From 58f8f93b52e7de2d3751dd3291427a65a3c1079b Mon Sep 17 00:00:00 2001
From: Mark Washenberger <mark.washenberger@rackspace.com>
Date: Fri, 10 Feb 2012 13:46:24 -0500
Subject: Handle network api failures more gracefully

addresses bug 930329

Change-Id: Idb0934b9dd6ebc0e5e81495fb4454e4e50bc1f57
---
 nova/api/openstack/common.py            | 11 +++++++++--
 nova/tests/api/openstack/test_common.py | 11 +++++++++++
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/nova/api/openstack/common.py b/nova/api/openstack/common.py
index c19b8f103..a7ec48f70 100644
--- a/nova/api/openstack/common.py
+++ b/nova/api/openstack/common.py
@@ -27,6 +27,7 @@ from nova.api.openstack import wsgi
 from nova.api.openstack import xmlutil
 from nova.compute import vm_states
 from nova.compute import task_states
+from nova import exception
 from nova import flags
 from nova import log as logging
 from nova import network
@@ -333,10 +334,16 @@ def get_networks_for_instance(context, instance):
         #                sqlalchemy FK (KeyError, AttributeError)
         #                fail fall back to calling out the the
         #                network api
-        network_api = network.API()
+        pass
 
+    network_api = network.API()
+
+    try:
         nw_info = network_api.get_instance_nw_info(context, instance)
-        return get_networks_for_instance_from_nw_info(nw_info)
+    except exception.InstanceNotFound:
+        nw_info = []
+
+    return get_networks_for_instance_from_nw_info(nw_info)
 
 
 def raise_http_conflict_for_instance_invalid_state(exc, action):
diff --git a/nova/tests/api/openstack/test_common.py b/nova/tests/api/openstack/test_common.py
index e8f967976..6103b6d13 100644
--- a/nova/tests/api/openstack/test_common.py
+++ b/nova/tests/api/openstack/test_common.py
@@ -26,6 +26,7 @@ from webob import Request
 import xml.dom.minidom as minidom
 
 from nova import exception
+from nova import network
 from nova import test
 from nova.api.openstack import common
 from nova.api.openstack import xmlutil
@@ -328,6 +329,16 @@ class MiscFunctionsTest(test.TestCase):
         else:
             self.fail("webob.exc.HTTPConflict was not raised")
 
+    def test_get_networks_for_instance_handles_instance_not_found(self):
+
+        def raise_not_found(*args, **kwargs):
+            raise exception.InstanceNotFound(instance_id='abcd')
+
+        self.stubs.Set(network.API, 'get_instance_nw_info', raise_not_found)
+
+        networks = common.get_networks_for_instance(context={}, instance={})
+        self.assertEqual(networks, {})
+
 
 class MetadataXMLDeserializationTest(test.TestCase):
 
-- 
cgit