From d7a5169a7f0ffe7208f851b554b7b1ed5145a3be Mon Sep 17 00:00:00 2001
From: Brian Waldon <brian.waldon@rackspace.com>
Date: Thu, 3 Nov 2011 13:40:56 -0400
Subject: [PATCH] Gracefully handle Xen resize failure

Fixes bug 885723

Change-Id: I8cd04a88f809f49141dc6aa5be7217811e0141e3
---
 nova/tests/test_compute.py | 24 ++++++++++++++++++++++++
 nova/tests/test_xenapi.py  | 13 +++++++++++++
 2 files changed, 37 insertions(+)

diff --git a/nova/tests/test_compute.py b/nova/tests/test_compute.py
index 7295c9f1..b235bcad 100644
--- a/nova/tests/test_compute.py
+++ b/nova/tests/test_compute.py
@@ -746,6 +746,30 @@ class ComputeTestCase(test.TestCase):
                 self.context, inst_ref['uuid'], 1)
         self.compute.terminate_instance(self.context, instance_id)
 
+    def test_resize_instance_handles_migration_error(self):
+        """Ensure vm_state is ERROR when MigrationError occurs"""
+        def raise_migration_failure(*args):
+            raise exception.MigrationError(reason='test failure')
+        self.stubs.Set(self.compute.driver,
+                'migrate_disk_and_power_off',
+                raise_migration_failure)
+
+        instance_id = self._create_instance()
+        context = self.context.elevated()
+        inst_ref = db.instance_get(context, instance_id)
+
+        self.compute.run_instance(self.context, instance_id)
+        db.instance_update(self.context, inst_ref['uuid'], {'host': 'foo'})
+        self.compute.prep_resize(context, inst_ref['uuid'], 1)
+        migration_ref = db.migration_get_by_instance_and_status(context,
+                inst_ref['uuid'], 'pre-migrating')
+        self.compute.resize_instance(context,
+                                     inst_ref['uuid'],
+                                     migration_ref['id'])
+        inst_ref = db.instance_get(context, instance_id)
+        self.assertEqual(inst_ref['vm_state'], vm_states.ERROR)
+        self.compute.terminate_instance(context, instance_id)
+
     def test_migrate(self):
         context = self.context.elevated()
         instance_id = self._create_instance()
diff --git a/nova/tests/test_xenapi.py b/nova/tests/test_xenapi.py
index 08a7686b..6587bedd 100644
--- a/nova/tests/test_xenapi.py
+++ b/nova/tests/test_xenapi.py
@@ -791,6 +791,19 @@ class XenAPIMigrateInstance(test.TestCase):
         conn = xenapi_conn.get_connection(False)
         conn.migrate_disk_and_power_off(self.context, instance, '127.0.0.1')
 
+    def test_migrate_disk_and_power_off_passes_exceptions(self):
+        instance = db.instance_create(self.context, self.instance_values)
+        stubs.stubout_session(self.stubs, stubs.FakeSessionForMigrationTests)
+
+        def fake_raise(*args, **kwargs):
+            raise exception.MigrationError(reason='test failure')
+        self.stubs.Set(vmops.VMOps, "_migrate_vhd", fake_raise)
+
+        conn = xenapi_conn.get_connection(False)
+        self.assertRaises(exception.MigrationError,
+                          conn.migrate_disk_and_power_off,
+                          self.context, instance, '127.0.0.1')
+
     def test_revert_migrate(self):
         instance = db.instance_create(self.context, self.instance_values)
         self.called = False