Move merge_environment to environment_util module

This moves the merge_environment utility function
from service.py to environment_util.py.

Change-Id: Ia005cf47d5e655e60359f8da397a712e749ce13c
Blueprint: environment-merging

7 files changed, 100 insertions, 81 deletions

diff --git a/heat/common/environment_util.py b/heat/common/environment_util.py
index 5ee4f4984..b19a4606d 100644
--- a/heat/common/environment_util.py
+++ b/heat/common/environment_util.py
@@ -10,6 +10,9 @@
 #    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 #    License for the specific language governing permissions and limitations
 #    under the License.
+import collections
+
+from heat.common import environment_format
 
 ALLOWED_PARAM_MERGE_STRATEGIES = (OVERWRITE, MERGE, DEEP_MERGE) = (
     'overwrite', 'merge', 'deep_merge')
@@ -27,3 +30,38 @@ def get_param_merge_strategy(merge_strategies, param_key):
         return merge_strategy
 
     return env_default
+
+
+def deep_update(old, new):
+    '''Merge nested dictionaries.'''
+    for k, v in new.items():
+        if isinstance(v, collections.Mapping):
+            r = deep_update(old.get(k, {}), v)
+            old[k] = r
+        else:
+            old[k] = new[k]
+    return old
+
+
+def merge_environments(environment_files, files, params):
+    """Merges environment files into the stack input parameters.
+
+    If a list of environment files have been specified, this call will
+    pull the contents of each from the files dict, parse them as
+    environments, and merge them into the stack input params. This
+    behavior is the same as earlier versions of the Heat client that
+    performed this params population client-side.
+
+    :param environment_files: ordered names of the environment files
+           found in the files dict
+    :type  environment_files: list or None
+    :param files: mapping of stack filenames to contents
+    :type  files: dict
+    :param params: parameters describing the stack
+    :type  dict:
+    """
+    if environment_files:
+        for filename in environment_files:
+            raw_env = files[filename]
+            parsed_env = environment_format.parse(raw_env)
+            deep_update(params, parsed_env)
diff --git a/heat/engine/service.py b/heat/engine/service.py
index 49788d4da..ebe1193d9 100644
--- a/heat/engine/service.py
+++ b/heat/engine/service.py
@@ -33,6 +33,7 @@ import webob
 
 from heat.common import context
 from heat.common import environment_format as env_fmt
+from heat.common import environment_util as env_util
 from heat.common import exception
 from heat.common.i18n import _
 from heat.common.i18n import _LE
@@ -69,8 +70,6 @@ from heat.objects import watch_data
 from heat.objects import watch_rule
 from heat.rpc import api as rpc_api
 from heat.rpc import worker_api as rpc_worker_api
-from heatclient.common import environment_format
-from heatclient.common import template_utils
 
 cfg.CONF.import_opt('engine_life_check_timeout', 'heat.common.config')
 cfg.CONF.import_opt('max_resources_per_stack', 'heat.common.config')
@@ -680,7 +679,7 @@ class EngineService(service.Service):
             tmpl = templatem.Template.load(cnxt, template_id)
             env = tmpl.env
         else:
-            self._merge_environments(environment_files, files, params)
+            env_util.merge_environments(environment_files, files, params)
             env = environment.Environment(params)
             tmpl = templatem.Template(template, files=files, env=env)
         self._validate_new_stack(cnxt, stack_name, tmpl)
@@ -701,30 +700,6 @@ class EngineService(service.Service):
             env.registry.log_resource_info(prefix=stack_name)
         return stack
 
-    @staticmethod
-    def _merge_environments(environment_files, files, params):
-        """Merges environment files into the stack input parameters.
-
-        If a list of environment files have been specified, this call will
-        pull the contents of each from the files dict, parse them as
-        environments, and merge them into the stack input params. This
-        behavior is the same as earlier versions of the Heat client that
-        performed this params population client-side.
-
-        :param environment_files: ordered names of the environment files
-               found in the files dict
-        :type  environment_files: list or None
-        :param files: mapping of stack filenames to contents
-        :type  files: dict
-        :param params: parameters describing the stack
-        :type  dict:
-        """
-        if environment_files:
-            for filename in environment_files:
-                raw_env = files[filename]
-                parsed_env = environment_format.parse(raw_env)
-                template_utils.deep_update(params, parsed_env)
-
     @context.request_context
     def preview_stack(self, cnxt, stack_name, template, params, files,
                       args, environment_files=None):
@@ -969,7 +944,7 @@ class EngineService(service.Service):
         :param template_id: the ID of a pre-stored template in the DB
         """
         # Handle server-side environment file resolution
-        self._merge_environments(environment_files, files, params)
+        env_util.merge_environments(environment_files, files, params)
 
