Repro allocation show bug with empty allocation

This patch adds a functional test case to reproduce the bug when an
allocation show command on an empty (non existent) allocation causes
KeyError as the code expects project_id in the response but the
response is {"allocations":{}}. Also similarly for allocation unset
where microversion 1.38 fails on parsing out consumer_type from the
empty allocation too.

Related-Bug: #1942740

Change-Id: Iea27c9376480e3e94d12eec56b466331e5c6f171

osc_placement/tests/functional/base.py

@@ -228,11 +228,10 @@ class BaseTestCase(base.BaseTestCase):
     def resource_provider_delete(self, uuid):
         return self.openstack('resource provider delete ' + uuid)
 
-    def resource_allocation_show(self, consumer_uuid):
-        return self.openstack(
-            'resource provider allocation show ' + consumer_uuid,
-            use_json=True
-        )
+    def resource_allocation_show(self, consumer_uuid, columns=()):
+        cmd = 'resource provider allocation show ' + consumer_uuid
+        cmd += ' '.join(' --column %s' % c for c in columns)
+        return self.openstack(cmd, use_json=True)
 
     def resource_allocation_set(self, consumer_uuid, allocations,
                                 project_id=None, user_id=None,
@@ -262,8 +261,10 @@ class BaseTestCase(base.BaseTestCase):
 
         return result
 
-    def resource_allocation_unset(self, consumer_uuid, provider=None,
-                                  resource_class=None, use_json=True):
+    def resource_allocation_unset(
+        self, consumer_uuid, provider=None, resource_class=None, use_json=True,
+        columns=(),
+    ):
         cmd = 'resource provider allocation unset %s' % consumer_uuid
         if resource_class:
             cmd += ' ' + ' '.join(
@@ -275,6 +276,9 @@ class BaseTestCase(base.BaseTestCase):
                 provider = [provider]
             cmd += ' ' + ' '.join(
                 '--provider %s' % rp_uuid for rp_uuid in provider)
+
+        cmd += ' '.join(' --column %s' % c for c in columns)
+
         result = self.openstack(cmd, use_json=use_json)
 
         def cleanup(uuid):

osc_placement/tests/functional/test_allocation.py

@@ -180,6 +180,38 @@ class TestAllocation112(base.BaseTestCase):
         self.assertEqual(expected, created_alloc)
         self.assertEqual(expected, retrieved_alloc)
 
+    def test_allocation_update_to_empty(self):
+        consumer_uuid = str(uuid.uuid4())
+        project_uuid = str(uuid.uuid4())
+        user_uuid = str(uuid.uuid4())
+
+        self.resource_allocation_set(
+            consumer_uuid,
+            ['rp={},VCPU=2'.format(self.rp1['uuid'])],
+            project_id=project_uuid,
+            user_id=user_uuid,
+        )
+
+        result = self.resource_allocation_unset(
+            consumer_uuid, columns=("resources",))
+
+        self.assertEqual([], result)
+
+    def test_allocation_show_empty(self):
+        # FIXME(gibi): this is bug https://bugs.launchpad.net/nova/+bug/1942740
+        # the command fails with KeyError on project_id when the allocation is
+        # empty
+        self.assertCommandFailed(
+            'project_id',
+            self.resource_allocation_show,
+            str(uuid.uuid4()),
+            columns=("resources",),
+        )
+        # it should be
+        # alloc = self.resource_allocation_show(
+        #     str(uuid.uuid4()), columns=("resources",))
+        # self.assertEqual([], alloc)
+
 
 class TestAllocation128(TestAllocation112):
     """Tests allocation set command with --os-placement-api-version 1.28.
@@ -272,6 +304,33 @@ class TestAllocation138(TestAllocation128):
         })
         self.assertEqual(expected, updated_alloc)
 
+    def test_allocation_update_to_empty(self):
+        consumer_uuid = str(uuid.uuid4())
+        project_uuid = str(uuid.uuid4())
+        user_uuid = str(uuid.uuid4())
+
+        self.resource_allocation_set(
+            consumer_uuid,
+            ['rp={},VCPU=2'.format(self.rp1['uuid'])],
+            project_id=project_uuid,
+            user_id=user_uuid,
+            consumer_type="INSTANCE",
+        )
+
+        # FIXME(gibi): This is bug https://bugs.launchpad.net/nova/+bug/1942740
+        # The command fails with a KeyError as it tries to parse the
+        # consumer_type out from and empty allocation
+        self.assertCommandFailed(
+            "consumer_type",
+            self.resource_allocation_unset,
+            consumer_uuid,
+            columns=('resources', 'consumer_type')
+        )
+        # it should be
+        # result = self.resource_allocation_unset(
+        #     consumer_uuid, columns=('resources', 'consumer_type'))
+        # self.assertEqual([], result)
+
 
 class TestAllocationUnsetOldVersion(base.BaseTestCase):