Return Environment from validate_template

This is to enable preview of the merged environment
without merging the environment on the client side.

Related-Bug: #1635409
Change-Id: I7ec3af729a65164230153021f438bf226cc5e858

8 files changed, 183 insertions, 18 deletions

diff --git a/api-ref/source/v1/parameters.yaml b/api-ref/source/v1/parameters.yaml
index 7722b0f44..7c657efe7 100644
--- a/api-ref/source/v1/parameters.yaml
+++ b/api-ref/source/v1/parameters.yaml
@@ -646,6 +646,12 @@ engine_status:
   in: body
   required: true
   type: string
+Environment:
+  description: |
+    Environment for the stack, where multiple environment files are provided this will be the merged result.
+  in: body
+  required: false
+  type: object
 environment:
   description: |
     A JSON environment for the stack.
@@ -943,7 +949,7 @@ ParameterGroups:
   type: array
 Parameters:
   description: |
-    Key and value pairs that contain CFN template parameters.
+    Parameter schema in CFN format.
   in: body
   required: true
   type: object
diff --git a/api-ref/source/v1/samples/template-validate-response.json b/api-ref/source/v1/samples/template-validate-response.json
index cbdf7c26f..80c9374ab 100644
--- a/api-ref/source/v1/samples/template-validate-response.json
+++ b/api-ref/source/v1/samples/template-validate-response.json
@@ -37,5 +37,13 @@
                 "param_name-2"
             ]
         }
-    ]
+    ],
+    "Environment": {
+        "event_sinks": [],
+        "parameter_defaults": {},
+        "parameters": {},
+        "resource_registry": {
+            "resources": {}
+        }
+    }
 }
diff --git a/api-ref/source/v1/stack-templates.inc b/api-ref/source/v1/stack-templates.inc
index e9b735871..f6e0b42e9 100644
--- a/api-ref/source/v1/stack-templates.inc
+++ b/api-ref/source/v1/stack-templates.inc
@@ -145,6 +145,7 @@ Response Parameters
    - Description: Description
    - ParameterGroups: ParameterGroups
    - Parameters: Parameters
+   - Environment: Environment
 
 Response Example
 ----------------
diff --git a/heat/engine/service.py b/heat/engine/service.py
index 5c6e2eb41..fb94cb6b6 100644
--- a/heat/engine/service.py
+++ b/heat/engine/service.py
@@ -1310,6 +1310,7 @@ class EngineService(service.ServiceBase):
 
             result.update(nested_params(stack))
 
+        result['Environment'] = tmpl.env.user_env_as_dict()
         return result
 
     @context.request_context
diff --git a/heat/tests/test_validate.py b/heat/tests/test_validate.py
index 128e093f3..49e8e000d 100644
--- a/heat/tests/test_validate.py
+++ b/heat/tests/test_validate.py
@@ -880,6 +880,10 @@ parameters:
     type: string
     description: Name of private network to be created
 
+  merged_param:
+    type: comma_delimited_list
+    description: A merged list of values
+
 resources:
   private_net:
     type: OS::Neutron::Net
@@ -939,6 +943,11 @@ class ValidateTest(common.HeatTestCase):
         self.mock_is_service_available = self.mock_isa.start()
         self.addCleanup(self.mock_isa.stop)
         self.engine = service.EngineService('a', 't')
+        self.empty_environment = {
+            'event_sinks': [],
+            'parameter_defaults': {},
+            'parameters': {},
+            'resource_registry': {'resources': {}}}
 
     def _mock_get_image_id_success(self, imageId):
         self.patchobject(glance.GlanceClientPlugin, 'find_image_by_name_or_id',
@@ -1043,7 +1052,8 @@ class ValidateTest(common.HeatTestCase):
         other_template = test_template_no_default.replace(
             'net_name', 'net_name2')
 
