Optimizes ec2 keystone usage and handles errors

 * breaks out gen_request_id so we can return it in error msg
 * breaks out ec2_error so we can use it in multiple middlewares
 * adds new middleware (remove old after devstack change)
 * skips extra call to keystone for second authentication
 * fixes bug 922373

Change-Id: If765d149289255b0bf0e0c1b647ebb547ce5759b

1 files changed, 5 insertions, 2 deletions

diff --git a/nova/context.py b/nova/context.py
index b0c0603a8..dbeb18652 100644
--- a/nova/context.py
+++ b/nova/context.py
@@ -20,12 +20,15 @@
 """RequestContext: context for requests that persist through all of nova."""
 
 import copy
-import uuid
 
 from nova import local
 from nova import utils
 
 
+def generate_request_id():
+    return 'req-' + str(utils.gen_uuid())
+
+
 class RequestContext(object):
     """Security context and request information.
 
@@ -59,7 +62,7 @@ class RequestContext(object):
             timestamp = utils.parse_strtime(timestamp)
         self.timestamp = timestamp
         if not request_id:
-            request_id = 'req-' + str(utils.gen_uuid())
+            request_id = generate_request_id()
         self.request_id = request_id
         self.auth_token = auth_token
         self.strategy = strategy