Make AuthContext depend on auth_token middleware

Reuse the validation logic that is already present in auth_token
middleware. Once this is present keystone can start to reuse the same
helpers that are created from auth_token middleware that the other
services rely on.

For now there is still some redundancy, like for example bind checking
is now enforced in auth_token middleware and in keystone. These can be
removed in later commits because they will require test changes.

My intention after this is to start to more directly integrate this with
oslo.policy and start to standardize the way auth is handled from
auth_token middleware to enforcement. Doing this work here means that we
get keystone to try out policy changes first.

Change-Id: I6592ea2865863c9ace1304b06d73a917c3a1b114

1 files changed, 31 insertions, 20 deletions

diff --git a/keystone/common/wsgi.py b/keystone/common/wsgi.py
index 04528a0c0..53cb5631e 100644
--- a/keystone/common/wsgi.py
+++ b/keystone/common/wsgi.py
@@ -19,6 +19,7 @@
 """Utility methods for working with WSGI servers."""
 
 import copy
+import functools
 import itertools
 import re
 import wsgiref.util
@@ -393,6 +394,30 @@ class Application(BaseApplication):
         return url.rstrip('/')
 
 
+def middleware_exceptions(method):
+
+    @functools.wraps(method)
+    def _inner(self, request):
+        try:
+            return method(self, request)
+        except exception.Error as e:
+            LOG.warning(six.text_type(e))
+            return render_exception(e, request=request,
+                                    user_locale=best_match_language(request))
+        except TypeError as e:
+            LOG.exception(six.text_type(e))
+            return render_exception(exception.ValidationError(e),
+                                    request=request,
+                                    user_locale=best_match_language(request))
+        except Exception as e:
+            LOG.exception(six.text_type(e))
+            return render_exception(exception.UnexpectedError(exception=e),
+                                    request=request,
+                                    user_locale=best_match_language(request))
+
+    return _inner
+
+
 class Middleware(Application):
     """Base WSGI middleware.
 
@@ -429,27 +454,13 @@ class Middleware(Application):
         return response
 
     @webob.dec.wsgify()
+    @middleware_exceptions
     def __call__(self, request):
-        try:
-            response = self.process_request(request)
-            if response:
-                return response
-            response = request.get_response(self.application)
-            return self.process_response(request, response)
-        except exception.Error as e:
-            LOG.warning(six.text_type(e))
-            return render_exception(e, request=request,
-                                    user_locale=best_match_language(request))
-        except TypeError as e:
-            LOG.exception(six.text_type(e))
-            return render_exception(exception.ValidationError(e),
-                                    request=request,
-                                    user_locale=best_match_language(request))
-        except Exception as e:
-            LOG.exception(six.text_type(e))
-            return render_exception(exception.UnexpectedError(exception=e),
-                                    request=request,
-                                    user_locale=best_match_language(request))
+        response = self.process_request(request)
+        if response:
+            return response
+        response = request.get_response(self.application)
+        return self.process_response(request, response)
 
 
 class Debug(Middleware):