Python external epoll loop example with Proton 0.7 RC

external_epoll_loop.py

import select

from proton import Message
from proton import Messenger

known_selectables = {}

def epoll_events(sel):
    events = 0
    if sel.capacity > 0:
        events |= select.EPOLLIN
    if sel.pending > 0:
        events |= select.EPOLLOUT
    return events

def update_selectables(my_epoll, m):
    while True:
        sel = m.selectable()
        if sel is None:
            break
        fileno = sel.fileno()
        if not sel.registered:
            my_epoll.register(fileno, epoll_events(sel))
            known_selectables[fileno] = sel
            sel.registered = True
        else:
            my_epoll.modify(fileno, epoll_events(sel))
        if sel.is_terminal:
            my_epoll.unregister(fileno)
            known_selectables.pop(fileno)
            sel.free()



def main():
    my_epoll = select.epoll()

    m = Messenger()
    m.passive = True

    msg = Message()
    msg.address = "amqp://127.0.0.1/queuename"
    msg.body = u"Hello World"
    m.put(msg)

    while True:
        update_selectables(my_epoll, m)
        if m.deadline:
            epoll_events = my_epoll.poll(timeout=m.deadline)
        else:
            epoll_events = my_epoll.poll()
        if epoll_events:
            for fd, eventmask in epoll_events:
                sel = known_selectables[fd]
                if eventmask & select.EPOLLOUT:
                    sel.writable()
                if eventmask & select.EPOLLIN:
                    sel.readable()



if __name__ == "__main__":
    main()