gistfile1.txt

class AtFuncExit(object):

    """Similar to Go-lang's defer keyword. Allows execution of a list of
    functions at a block exit boundary.
    """

    def __init__(self, swallow_errors=False, fifo=False):
        self._exception_calls = []
        self._normal_calls = []
        self._swallow_errors = swallow_errors
        self._fifo = fifo

    def __enter__(self):
        return self

    def add_to_except(self, call, *args, **kwargs):
        self._exception_calls.append((call, args, kwargs))

    def add(self, call, *args, **kwargs):
        self._normal_calls.append((call, args, kwargs))

    def add_to_both(self, call, *args, **kwargs):
        self._normal_calls.append((call, args, kwargs))
        self._exception_calls.append((call, args, kwargs))

    def __exit__(self, exc_type, exc_value, traceback):
        if exc_type is None:
            call_list = self._normal_calls
        else:
            call_list = self._exception_calls
        if not self._fifo:
            call_list = reversed(call_list)
        for call, args, kwargs in call_list:
            try:
                call(*args, **kwargs)
            except Exception, e:
                if not self._swallow_errors:
                    raise e
                logger.error("%s", e)