Internally defined middleware don't use stevedore

For internally defined middleware (URL Normalizer and AuthContext)
Do not use stevedore to load, apply directly. This also cleans up
a lingering entry in the setup.cfg for token_auth.

Test Changes:

* entry points test no longer looks for url_normalize and
build_auth_context

Change-Id: I58d3c23ad4f70668ada4eae94a94d3f5fe750b3b
Partial-Bug: #1776504

keystone/server/flask/core.py

@@ -27,6 +27,7 @@ oslo_i18n.enable_lazy()
 
 from keystone.common import profiler
 import keystone.conf
+import keystone.middleware
 import keystone.server
 from keystone.server.flask import application
 
@@ -51,18 +52,23 @@ _APP_MIDDLEWARE = (
     _Middleware(namespace='keystone.server_middleware',
                 ep='http_proxy_to_wsgi',
                 conf={}),
-    _Middleware(namespace='keystone.server_middleware',
-                ep='url_normalize',
-                conf={}),
     _Middleware(namespace='keystone.server_middleware',
                 ep='osprofiler',
                 conf={}),
     _Middleware(namespace='keystone.server_middleware',
                 ep='request_id',
                 conf={}),
-    _Middleware(namespace='keystone.server_middleware',
-                ep='build_auth_context',
-                conf={}),
+)
+
+# NOTE(morgan): ORDER HERE IS IMPORTANT! Each of these middlewares are
+# implemented/defined explicitly in Keystone Server. They do some level of
+# lifting to ensure the request is properly handled. It is importat to note
+# that these will be processed in the order of this list AND after all
+# middleware defined in _APP_MIDDLEWARE. AuthContextMiddleware should always
+# be the last element here as long as it is an actual Middleware.
+_KEYSTONE_MIDDLEWARE = (
+    keystone.middleware.NormalizingFilter,
+    keystone.middleware.AuthContextMiddleware,
 )
 
 
@@ -89,6 +95,7 @@ def setup_app_middleware(app):
     # processes the request first.
 
     MW = _APP_MIDDLEWARE
+    IMW = _KEYSTONE_MIDDLEWARE
 
     # Add in optional (config-based) middleware
     # NOTE(morgan): Each of these may need to be in a specific location
@@ -99,6 +106,11 @@ def setup_app_middleware(app):
                           ep='debug',
                           conf={}),) + _APP_MIDDLEWARE
 
+    # Apply internal-only Middleware (e.g. AuthContextMiddleware). These
+    # are below all externally loaded middleware in request processing.
+    for mw in reversed(IMW):
+        app.wsgi_app = mw(app.wsgi_app)
+
     # Apply the middleware to the application.
     for mw in reversed(MW):
         # TODO(morgan): Explore moving this to ExtensionManager, but we

keystone/tests/unit/test_entry_points.py

@@ -20,12 +20,10 @@ class TestEntryPoints(test.TestCase):
     def test_entry_point_middleware(self):
         """Assert that our list of expected middleware is present."""
         expected_names = [
-            'build_auth_context',
             'cors',
             'debug',
             'request_id',
             'sizelimit',
-            'url_normalize',
         ]
 
         em = stevedore.ExtensionManager('keystone.server_middleware')

setup.cfg

@@ -192,8 +192,5 @@ keystone.server_middleware =
     sizelimit = oslo_middleware:RequestBodySizeLimiter
     http_proxy_to_wsgi = oslo_middleware:HTTPProxyToWSGI
     osprofiler = osprofiler.web:WsgiMiddleware
-    url_normalize = keystone.middleware:NormalizingFilter
     request_id = oslo_middleware:RequestId
-    build_auth_context = keystone.middleware:AuthContextMiddleware
-    token_auth = keystone.middleware:TokenAuthMiddleware
     debug = oslo_middleware:Debug