Scan for output errors in functional tests

In _stack_output() look for unexpected "output_error" messages.
Fix a missing output in the template resource tests.

Change-Id: I71d5d7e5800d7503d9e6015f637fe7fef5d867fe

heat_integrationtests/common/test.py

@@ -175,10 +175,18 @@ class HeatIntegrationTest(testscenarios.WithScenarios,
                 return net
 
     @staticmethod
-    def _stack_output(stack, output_key):
+    def _stack_output(stack, output_key, validate_errors=True):
         """Return a stack output value for a given key."""
-        return next((o['output_value'] for o in stack.outputs
-                    if o['output_key'] == output_key), None)
+        value = None
+        for o in stack.outputs:
+            if validate_errors and 'output_error' in o:
+                # scan for errors in the stack output.
+                raise ValueError(
+                    'Unexpected output errors in %s : %s' % (
+                        output_key, o['output_error']))
+            if o['output_key'] == output_key:
+                value = o['output_value']
+        return value
 
     def _ping_ip_address(self, ip_address, should_succeed=True):
         cmd = ['ping', '-c1', '-w1', ip_address]

heat_integrationtests/functional/test_resource_group.py

@@ -244,14 +244,14 @@ resources:
 
         env = {'resource_registry':
                {'My::RandomString': 'OS::Heat::RandomString'}}
-        template_one = self.template.replace("count: 0", "count: 1")
+        template_one = self.template.replace("count: 0", "count: 2")
         stack_identifier = self.stack_create(template=template_one,
                                              environment=env)
         self.assertEqual({u'random_group': u'OS::Heat::ResourceGroup'},
                          self.list_resources(stack_identifier))
 
         initial_nested_ident = self._group_nested_identifier(stack_identifier)
-        self.assertEqual({'0': 'My::RandomString'},
+        self.assertEqual({'0': 'My::RandomString', '1': 'My::RandomString'},
                          self.list_resources(initial_nested_ident))
         # get the output
         stack0 = self.client.stacks.get(stack_identifier)
@@ -301,7 +301,7 @@ outputs:
         env = {'resource_registry':
                {'My::RandomString': 'my_random.yaml'}}
 
-        template_one = self.template.replace("count: 0", "count: 1")
+        template_one = self.template.replace("count: 0", "count: 2")
         stack_identifier = self.stack_create(template=template_one,
                                              environment=env,
                                              files=files1)
@@ -309,7 +309,7 @@ outputs:
                          self.list_resources(stack_identifier))
 
         initial_nested_ident = self._group_nested_identifier(stack_identifier)
-        self.assertEqual({'0': 'My::RandomString'},
+        self.assertEqual({'0': 'My::RandomString', '1': 'My::RandomString'},
                          self.list_resources(initial_nested_ident))
         # get the output
         stack0 = self.client.stacks.get(stack_identifier)

heat_integrationtests/functional/test_template_resource.py

@@ -180,6 +180,9 @@ heat_template_version: 2014-10-16
 resources:
   secret1:
     type: OS::Heat::RandomString
+outputs:
+  nested_str:
+    value: {get_attr: [secret1, value]}
 '''
         stack_identifier = self.stack_create(
             template=self.main_templ,