catch errors in wsgi.Middleware.

- Catch errors in wsgi.Middleware like done in wsgi.Applications.
- Add tests for test_middleware.
- Fixes bug 1128379.

Change-Id: I2e95595c392631aebf2682d4506e4dde78cd6d69

keystone/common/wsgi.py

@@ -347,11 +347,21 @@ def process_response(self, request, response):
 
     @webob.dec.wsgify(RequestClass=Request)
     def __call__(self, request):
-        response = self.process_request(request)
-        if response:
-            return response
-        response = request.get_response(self.application)
-        return self.process_response(request, response)
+        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(e)
+            return render_exception(e)
+        except TypeError as e:
+            LOG.exception(e)
+            return render_exception(exception.ValidationError(e))
+        except Exception as e:
+            LOG.exception(e)
+            return render_exception(exception.UnexpectedError(exception=e))
 
 
 class Debug(Middleware):

tests/test_wsgi.py

@@ -19,33 +19,38 @@
 from keystone.common import wsgi
 from keystone.openstack.common import jsonutils
 from keystone import test
+from keystone import exception
 
 
-class ApplicationTest(test.TestCase):
+class FakeApp(wsgi.Application):
+    def index(self, context):
+        return {'a': 'b'}
+
+
+class BaseWSGITest(test.TestCase):
+    def setUp(self):
+        self.app = FakeApp()
+        super(BaseWSGITest, self).setUp()
+
     def _make_request(self, url='/'):
         req = webob.Request.blank(url)
         args = {'action': 'index', 'controller': None}
         req.environ['wsgiorg.routing_args'] = [None, args]
         return req
 
-    def test_response_content_type(self):
-        class FakeApp(wsgi.Application):
-            def index(self, context):
-                return {'a': 'b'}
 
-        app = FakeApp()
+class ApplicationTest(BaseWSGITest):
+    def test_response_content_type(self):
         req = self._make_request()
-        resp = req.get_response(app)
+        resp = req.get_response(self.app)
         self.assertEqual(resp.content_type, 'application/json')
 
     def test_query_string_available(self):
         class FakeApp(wsgi.Application):
             def index(self, context):
                 return context['query_string']
-
-        app = FakeApp()
         req = self._make_request(url='/?1=2')
-        resp = req.get_response(app)
+        resp = req.get_response(FakeApp())
         self.assertEqual(jsonutils.loads(resp.body), {'1': '2'})
 
     def test_render_response(self):
@@ -76,3 +81,55 @@ def test_render_response_no_body(self):
         self.assertEqual(resp.body, '')
         self.assertEqual(resp.headers.get('Content-Length'), '0')
         self.assertEqual(resp.headers.get('Content-Type'), None)
+
+
+class MiddlewareTest(BaseWSGITest):
+    def test_middleware_request(self):
+        class FakeMiddleware(wsgi.Middleware):
+            def process_request(self, req):
+                req.environ['fake_request'] = True
+                return req
+        req = self._make_request()
+        resp = FakeMiddleware(None)(req)
+        self.assertIn('fake_request', resp.environ)
+
+    def test_middleware_response(self):
+        class FakeMiddleware(wsgi.Middleware):
+            def process_response(self, request, response):
+                response.environ = {}
+                response.environ['fake_response'] = True
+                return response
+        req = self._make_request()
+        resp = FakeMiddleware(self.app)(req)
+        self.assertIn('fake_response', resp.environ)
+
+    def test_middleware_bad_request(self):
+        class FakeMiddleware(wsgi.Middleware):
+            def process_response(self, request, response):
+                raise exception.Unauthorized()
+
+        req = self._make_request()
+        req.environ['REMOTE_ADDR'] = '127.0.0.1'
+        resp = FakeMiddleware(self.app)(req)
+        self.assertEquals(resp.status_int, exception.Unauthorized.code)
+
+    def test_middleware_type_error(self):
+        class FakeMiddleware(wsgi.Middleware):
+            def process_response(self, request, response):
+                raise TypeError()
+
+        req = self._make_request()
+        req.environ['REMOTE_ADDR'] = '127.0.0.1'
+        resp = FakeMiddleware(self.app)(req)
+        # This is a validationerror type
+        self.assertEquals(resp.status_int, exception.ValidationError.code)
+
+    def test_middleware_exception_error(self):
+        class FakeMiddleware(wsgi.Middleware):
+            def process_response(self, request, response):
+                raise exception.UnexpectedError("EXCEPTIONERROR")
+
+        req = self._make_request()
+        resp = FakeMiddleware(self.app)(req)
+        self.assertEquals(resp.status_int, exception.UnexpectedError.code)
+        self.assertIn("EXCEPTIONERROR", resp.body)