-        files = {'env1': 'parameter_defaults:\n  net_name: net1',
+        files = {'env1': 'parameter_defaults:'
+                         '\n  net_name: net1',
                  'env2': 'parameter_defaults:'
                          '\n  net_name: net2'
                          '\n  net_name2: net3',
@@ -1051,12 +1061,72 @@ class ValidateTest(common.HeatTestCase):
                  'tmpl2.yaml': other_template}
         params = {'parameters': {}, 'parameter_defaults': {}}
 
-        self.engine.validate_template(
+        ret = self.engine.validate_template(
             self.ctx, t,
             params=params,
             files=files, environment_files=['env1', 'env2'])
         self.assertEqual('net2', params['parameter_defaults']['net_name'])
         self.assertEqual('net3', params['parameter_defaults']['net_name2'])
+        expected = {
+            'Description': 'No description',
+            'Parameters': {
+                'size': {'AllowedValues': [1, 4, 8],
+                         'Description': '',
+                         'Label': u'size',
+                         'NoEcho': 'false',
+                         'Type': 'Number'}},
+            'Environment': {
+                'event_sinks': [],
+                'parameter_defaults': {
+                    'net_name': u'net2',
+                    'net_name2': u'net3'},
+                'parameters': {},
+                'resource_registry': {'resources': {}}}}
+
+        self.assertEqual(expected, ret)
+
+    def test_validate_parameters_merged_env(self):
+        t = template_format.parse(test_template_allowed_integers)
+
+        other_template = test_template_no_default.replace(
+            'net_name', 'net_name2')
+
+        files = {'env1': 'parameter_defaults:'
+                         '\n  net_name: net1'
+                         '\n  merged_param: [net1, net2]'
+                         '\nparameter_merge_strategies:'
+                         '\n  merged_param: merge',
+                 'env2': 'parameter_defaults:'
+                         '\n  net_name: net2'
+                         '\n  net_name2: net3'
+                         '\n  merged_param: [net3, net4]'
+                         '\nparameter_merge_strategies:'
+                         '\n  merged_param: merge',
+                 'tmpl1.yaml': test_template_no_default,
+                 'tmpl2.yaml': other_template}
+        params = {'parameters': {}, 'parameter_defaults': {}}
+
+        expected = {
+            'Description': 'No description',
+            'Parameters': {
+                'size': {'AllowedValues': [1, 4, 8],
+                         'Description': '',
+                         'Label': u'size',
+                         'NoEcho': 'false',
+                         'Type': 'Number'}},
+            'Environment': {
+                'event_sinks': [],
+                'parameter_defaults': {
+                    'net_name': u'net2',
+                    'net_name2': u'net3',
+                    'merged_param': ['net1', 'net2', 'net3', 'net4']},
+                'parameters': {},
+                'resource_registry': {'resources': {}}}}
+        ret = self.engine.validate_template(
+            self.ctx, t,
+            params=params,
+            files=files, environment_files=['env1', 'env2'])
+        self.assertEqual(expected, ret)
 
     def test_validate_hot_empty_parameters_valid(self):
         t = template_format.parse(
@@ -1149,7 +1219,8 @@ class ValidateTest(common.HeatTestCase):
 
         res = dict(self.engine.validate_template(self.ctx, t, {}))
         expected = {"Description": "test.",
-                    "Parameters": {}}
+                    "Parameters": {},
+                    "Environment": self.empty_environment}
         self.assertEqual(expected, res)
 
     def test_validate_hot_empty_outputs_valid(self):
@@ -1162,7 +1233,8 @@ class ValidateTest(common.HeatTestCase):
 
         res = dict(self.engine.validate_template(self.ctx, t, {}))
         expected = {"Description": "test.",
-                    "Parameters": {}}
+                    "Parameters": {},
+                    "Environment": self.empty_environment}
         self.assertEqual(expected, res)
 
     def test_validate_properties(self):
@@ -1239,7 +1311,9 @@ class ValidateTest(common.HeatTestCase):
         t = template_format.parse(test_template_volume_snapshot)
 
         res = dict(self.engine.validate_template(self.ctx, t, {}))
-        self.assertEqual({'Description': u'test.', 'Parameters': {}}, res)
+        expected = {'Description': u'test.', 'Parameters': {},
+                    'Environment': self.empty_environment}
+        self.assertEqual(expected, res)
 
