_resource_required_by(self):
         res1 = api.format_stack_resource(self.stack['generic1'])
         res2 = api.format_stack_resource(self.stack['generic2'])