         # Get the database representation of the existing stack
         db_stack = self._get_stack(cnxt, stack_identity)
@@ -1026,7 +1001,7 @@ class EngineService(service.Service):
         heat-api process if using a template-url.
         """
         # Handle server-side environment file resolution
-        self._merge_environments(environment_files, files, params)
+        env_util.merge_environments(environment_files, files, params)
 
         # Get the database representation of the existing stack
         db_stack = self._get_stack(cnxt, stack_identity)
@@ -1206,7 +1181,7 @@ class EngineService(service.Service):
 
             service_check_defer = True
 
-        self._merge_environments(environment_files, files, params)
+        env_util.merge_environments(environment_files, files, params)
         env = environment.Environment(params)
         tmpl = templatem.Template(template, files=files, env=env)
         try:
diff --git a/heat/tests/engine/service/test_service_engine.py b/heat/tests/engine/service/test_service_engine.py
index 0aa2d41b3..8fb3226c1 100644
--- a/heat/tests/engine/service/test_service_engine.py
+++ b/heat/tests/engine/service/test_service_engine.py
@@ -411,50 +411,3 @@ class ServiceEngineTest(common.HeatTestCase):
         self.eng.start()
         self.assertEqual(cfg.CONF.executor_thread_pool_size,
                          cfg.CONF.database.max_overflow)
-
-    def test_merge_environments(self):
-        # Setup
-        params = {'parameters': {
-            'p0': 'CORRECT',
-            'p1': 'INCORRECT',
-            'p2': 'INCORRECT'}
-        }
-        env_1 = '''
-        {'parameters' : {
-            'p1': 'CORRECT',
-            'p2': 'INCORRECT-ENV-1',
-        }}'''
-        env_2 = '''
-        {'parameters': {
-            'p2': 'CORRECT'
-        }}'''
-
-        files = {'env_1': env_1, 'env_2': env_2}
-        environment_files = ['env_1', 'env_2']
-
-        # Test
-        self.eng._merge_environments(environment_files, files, params)
-
-        # Verify
-        expected = {'parameters': {
-            'p0': 'CORRECT',
-            'p1': 'CORRECT',
-            'p2': 'CORRECT',
-        }}
-        self.assertEqual(expected, params)
-
-    def test_merge_environments_no_env_files(self):
-        params = {'parameters': {'p0': 'CORRECT'}}
-        env_1 = '''
-        {'parameters' : {
-            'p0': 'INCORRECT',
-        }}'''
-
-        files = {'env_1': env_1}
-
-        # Test - Should ignore env_1 in files
-        self.eng._merge_environments(None, files, params)
-
-        # Verify
-        expected = {'parameters': {'p0': 'CORRECT'}}
-        self.assertEqual(expected, params)
diff --git a/heat/tests/engine/service/test_stack_create.py b/heat/tests/engine/service/test_stack_create.py
index 761b9aea4..0db72f67e 100644
--- a/heat/tests/engine/service/test_stack_create.py
+++ b/heat/tests/engine/service/test_stack_create.py
@@ -16,6 +16,7 @@ from oslo_messaging.rpc import dispatcher
 from oslo_service import threadgroup
 import six
 
+from heat.common import environment_util as env_util
 from heat.common import exception
 from heat.engine.clients.os import glance
 from heat.engine.clients.os import nova
@@ -54,7 +55,7 @@ class StackCreateTest(common.HeatTestCase):
         mock_env = self.patchobject(environment, 'Environment',
                                     return_value=stk.env)
         mock_stack = self.patchobject(stack, 'Stack', return_value=stk)
-        mock_merge = self.patchobject(self.man, '_merge_environments')
+        mock_merge = self.patchobject(env_util, 'merge_environments')
         result = self.man.create_stack(self.ctx, stack_name,
                                        template, params, None, {},
                                        environment_files=environment_files)
diff --git a/heat/tests/engine/service/test_stack_update.py b/heat/tests/engine/service/test_stack_update.py
index 4b1b70cae..49d736788 100644
--- a/heat/tests/engine/service/test_stack_update.py
+++ b/heat/tests/engine/service/test_stack_update.py
@@ -18,6 +18,7 @@ from oslo_config import cfg
 from oslo_messaging.rpc import dispatcher
 import six
 
