Merge "Do not raise NEW exceptions"

3 files changed, 13 insertions, 3 deletions

diff --git a/HACKING.rst b/HACKING.rst
index 3cea316..846c1b1 100644
--- a/HACKING.rst
+++ b/HACKING.rst
@@ -46,6 +46,16 @@ General
         pass
 
 
+- Use 'raise' instead of 'raise e' to preserve original traceback or exception being reraised::
+
+    except Exception as e:
+        ...
+        raise e  # BAD
+
+    except Exception:
+        ...
+        raise  # OKAY
+
 TODO vs FIXME
 -------------
 
diff --git a/openstack/common/exception.py b/openstack/common/exception.py
index cdf40f3..f6c8463 100644
--- a/openstack/common/exception.py
+++ b/openstack/common/exception.py
@@ -122,9 +122,9 @@ class OpenstackException(Exception):
         try:
             self._error_string = self.message % kwargs
 
-        except Exception as e:
+        except Exception:
             if _FATAL_EXCEPTION_FORMAT_ERRORS:
-                raise e
+                raise
             else:
                 # at least get the core message out if something happened
                 self._error_string = self.message
diff --git a/tests/unit/rpc/test_common.py b/tests/unit/rpc/test_common.py
index c2432f4..6f32005 100644
--- a/tests/unit/rpc/test_common.py
+++ b/tests/unit/rpc/test_common.py
@@ -108,7 +108,7 @@ class RpcCommonTestCase(test_utils.BaseTestCase):
                                     '__unicode__': str_override})
                 new_ex_type.__module__ = '%s_Remote' % e.__class__.__module__
                 e.__class__ = new_ex_type
-                raise e
+                raise
 
         try:
             raise_remote_exception()