1 files changed, 72 insertions, 0 deletions
diff --git a/cyborg_enhancement/mitaka_version/cyborg/cyborg/api/middleware/parsable_error.py b/cyborg_enhancement/mitaka_version/cyborg/cyborg/api/middleware/parsable_error.py
new file mode 100644
index 0000000..ba80c22
--- /dev/null
+++ b/cyborg_enhancement/mitaka_version/cyborg/cyborg/api/middleware/parsable_error.py
@@ -0,0 +1,72 @@
+# Copyright 2017 Huawei Technologies Co.,LTD.
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""
+Middleware to replace the plain text message body of an error
+response with one formatted so the client can parse it.
+
+Based on pecan.middleware.errordocument
+"""
+
+import json
+
+import six
+
+
+class ParsableErrorMiddleware(object):
+    """Replace error body with something the client can parse."""
+    def __init__(self, app):
+        self.app = app
+
+    def __call__(self, environ, start_response):
+        # Request for this state, modified by replace_start_response()
+        # and used when an error is being reported.
+        state = {}
+
+        def replacement_start_response(status, headers, exc_info=None):
+            """Overrides the default response to make errors parsable."""
+            try:
+                status_code = int(status.split(' ')[0])
+                state['status_code'] = status_code
+            except (ValueError, TypeError):  # pragma: nocover
+                raise Exception(
+                    'ParsableErrorMiddleware received an invalid '
+                    'status %s' % status)
+
+            if (state['status_code'] // 100) not in (2, 3):
+                # Remove some headers so we can replace them later
+                # when we have the full error message and can
+                # compute the length.
+                headers = [
+                    (h, v) for (h, v) in headers
+                    if h not in ('Content-Length', 'Content-Type')]
+
+            # Save the headers in case we need to modify them.
+            state['headers'] = headers
+            return start_response(status, headers, exc_info)
+
+        app_iter = self.app(environ, replacement_start_response)
+
+        if (state['status_code'] // 100) not in (2, 3):
+            if six.PY3:
+                app_iter = [i.decode('utf-8') for i in app_iter]
+            body = [json.dumps({'error_message': '\n'.join(app_iter)})]
+            if six.PY3:
+                body = [i.encode('utf-8') for i in body]
+            state['headers'].append(('Content-Type', 'application/json'))
+            state['headers'].append(('Content-Length', str(len(body[0]))))
+        else:
+            body = app_iter
+        return body