Merge "Make sure we can create an empty template"

heat/engine/cfn/template.py

@@ -53,12 +53,14 @@ class CfnTemplate(template.Template):
         else:
             default = {}
 
-        return self.t.get(section, default)
+        # if a section is None (empty yaml section) return {}
+        # to be consistent with an empty json section.
+        return self.t.get(section) or default
 
     def param_schemata(self):
-        params = self.t.get(self.PARAMETERS, {}).iteritems()
+        params = self.t.get(self.PARAMETERS) or {}
         return dict((name, parameters.Schema.from_dict(name, schema))
-                    for name, schema in params)
+                    for name, schema in params.iteritems())
 
     def parameters(self, stack_identifier, user_params):
         return parameters.Parameters(stack_identifier, self,
@@ -125,8 +127,9 @@ class CfnTemplate(template.Template):
                                                 description=description)
             return name, defn
 
-        resources = self.t.get(self.RESOURCES, {}).items()
-        return dict(rsrc_defn_item(name, data) for name, data in resources)
+        resources = self.t.get(self.RESOURCES) or {}
+        return dict(rsrc_defn_item(name, data)
+                    for name, data in resources.items())
 
     def add_resource(self, definition, name=None):
         if name is None:

heat/engine/hot/template.py

@@ -70,6 +70,8 @@ class HOTemplate(template.Template):
         else:
             default = {}
 
+        # if a section is None (empty yaml section) return {}
+        # to be consistent with an empty json section.
         the_section = self.t.get(section) or default
 
         # In some cases (e.g. parameters), also translate each entry of
@@ -212,8 +214,9 @@ class HOTemplate(template.Template):
                                                 update_policy)
             return name, defn
 
-        resources = self.t.get(self.RESOURCES, {}).items()
-        return dict(rsrc_defn_item(name, data) for name, data in resources)
+        resources = self.t.get(self.RESOURCES) or {}
+        return dict(rsrc_defn_item(name, data)
+                    for name, data in resources.items())
 
     def add_resource(self, definition, name=None):
         if name is None:

heat/engine/template.py

@@ -219,7 +219,7 @@ class Template(collections.Mapping):
 
         # check resources
         tmpl_resources = self[self.RESOURCES]
-        if not tmpl_resources:
+        if len(tmpl_resources) == 0:
             LOG.warn(_('Template does not contain any resources, so '
                        'the template would not really do anything when '
                        'being instantiated.'))

heat/tests/test_empty_stack.py

@@ -0,0 +1,75 @@
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from heat.common import template_format
+from heat.engine import parser
+from heat.engine import template
+from heat.tests import common
+from heat.tests import utils
+
+
+class StackTest(common.HeatTestCase):
+    def setUp(self):
+        super(StackTest, self).setUp()
+        self.username = 'parser_stack_test_user'
+        self.ctx = utils.dummy_context()
+
+    def _assert_can_create(self, templ):
+        stack = parser.Stack(self.ctx, 'update_stack_arn_test',
+                             template.Template(templ))
+        stack.store()
+        stack.create()
+        self.assertEqual((parser.Stack.CREATE, parser.Stack.COMPLETE),
+                         stack.state)
+
+    def test_heat_empty_json(self):
+        tmpl = {'HeatTemplateFormatVersion': '2012-12-12',
+                'Resources': {}, 'Parameters': {}, 'Outputs': {}}
+        self._assert_can_create(tmpl)
+
+    def test_cfn_empty_json(self):
+        tmpl = {'AWSTemplateFormatVersion': '2010-09-09',
+                'Resources': {}, 'Parameters': {}, 'Outputs': {}}
+        self._assert_can_create(tmpl)
+
+    def test_hot_empty_json(self):
+        tmpl = {'heat_template_version': '2013-05-23',
+                'resources': {}, 'parameters': {}, 'outputs': {}}
+        self._assert_can_create(tmpl)
+
+    def test_heat_empty_yaml(self):
+        t = template_format.parse('''
+HeatTemplateFormatVersion: 2012-12-12
+Parameters:
+Resources:
+Outputs:
+''')
+        self._assert_can_create(t)
+
+    def test_cfn_empty_yaml(self):
+        t = template_format.parse('''
+AWSTemplateFormatVersion: 2010-09-09
+Parameters:
+Resources:
+Outputs:
+''')
+        self._assert_can_create(t)
+
+    def test_hot_empty_yaml(self):
+        t = template_format.parse('''
+heat_template_version: 2013-05-23
+parameters:
+resources:
+outputs:
+''')
+        self._assert_can_create(t)

heat/tests/test_hot.py

@@ -123,6 +123,7 @@ class HOTemplateTest(HeatTestCase):
 
         self.assertIsNone(stack.parameters._validate_user_parameters())
         self.assertIsNone(stack.parameters._validate_tmpl_parameters())
+        self.assertIsNone(stack.validate())
 
     def test_translate_resources_good(self):
         """Test translation of resources into internal engine format."""

heat/tests/test_template.py

@@ -13,6 +13,7 @@
 #    under the License.
 
 from heat.common import exception
+from heat.common import template_format
 from heat.engine.cfn.template import CfnTemplate
 from heat.engine import plugin_manager
 from heat.engine import template
@@ -151,6 +152,17 @@ class TestTemplateValidate(HeatTestCase):
                                 tmpl.validate)
         self.assertIn('Parameteers', str(err))
 
+    def test_template_validate_cfn_empty(self):
+        t = template_format.parse('''
+AWSTemplateFormatVersion: 2010-09-09
+Parameters:
+Resources:
+Outputs:
+''')
+        tmpl = template.Template(t)
+        err = tmpl.validate()
+        self.assertIsNone(err)
+
     def test_template_validate_hot_good(self):
         t = {
             'heat_template_version': '2013-05-23',