Create Authentication Plugins

Provides the framework for creating authentication plugins and using
them from a session object.

To allow this system to co-exist with the original client there is a bit
of a hack. The client object itself is now also an authentication
plugin, that supports the original client pattern. If a client is
created without a session object then that session object uses the
client as it's authentication plugin.

Change-Id: I682c8dcd3705148aaa804a91f4ed48a5b74bdc12
blueprint: auth-plugins

1 files changed, 4 insertions, 0 deletions

diff --git a/keystoneclient/exceptions.py b/keystoneclient/exceptions.py
index 5254c22..3c56b9a 100644
--- a/keystoneclient/exceptions.py
+++ b/keystoneclient/exceptions.py
@@ -49,3 +49,7 @@ class DiscoveryFailure(ClientException):
 
 class VersionNotAvailable(DiscoveryFailure):
     """Discovery failed as the version you requested is not available."""
+
+
+class MissingAuthPlugin(ClientException):
+    """An authenticated request is required but no plugin available."""