Implement API for interactive exec

[TomasTomecek]

Needed for: d11wtq/dockerpty#30
Transitively for: docker/compose#2023

[dnephin]

This does follow the pattern established by attach()/attach_socket() but I wonder if it could be just another kwarg like stream?

What do you think @shin- ?

def exec_start(self, exec_id, detach=False, tty=False, stream=False, socket=False):
    ...
    func = get_response_handler(stream, socket)
    return func(res)

def get_response_handler(stream, socket):
    if stream and socket:
        raise ValueError(...)

    if stream:
        return functools.partial(self._get_result_tty, True)
    if socket:
        return  self._get_raw_response_socket
    return  functools.partial(self._get_result_tty, False)

[TomasTomecek]

Makes sense to me. To be honest, I actually vote for socket=False since there is already an option for asking for stream. On top of it, you'll get this feature for free in future (for new similar API calls).

[TomasTomecek]

@shin- waiting for your reply before I start rewriting.

[shin-]

Yes, socket as a param makes a lot of sense. 👍