Make placement a required interface as of train

Make placement a required interface for train and above as
placement is required in order to schedule instances.

Change-Id: If2472ec24df4c3d90b14189f8c4d3cceee5edc97
Closes-Bug: #1849893

hooks/nova_cc_context.py

@@ -115,6 +115,18 @@ class CloudComputeContext(ch_context.OSContextGenerator):
         return ctxt
 
 
+class PlacementContext(ch_context.OSContextGenerator):
+    "Dummy context used by service status to check relation exists"
+    interfaces = ['placement']
+
+    def __call__(self):
+        ctxt = {}
+        rids = [rid for rid in hookenv.relation_ids('placement')]
+        if rids:
+            ctxt['rids'] = rids
+        return ctxt
+
+
 class NeutronAPIContext(ch_context.OSContextGenerator):
     interfaces = ['neutron-api']
 

hooks/nova_cc_utils.py

@@ -53,6 +53,10 @@ REQUIRED_INTERFACES = {
     'compute': ['nova-compute', 'nova-cell-api'],
 }
 
+REQUIRED_INTERFACES_TRAIN = {
+    'placement': ['placement'],
+}
+
 # removed from original: charm-helper-sh
 BASE_PACKAGES = [
     'apache2',
@@ -180,6 +184,7 @@ def get_base_resource_map():
                     nova_cc_context.InstanceConsoleContext(),
                     nova_cc_context.ConsoleSSLContext(),
                     nova_cc_context.CloudComputeContext(),
+                    nova_cc_context.PlacementContext(),
                     ch_context.InternalEndpointContext(),
                     ch_context.VolumeAPIContext('nova-common'),
                     nova_cc_context.NeutronAPIContext(),
@@ -1731,7 +1736,11 @@ def assess_status_func(configs):
     @param configs: a templating.OSConfigRenderer() object
     @return f() -> None : a function that assesses the unit's workload status
     """
+    release = ch_utils.os_release('nova-common')
+    cmp_os_release = ch_utils.CompareOpenStackReleases(release)
     required_interfaces = REQUIRED_INTERFACES.copy()
+    if cmp_os_release >= 'train':
+        required_interfaces.update(REQUIRED_INTERFACES_TRAIN)
     required_interfaces.update(get_optional_interfaces())
     return ch_utils.make_assess_status_func(
         configs, required_interfaces,

unit_tests/test_nova_cc_utils.py

@@ -1260,13 +1260,16 @@ class NovaCCUtilsTests(CharmTestCase):
     @patch.object(utils, 'services')
     @patch.object(utils, 'determine_ports')
     @patch.object(utils.ch_utils, 'make_assess_status_func')
+    @patch.object(utils.ch_utils, 'CompareOpenStackReleases')
     def test_assess_status_func(self,
+                                compare_releases,
                                 make_assess_status_func,
                                 determine_ports,
                                 services,
                                 REQUIRED_INTERFACES,
                                 check_optional_relations,
                                 get_optional_interfaces):
+        compare_releases.return_value = 'stein'
         services.return_value = 's1'
         REQUIRED_INTERFACES.copy.return_value = {'int': ['test 1']}
         get_optional_interfaces.return_value = {'opt': ['test 2']}
@@ -1279,6 +1282,15 @@ class NovaCCUtilsTests(CharmTestCase):
             charm_func=check_optional_relations, services='s1',
             ports=None)
 
+        make_assess_status_func.reset_mock()
+        compare_releases.return_value = 'train'
+        utils.assess_status_func('test-config')
+        make_assess_status_func.assert_called_once_with(
+            'test-config',
+            {'int': ['test 1'], 'placement': ['placement'], 'opt': ['test 2']},
+            charm_func=check_optional_relations, services='s1',
+            ports=None)
+
     def test_pause_unit_helper(self):
         with patch.object(utils, '_pause_resume_helper') as prh:
             utils.pause_unit_helper('random-config')