Provide backoff context managers

[OddBloke]

I sometimes have a third-party function or method that I would like to retry using backoff. Currently, I have to wrap the call in a single line function and decorate that. It would be nice if I could, instead, use a context manager.

So what I currently do is:

def do_a_thing(...):
    @backoff.on_exception(...)
    def _actually_do_third_party_thing():
        _do_third_party_thing()

    some_setup()
    _actually_do_third_party_thing()
    some_teardown()

And what I'd like to be able to do:

def do_a_thing(...):
    some_setup()
    with backoff.on_exception(...):
        _do_third_party_thing()
    some_teardown()

[OddBloke]

I've spent a bit of time digging in to this, and I think it's actually impossible to do with the context manager semantics as they currently exist.

Specifically, there's no way to re-execute the body of a with statement, which is pretty important in this context[0].

[0] https://mail.python.org/pipermail/python-ideas/2013-May/020633.html

[bgreen-litl]

This has come up before and there is some ongoing discussion here #18

And you are correct that this can't be done as originally suggested. We've talked about a few variants of this idea but I've never quite been able to make it work in a way that is a clear improvement to the status quo. FWIW, in the case where you are calling that 3rd party function in a single place, I recommend the decorating the function inline (as you do in your example above) as a best practice.