Do not raise NEW exceptions

Raising NEW exception is bad practice, because we lose TraceBack.
So all places like:

except SomeException as e:
    raise e

should be replaced by

except SomeException:
    raise

If we are doing some other actions before reraising we should
store information about exception then do all actions and then
reraise it. This is caused by eventlet bug. It lost information
about exception if it switch threads.

fixes bug 1191730

Change-Id: Ia375ecef9f16bda65d5146d14ed4b37a988abb0c

1 files changed, 4 insertions, 2 deletions

diff --git a/nova/exception.py b/nova/exception.py
index 68cf1f991..002e47a38 100644
--- a/nova/exception.py
+++ b/nova/exception.py
@@ -25,6 +25,7 @@ SHOULD include dedicated exception logging.
 """
 
 import functools
+import sys
 
 from oslo.config import cfg
 import webob.exc
@@ -127,7 +128,8 @@ class NovaException(Exception):
             try:
                 message = self.message % kwargs
 
-            except Exception as e:
+            except Exception:
+                exc_info = sys.exc_info()
                 # kwargs doesn't match a variable in the message
                 # log the issue and the kwargs
                 LOG.exception(_('Exception in string format operation'))
@@ -135,7 +137,7 @@ class NovaException(Exception):
                     LOG.error("%s: %s" % (name, value))
 
                 if CONF.fatal_exception_format_errors:
-                    raise e
+                    raise exc_info[0], exc_info[1], exc_info[2]
                 else:
                     # at least get the core message out if something happened
                     message = self.message