Make image props filter handle old vm_modes

The ImagePropertyFilter would fail to build an instance if the image
used an older style vm_mode (e.g. 'pv') as described in
nova.compute.vm_mode.  This change will convert the vm mode string to
the current form.

Change-Id: Ibde37e28b02d9e866b286ea14c47a6a8411d94b4
Closes-Bug: #1276773

nova/compute/vm_mode.py

@@ -37,7 +37,10 @@ ALL = [HVM, XEN, UML, EXE]
 
 def get_from_instance(instance):
     mode = instance['vm_mode']
+    return name(mode)
 
+
+def name(mode):
     if mode is None:
         return None
 

nova/scheduler/filters/image_props_filter.py

@@ -16,6 +16,7 @@
 #    under the License.
 from distutils import versionpredicate
 
+from nova.compute import vm_mode
 from nova.openstack.common.gettextutils import _
 from nova.openstack.common import log as logging
 from nova.scheduler import filters
@@ -43,6 +44,7 @@ class ImagePropertiesFilter(filters.BaseHostFilter):
         img_arch = image_props.get('architecture', None)
         img_h_type = image_props.get('hypervisor_type', None)
         img_vm_mode = image_props.get('vm_mode', None)
+        img_vm_mode = vm_mode.name(img_vm_mode)  # get canonical name
         checked_img_props = (img_arch, img_h_type, img_vm_mode)
 
         # Supported if no compute-related instance properties are specified

nova/tests/compute/test_vmmode.py

@@ -45,3 +45,22 @@ class ComputeVMModeTest(test.NoDBTestCase):
         inst = dict(vm_mode="hvm")
         mode = vm_mode.get_from_instance(inst)
         self.assertEqual(mode, "hvm")
+
+    def test_name_pv_compat(self):
+        mode = vm_mode.name('pv')
+        self.assertEqual(vm_mode.XEN, mode)
+
+    def test_name_hv_compat(self):
+        mode = vm_mode.name('hv')
+        self.assertEqual(vm_mode.HVM, mode)
+
+    def test_name_hvm(self):
+        mode = vm_mode.name('hvm')
+        self.assertEqual(vm_mode.HVM, mode)
+
+    def test_name_none(self):
+        mode = vm_mode.name(None)
+        self.assertEqual(None, mode)
+
+    def test_name_invalid(self):
+        self.assertRaises(exception.Invalid, vm_mode.name, 'invalid')

nova/tests/scheduler/test_host_filters.py

@@ -34,6 +34,7 @@ from nova.tests.scheduler import fakes
 from nova import utils
 
 CONF = cfg.CONF
+
 CONF.import_opt('my_ip', 'nova.netconf')
 
 
@@ -779,6 +780,30 @@ class HostFiltersTestCase(test.NoDBTestCase):
         host = fakes.FakeHostState('host1', 'node1', capabilities)
         self.assertFalse(filt_cls.host_passes(host, filter_properties))
 
+    def test_image_properties_filter_pv_mode_compat(self):
+        # if an old image has 'pv' for a vm_mode it should be treated as xen
+        self._stub_service_is_up(True)
+        filt_cls = self.class_map['ImagePropertiesFilter']()
+        img_props = {'properties': {'vm_mode': 'pv'}}
+        filter_properties = {'request_spec': {'image': img_props}}
+        hypervisor_version = utils.convert_version_to_int('6.0.0')
+        capabilities = {'supported_instances': [('x86_64', 'xapi', 'xen')],
+                        'hypervisor_version': hypervisor_version}
+        host = fakes.FakeHostState('host1', 'node1', capabilities)
+        self.assertTrue(filt_cls.host_passes(host, filter_properties))
+
+    def test_image_properties_filter_hvm_mode_compat(self):
+        # if an old image has 'hv' for a vm_mode it should be treated as xen
+        self._stub_service_is_up(True)
+        filt_cls = self.class_map['ImagePropertiesFilter']()
+        img_props = {'properties': {'vm_mode': 'hv'}}
+        filter_properties = {'request_spec': {'image': img_props}}
+        hypervisor_version = utils.convert_version_to_int('6.0.0')
+        capabilities = {'supported_instances': [('x86_64', 'kvm', 'hvm')],
+                        'hypervisor_version': hypervisor_version}
+        host = fakes.FakeHostState('host1', 'node1', capabilities)
+        self.assertTrue(filt_cls.host_passes(host, filter_properties))
+
     def _do_test_compute_filter_extra_specs(self, ecaps, especs, passes):
         """In real Openstack runtime environment,compute capabilities
         value may be number, so we should use number to do unit test.