+from heat.common import environment_util as env_util
 from heat.common import exception
 from heat.common import messaging
 from heat.common import service_utils
@@ -121,7 +122,7 @@ class ServiceStackUpdateTest(common.HeatTestCase):
         self.patchobject(eventlet.queue, 'LightQueue',
                          return_value=mock.Mock())
 
-        mock_merge = self.patchobject(self.man, '_merge_environments')
+        mock_merge = self.patchobject(env_util, 'merge_environments')
 
         # Test
         environment_files = ['env_1']
@@ -991,7 +992,7 @@ resources:
         mock_env = self.patchobject(environment, 'Environment',
                                     return_value=stk.env)
         mock_validate = self.patchobject(stk, 'validate', return_value=None)
-        mock_merge = self.patchobject(self.man, '_merge_environments')
+        mock_merge = self.patchobject(env_util, 'merge_environments')
 
         # Patch _resolve_all_attributes or it tries to call novaclient
         self.patchobject(resource.Resource, '_resolve_all_attributes',
diff --git a/heat/tests/test_common_env_util.py b/heat/tests/test_common_env_util.py
index bfcb8665e..b8975462d 100644
--- a/heat/tests/test_common_env_util.py
+++ b/heat/tests/test_common_env_util.py
@@ -48,3 +48,53 @@ class TestEnvironmentUtil(common.HeatTestCase):
         param_strategy = env_util.get_param_merge_strategy(merge_strategies,
                                                            'param1')
         self.assertEqual(env_util.OVERWRITE, param_strategy)
+
+
+class TestMergeEnvironments(common.HeatTestCase):
+
+    def test_merge_environments(self):
+        # Setup
+        params = {'parameters': {
+            'p0': 'CORRECT',
+            'p1': 'INCORRECT',
+            'p2': 'INCORRECT'}
+        }
+        env_1 = '''
+        {'parameters' : {
+            'p1': 'CORRECT',
+            'p2': 'INCORRECT-ENV-1',
+        }}'''
+        env_2 = '''
+        {'parameters': {
+            'p2': 'CORRECT'
+        }}'''
+
+        files = {'env_1': env_1, 'env_2': env_2}
+        environment_files = ['env_1', 'env_2']
+
+        # Test
+        env_util.merge_environments(environment_files, files, params)
+
+        # Verify
+        expected = {'parameters': {
+            'p0': 'CORRECT',
+            'p1': 'CORRECT',
+            'p2': 'CORRECT',
+        }}
+        self.assertEqual(expected, params)
+
+    def test_merge_environments_no_env_files(self):
+        params = {'parameters': {'p0': 'CORRECT'}}
+        env_1 = '''
+        {'parameters' : {
+            'p0': 'INCORRECT',
+        }}'''
+
+        files = {'env_1': env_1}
+
+        # Test - Should ignore env_1 in files
+        env_util.merge_environments(None, files, params)
+
+        # Verify
+        expected = {'parameters': {'p0': 'CORRECT'}}
+        self.assertEqual(expected, params)
diff --git a/heat/tests/test_engine_service.py b/heat/tests/test_engine_service.py
index 60a1bb0ab..d70dfa2f3 100644
--- a/heat/tests/test_engine_service.py
+++ b/heat/tests/test_engine_service.py
@@ -21,6 +21,7 @@ from oslo_serialization import jsonutils as json
 import six
 
 from heat.common import context
+from heat.common import environment_util as env_util
 from heat.common import exception
 from heat.common import identifier
 from heat.common import template_format
@@ -1165,7 +1166,7 @@ class StackServiceTest(common.HeatTestCase):
                                self._preview_stack)
         self.assertEqual(exception.StackValidationFailed, ex.exc_info[0])
 
-    @mock.patch.object(service.EngineService, '_merge_environments')
+    @mock.patch.object(env_util, 'merge_environments')
     def test_preview_environment_files(self, mock_merge):
         # Setup
         environment_files = ['env_1']