Ensure deleted instances' status is always DELETED

Currently when deleting failed instances that were never assigned a
host, their vm_state is left in 'error' instead of 'deleted'. This is a
problem when invoking the Index Instances REST API with a Changes-Since
query parameter since that API returns both deleted and non-deleted
instances, but currently the failed deleted instances are incorrectly
marked as status:ERROR instead of status:DELETED.

This patch modifies the server ViewBuilder to ensure the status is
correctly set.

Change-Id: I614714676bab4986564b236d74f2c0d77400e48c
Closes-bug: #1243301
(cherry picked from commit 38018d3)

nova/api/openstack/compute/views/servers.py

@@ -47,7 +47,7 @@ class ViewBuilder(common.ViewBuilder):
     )
 
     _fault_statuses = (
-        "ERROR",
+        "ERROR", "DELETED"
     )
 
     def __init__(self):
@@ -147,6 +147,9 @@ def _get_metadata(instance):
 
     @staticmethod
     def _get_vm_state(instance):
+        # If the instance is deleted the vm and task states don't really matter
+        if instance.get("deleted"):
+            return "DELETED"
         return common.status_from_state(instance.get("vm_state"),
                                         instance.get("task_state"))
 

nova/tests/api/openstack/compute/plugins/v3/test_servers.py

@@ -2999,6 +2999,24 @@ def test_build_server_detail_with_fault(self):
         output = self.view_builder.show(self.request, self.instance)
         self.assertThat(output, matchers.DictMatches(expected_server))
 
+    def test_build_server_detail_with_fault_that_has_been_deleted(self):
+        self.instance['deleted'] = 1
+        self.instance['vm_state'] = vm_states.ERROR
+        fault = fake_instance.fake_fault_obj(self.uuid, code=500,
+                                             message="No valid host was found")
+        self.instance['fault'] = fault
+
+        expected_fault = {"code": 500,
+                          "created": "2010-10-10T12:00:00Z",
+                          "message": "No valid host was found"}
+
+        self.request.context = context.RequestContext('fake', 'fake')
+        output = self.view_builder.show(self.request, self.instance)
+        # Regardless of vm_state deleted servers sholud be DELETED
+        self.assertEqual("DELETED", output['server']['status'])
+        self.assertThat(output['server']['fault'],
+                        matchers.DictMatches(expected_fault))
+
     def test_build_server_detail_with_fault_no_details_not_admin(self):
         self.instance['vm_state'] = vm_states.ERROR
         self.instance['fault'] = fake_instance.fake_fault_obj(

nova/tests/api/openstack/compute/test_servers.py

@@ -3863,6 +3863,27 @@ def test_build_server_detail_with_fault(self):
         self.assertThat(output,
                 matchers.DictMatches(self.expected_detailed_server))
 
+    def test_build_server_detail_with_fault_that_has_been_deleted(self):
+        self.instance['deleted'] = 1
+        self.instance['vm_state'] = vm_states.ERROR
+        fault = fake_instance.fake_fault_obj(self.uuid, code=500,
+                                             message="No valid host was found")
+        self.instance['fault'] = fault
+
+        # Regardless of the vm_state deleted servers sholud have DELETED status
+        self.expected_detailed_server["server"]["status"] = "DELETED"
+        self.expected_detailed_server["server"]["fault"] = {
+                    "code": 500,
+                    "created": "2010-10-10T12:00:00Z",
+                    "message": "No valid host was found",
+                }
+        del self.expected_detailed_server["server"]["progress"]
+
+        self.request.context = context.RequestContext('fake', 'fake')
+        output = self.view_builder.show(self.request, self.instance)
+        self.assertThat(output,
+                matchers.DictMatches(self.expected_detailed_server))
+
     def test_build_server_detail_with_fault_no_details_not_admin(self):
         self.instance['vm_state'] = vm_states.ERROR
         self.instance['fault'] = fake_instance.fake_fault_obj(