Merge "Adds check that the core V3 API is loaded"

1 files changed, 20 insertions, 0 deletions

diff --git a/nova/api/openstack/__init__.py b/nova/api/openstack/__init__.py
index 3687ce111..3455b812d 100644
--- a/nova/api/openstack/__init__.py
+++ b/nova/api/openstack/__init__.py
@@ -28,6 +28,7 @@ import webob.exc
 
 from nova.api.openstack import extensions
 from nova.api.openstack import wsgi
+from nova import exception
 from nova import notifications
 from nova.openstack.common import log as logging
 from nova import utils
@@ -55,6 +56,11 @@ CONF = cfg.CONF
 CONF.register_group(api_opts_group)
 CONF.register_opts(api_opts, api_opts_group)
 
+# List of v3 API extensions which are considered to form
+# the core API and so must be present
+# TODO(cyeoh): Expand this list as the core APIs are ported to V3
+API_V3_CORE_EXTENSIONS = set(['servers'])
+
 
 class FaultWrapper(base_wsgi.Middleware):
     """Calls down the middleware stack, making exceptions into faults."""
@@ -306,8 +312,22 @@ class APIRouterV3(base_wsgi.Router):
                                            mapper=mapper)
             self.api_extension_manager.map(self._register_controllers)
 
+        missing_core_extensions = self.get_missing_core_extensions(
+            self.loaded_extension_info.get_extensions().keys())
+        if missing_core_extensions:
+            LOG.critical(_("Missing core API extensions: %s"),
+                         missing_core_extensions)
+            raise exception.CoreAPIMissing(
+                missing_apis=missing_core_extensions)
+
         super(APIRouterV3, self).__init__(mapper)
 
+    @staticmethod
+    def get_missing_core_extensions(extensions_loaded):
+        extensions_loaded = set(extensions_loaded)
+        missing_extensions = API_V3_CORE_EXTENSIONS - extensions_loaded
+        return missing_extensions
+
     @property
     def loaded_extension_info(self):
         raise NotImplementedError()