Comment 0 for bug 845866

Since switching the db code to use an eventlet library, we can no longer re-raise exceptions if there is any db access in the exception handler. There are a number of places in the code where this is done.

we need to change instances of

except <SomeException>:
  # code that uses db or rpc
  raise

to:

except <SomeException>:
  exc = sys.exc_info()
  # code that uses db or rpc
  raise exc

Also adding a logging.exception('useful message') is probably a good idea in most cases if the original traceback is important.