Update vmops to access metadata as dict.

Updates the inject_instance_metadata in xenapi/vmops.py so
that it accesses metadata as a dict instead of an object.

This resolves issues causing exceptions when booting instances
on XenServer.

Fixes LP Bug #1033963

Change-Id: I58810764abd32d9d292f8282b54c126bf1f4de18

nova/tests/test_xenapi.py

@@ -2261,22 +2261,19 @@ def fake_delete_from_xenstore(inst, instance, path, vm_ref=None):
                        fake_delete_from_xenstore)
 
     def test_inject_instance_metadata(self):
-        class FakeMetaItem(object):
-            def __init__(self, key, value):
-                self.key = key
-                self.value = value
 
         # Add some system_metadata to ensure it doesn't get added
         # to xenstore
-        instance = dict(metadata=[FakeMetaItem("a", 1),
-                                  FakeMetaItem("b", 2),
-                                  FakeMetaItem("c", 3),
+        instance = dict(metadata=[{'key': 'a', 'value': 1},
+                                  {'key': 'b', 'value': 2},
+                                  {'key': 'c', 'value': 3},
                                   # Check xenstore key sanitizing
-                                  FakeMetaItem("hi.there", 4),
-                                  FakeMetaItem("hi!t.e/e", 5)],
-                        system_metadata=[FakeMetaItem("sys_a", 1),
-                                         FakeMetaItem("sys_b", 2),
-                                         FakeMetaItem("sys_c", 3)])
+                                  {'key': 'hi.there', 'value': 4},
+                                  {'key': 'hi!t.e/e', 'value': 5}],
+                                  # Check xenstore key sanitizing
+                        system_metadata=[{'key': 'sys_a', 'value': 1},
+                                         {'key': 'sys_b', 'value': 2},
+                                         {'key': 'sys_c', 'value': 3}])
         self.conn._vmops.inject_instance_metadata(instance, 'vm_ref')
 
         self.assertEqual(self.xenstore, {

nova/virt/xenapi/vmops.py

@@ -852,8 +852,8 @@ def inject_instance_metadata(self, instance, vm_ref):
         """Inject instance metadata into xenstore."""
         def store_meta(topdir, data_list):
             for item in data_list:
-                key = self._sanitize_xenstore_key(item.key)
-                value = item.value or ''
+                key = self._sanitize_xenstore_key(item['key'])
+                value = item['value'] or ''
                 self._add_to_param_xenstore(vm_ref, '%s/%s' % (topdir, key),
                                             jsonutils.dumps(value))