From c2d9a6fdfddc1bcc6c687946f320669cf0a73173 Mon Sep 17 00:00:00 2001
From: Shane Wang <shane.wang@intel.com>
Date: Mon, 6 Jan 2014 13:51:36 +0800
Subject: [PATCH] Prevent caller from specifying id during ComputeNode.create()

The patch is to remove id when it was set before creating a compute
node in objects, so it can be generated automatically.

And check if the node exists before it is created.

Related to blueprint icehouse-objects.

Change-Id: Ib808643bff24b683ef330b5a1be5bc68ece30184
---
 nova/objects/compute_node.py            |  5 +++++
 nova/tests/objects/test_compute_node.py | 12 ++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/nova/objects/compute_node.py b/nova/objects/compute_node.py
index b277be97f023..9db1c6cce536 100644
--- a/nova/objects/compute_node.py
+++ b/nova/objects/compute_node.py
@@ -13,6 +13,7 @@
 #    under the License.
 
 from nova import db
+from nova import exception
 from nova.objects import base
 from nova.objects import fields
 
@@ -64,7 +65,11 @@ class ComputeNode(base.NovaPersistentObject, base.NovaObject):
 
     @base.remotable
     def create(self, context):
+        if self.obj_attr_is_set('id'):
+            raise exception.ObjectActionError(action='create',
+                                              reason='already created')
         updates = self.obj_get_changes()
+        updates.pop('id', None)
         db_compute = db.compute_node_create(context, updates)
         self._from_db_object(context, self, db_compute)
 
diff --git a/nova/tests/objects/test_compute_node.py b/nova/tests/objects/test_compute_node.py
index f1ad6cac9f6c..c0ae9763bd88 100644
--- a/nova/tests/objects/test_compute_node.py
+++ b/nova/tests/objects/test_compute_node.py
@@ -13,6 +13,7 @@
 #    under the License.
 
 from nova import db
+from nova import exception
 from nova.objects import compute_node
 from nova.objects import service
 from nova.openstack.common import timeutils
@@ -71,6 +72,17 @@ class _TestComputeNodeObject(object):
         compute.create(self.context)
         self.compare_obj(compute, fake_compute_node)
 
+    def test_recreate_fails(self):
+        self.mox.StubOutWithMock(db, 'compute_node_create')
+        db.compute_node_create(self.context, {'service_id': 456}).AndReturn(
+            fake_compute_node)
+        self.mox.ReplayAll()
+        compute = compute_node.ComputeNode()
+        compute.service_id = 456
+        compute.create(self.context)
+        self.assertRaises(exception.ObjectActionError, compute.create,
+                          self.context)
+
     def test_save(self):
         self.mox.StubOutWithMock(db, 'compute_node_update')
         db.compute_node_update(self.context, 123, {'vcpus_used': 3},