     def test_validate_template_without_resources(self):
         hot_tpl = template_format.parse('''
@@ -1247,7 +1321,8 @@ class ValidateTest(common.HeatTestCase):
         ''')
 
         res = dict(self.engine.validate_template(self.ctx, hot_tpl, {}))
-        expected = {'Description': 'No description', 'Parameters': {}}
+        expected = {'Description': 'No description', 'Parameters': {},
+                    'Environment': self.empty_environment}
         self.assertEqual(expected, res)
 
     def test_validate_template_with_invalid_resource_type(self):
@@ -1755,7 +1830,8 @@ class ValidateTest(common.HeatTestCase):
             t,
             {},
             ignorable_errors=[exception.ResourceTypeUnavailable.error_code]))
-        expected = {'Description': 'No description', 'Parameters': {}}
+        expected = {'Description': 'No description', 'Parameters': {},
+                    'Environment': self.empty_environment}
         self.assertEqual(expected, res)
 
     def test_validate_with_ignorable_errors_invalid_error_code(self):
@@ -1835,7 +1911,14 @@ parameter_groups:
                             'NoEcho': 'false',
                             'Type': 'String'}},
                     'Type': 'OS::Test::TestResource'}},
-        }
+            'Environment': {
+                'event_sinks': [],
+                'parameter_defaults': {},
+                'parameters': {},
+                'resource_registry': {
+                    'OS::Test::TestResource':
+                    'https://server.test/nested.template',
+                    'resources': {}}}}
         self.assertEqual(expected, res)
 
     def test_validate_allowed_external_rsrc(self):
diff --git a/heat_integrationtests/functional/test_template_validate.py b/heat_integrationtests/functional/test_template_validate.py
index e62c31b76..451de49c5 100644
--- a/heat_integrationtests/functional/test_template_validate.py
+++ b/heat_integrationtests/functional/test_template_validate.py
@@ -94,7 +94,12 @@ resources:
                                    'Description': 'the param description',
                                    'Label': 'aparam',
                                    'NoEcho': 'false',
-                                   'Type': 'Number'}}}
+                                   'Type': 'Number'}},
+                    'Environment': {
+                        'event_sinks': [],
+                        'parameter_defaults': {},
+                        'parameters': {},
+                        'resource_registry': {u'resources': {}}}}
         self.assertEqual(expected, ret)
 
     def test_template_validate_override_default(self):
@@ -108,7 +113,12 @@ resources:
                                    'Description': 'the param description',
                                    'Label': 'aparam',
                                    'NoEcho': 'false',
-                                   'Type': 'Number'}}}
+                                   'Type': 'Number'}},
+                    'Environment': {
+                        'event_sinks': [],
+                        'parameter_defaults': {},
+                        'parameters': {'aparam': 5},
+                        'resource_registry': {u'resources': {}}}}
         self.assertEqual(expected, ret)
 
     def test_template_validate_override_none(self):
@@ -122,7 +132,14 @@ resources:
                                    'Description': 'the param description',
                                    'Label': 'aparam',
                                    'NoEcho': 'false',
-                                   'Type': 'Number'}}}
+                                   'Type': 'Number'}},
+                    'Environment': {
+                        'event_sinks': [],
+                        'parameter_defaults': {},
+                        'parameters': {},
+                        'resource_registry': {
+                            'OS::Heat::RandomString': 'OS::Heat::None',
+                            u'resources': {}}}}
         self.assertEqual(expected, ret)
 
     def test_template_validate_basic_required_param(self):
@@ -133,7 +150,12 @@ resources:
                         'aparam': {'Description': 'the param description',
                                    'Label': 'aparam',
                                    'NoEcho': 'false',
-                                   'Type': 'Number'}}}
+                                   'Type': 'Number'}},
+                    'Environment': {
+                        'event_sinks': [],
+                        'parameter_defaults': {},
+                        'parameters': {},
+                        'resource_registry': {u'resources': {}}}}
         self.assertEqual(expected, ret)
 
