Merge "Add the ability to load a set of service plugins on startup"

neutron/api/extensions.py

@@ -30,6 +30,7 @@ from neutron._i18n import _, _LE, _LI, _LW
 from neutron.common import exceptions
 import neutron.extensions
 from neutron import manager
+from neutron.plugins.common import constants as const
 from neutron.services import provider_configuration
 from neutron import wsgi
 
@@ -440,11 +441,18 @@ class ExtensionManager(object):
                 # Exit loop as no progress was made
                 break
         if exts_to_process:
-            LOG.error(_LE("It was impossible to process the following "
-                          "extensions: %s because of missing requirements."),
-                      ','.join(exts_to_process.keys()))
-            raise exceptions.ExtensionsNotFound(
-                extensions=list(exts_to_process.keys()))
+            unloadable_extensions = set(exts_to_process.keys())
+            LOG.error(_LE("Unable to process extensions (%s) because "
+                          "the configured plugins do not satisfy "
+                          "their requirements. Some features will not "
+                          "work as expected."),
+                      ', '.join(unloadable_extensions))
+            # Fail gracefully for default extensions, just in case some out
+            # of tree plugins are not entirely up to speed
+            default_extensions = set(const.DEFAULT_SERVICE_PLUGINS.values())
+            if not unloadable_extensions <= default_extensions:
+                raise exceptions.ExtensionsNotFound(
+                    extensions=list(unloadable_extensions))
 
         # Extending extensions' attributes map.
         for ext in processed_exts.values():

neutron/manager.py

@@ -161,6 +161,10 @@ class NeutronManager(object):
                 LOG.info(_LI("Service %s is supported by the core plugin"),
                          service_type)
 
+    def _get_default_service_plugins(self):
+        """Get default service plugins to be loaded."""
+        return constants.DEFAULT_SERVICE_PLUGINS.keys()
+
     def _load_service_plugins(self):
         """Loads service plugins.
 
@@ -171,6 +175,7 @@ class NeutronManager(object):
         self._load_services_from_core_plugin()
 
         plugin_providers = cfg.CONF.service_plugins
+        plugin_providers.extend(self._get_default_service_plugins())
         LOG.debug("Loading service plugins: %s", plugin_providers)
         for provider in plugin_providers:
             if provider == '':

neutron/plugins/common/constants.py

@@ -38,6 +38,11 @@ EXT_TO_SERVICE_MAPPING = {
     'qos': QOS,
 }
 
+# Maps default service plugins entry points to their extension aliases
+DEFAULT_SERVICE_PLUGINS = {
+    'auto_allocate': 'auto-allocated-topology',
+}
+
 # Service operation status constants
 ACTIVE = "ACTIVE"
 DOWN = "DOWN"

neutron/tests/base.py

@@ -350,6 +350,7 @@ class BaseTestCase(DietTestCase):
         cp = PluginFixture(core_plugin)
         self.useFixture(cp)
         self.patched_dhcp_periodic = cp.patched_dhcp_periodic
+        self.patched_default_svc_plugins = cp.patched_default_svc_plugins
 
     def setup_notification_driver(self, notification_driver=None):
         self.addCleanup(fake_notifier.reset)
@@ -365,6 +366,11 @@ class PluginFixture(fixtures.Fixture):
         self.core_plugin = core_plugin
 
     def _setUp(self):
+        # Do not load default service plugins in the testing framework
+        # as all the mocking involved can cause havoc.
+        self.default_svc_plugins_p = mock.patch(
+            'neutron.manager.NeutronManager._get_default_service_plugins')
+        self.patched_default_svc_plugins = self.default_svc_plugins_p.start()
         self.dhcp_periodic_p = mock.patch(
             'neutron.db.agentschedulers_db.DhcpAgentSchedulerDbMixin.'
             'start_periodic_dhcp_agent_status_check')

neutron/tests/unit/api/test_extensions.py

@@ -502,13 +502,21 @@ class RequestExtensionTest(base.BaseTestCase):
 
 class ExtensionManagerTest(base.BaseTestCase):
 
-    def test_missing_required_extensions(self):
+    def test_missing_required_extensions_raise_error(self):
         ext_mgr = extensions.ExtensionManager('')
         attr_map = {}
         ext_mgr.add_extension(ext_stubs.StubExtensionWithReqs('foo_alias'))
         self.assertRaises(exceptions.ExtensionsNotFound,
                           ext_mgr.extend_resources, "2.0", attr_map)
 
+    def test_missing_required_extensions_gracefully_error(self):
+        ext_mgr = extensions.ExtensionManager('')
+        attr_map = {}
+        default_ext = list(constants.DEFAULT_SERVICE_PLUGINS.values())[0]
+        ext_mgr.add_extension(ext_stubs.StubExtensionWithReqs(default_ext))
+        ext_mgr.extend_resources("2.0", attr_map)
+        self.assertIn(default_ext, ext_mgr.extensions)
+
     def test_invalid_extensions_are_not_registered(self):
 
         class InvalidExtension(object):

neutron/tests/unit/test_manager.py

@@ -111,6 +111,15 @@ class NeutronManagerTestCase(base.BaseTestCase):
         self.assertIn(constants.LOADBALANCER, svc_plugins.keys())
         self.assertIn(constants.DUMMY, svc_plugins.keys())
 
+    def test_load_default_service_plugins(self):
+        self.patched_default_svc_plugins.return_value = {
+            'neutron.tests.unit.dummy_plugin.DummyServicePlugin': 'DUMMY'
+        }
+        cfg.CONF.set_override("core_plugin", DB_PLUGIN_KLASS)
+        mgr = manager.NeutronManager.get_instance()
+        svc_plugins = mgr.get_service_plugins()
+        self.assertIn('DUMMY', svc_plugins)
+
     def test_post_plugin_validation(self):
         cfg.CONF.import_opt('dhcp_agents_per_network',
                             'neutron.db.agentschedulers_db')

releasenotes/notes/add-get-me-a-network-56321aeef5389001.yaml

@@ -0,0 +1,9 @@
+---
+prelude: >
+    The "get-me-a-network" feature simplifies the process
+    for launching an instance with basic network connectivity
+    (via an externally connected private tenant network).
+features:
+  - Once Nova takes advantage of this feature, a user can
+    launch an instance without explicitly provisioning
+    network resources.

setup.cfg

@@ -76,6 +76,7 @@ neutron.service_plugins =
     neutron.services.vpn.plugin.VPNDriverPlugin = neutron_vpnaas.services.vpn.plugin:VPNDriverPlugin
     qos = neutron.services.qos.qos_plugin:QoSPlugin
     flavors = neutron.services.flavors.flavors_plugin:FlavorsPlugin
+    auto_allocate = neutron.services.auto_allocate.plugin:Plugin
 neutron.qos.notification_drivers =
     message_queue = neutron.services.qos.notification_drivers.message_queue:RpcQosServiceNotificationDriver
 neutron.ml2.type_drivers =