     def test_template_validate_fail_version(self):
@@ -168,7 +190,12 @@ resources:
                       'Description': '',
                       'Label': 'cparam',
                       'NoEcho': 'true',
-                      'Type': 'String'}}}
+                      'Type': 'String'}},
+                    'Environment': {
+                        'event_sinks': [],
+                        'parameter_defaults': {},
+                        'parameters': {},
+                        'resource_registry': {u'resources': {}}}}
         self.assertEqual(expected, ret)
 
     def test_template_validate_nested_off(self):
@@ -181,7 +208,14 @@ resources:
                                    'Description': 'the param description',
                                    'Label': 'pparam',
                                    'NoEcho': 'false',
-                                   'Type': 'Number'}}}
+                                   'Type': 'Number'}},
+                    'Environment': {
+                        'event_sinks': [],
+                        'parameter_defaults': {},
+                        'parameters': {},
+                        'resource_registry': {
+                            u'mynested.yaml': u'mynested.yaml',
+                            u'resources': {}}}}
         self.assertEqual(expected, ret)
 
     def test_template_validate_nested_on(self):
@@ -200,7 +234,14 @@ resources:
                                                            'Label': 'aparam',
                                                            'NoEcho': 'false',
                                                            'Type': 'Number'}},
-                                 'Type': 'mynested.yaml'}}}
+                                 'Type': 'mynested.yaml'}},
+                    'Environment': {
+                        'event_sinks': [],
+                        'parameter_defaults': {},
+                        'parameters': {},
+                        'resource_registry': {
+                            u'mynested.yaml': u'mynested.yaml',
+                            u'resources': {}}}}
         self.assertEqual(expected, ret)
 
     def test_template_validate_nested_on_multiple(self):
@@ -240,5 +281,12 @@ resources:
                                                            'NoEcho': 'false',
                                                            'Type': 'Number'}},
                                  'NestedParameters': n_param2,
-                                 'Type': 'mynested.yaml'}}}
+                                 'Type': 'mynested.yaml'}},
+                    'Environment': {
+                        'event_sinks': [],
+                        'parameter_defaults': {},
+                        'parameters': {},
+                        'resource_registry': {
+                            u'mynested.yaml': u'mynested.yaml',
+                            'resources': {}}}}
         self.assertEqual(expected, ret)
diff --git a/heat_integrationtests/functional/test_unicode_template.py b/heat_integrationtests/functional/test_unicode_template.py
index 32c02a5cd..d5776a409 100644
--- a/heat_integrationtests/functional/test_unicode_template.py
+++ b/heat_integrationtests/functional/test_unicode_template.py
@@ -72,6 +72,12 @@ outputs:
                     'Label': u'\u6807\u7b7e',
                     'NoEcho': 'false',
                     'Type': 'Number'}
+            },
+            'Environment': {
+                'event_sinks': [],
+                'parameter_defaults': {},
+                'parameters': {},
+                'resource_registry': {u'resources': {}}
             }
         }
         self.assertEqual(expected, ret)
@@ -90,6 +96,12 @@ outputs:
                     'Label': u'\u6807\u7b7e',
                     'NoEcho': 'false',
                     'Type': 'Number'}
+            },
+            'Environment': {
+                'event_sinks': [],
+                'parameter_defaults': {},
+                'parameters': {u'\u53c2\u6570': 5},
+                'resource_registry': {u'resources': {}}
             }
         }
         self.assertEqual(expected, ret)
diff --git a/releasenotes/notes/environment_validate_template-fee21a03bb628446.yaml b/releasenotes/notes/environment_validate_template-fee21a03bb628446.yaml
new file mode 100644
index 000000000..e5b07970f
--- /dev/null
+++ b/releasenotes/notes/environment_validate_template-fee21a03bb628446.yaml
@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    The template validate API call now returns the Environment calculated by
+    heat - this enables preview of the merged environment when using
+    parameter_merge_strategy prior to creating the stack