examples/python/reactor/goodbye-world.py

#!/usr/bin/python
#
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from __future__ import print_function
from proton.reactor import Reactor

# So far the reactive hello-world doesn't look too different from a
# regular old non-reactive hello-world. The on_reactor_init method can
# be used roughly as a 'main' method would. A program that only uses
# that one event, however, isn't going to be very reactive. By using
# other events, we can write a fully reactive program.

class Program:

    # As before we handle the reactor init event.
    def on_reactor_init(self, event):
        print("Hello, World!")

    # In addition to an initial event, the reactor also produces an
    # event when it is about to exit. This may not behave much
    # differently than just putting the goodbye print statement inside
    # on_reactor_init, but as we grow our program, this piece of it
    # will always be what happens last, and will always happen
    # regardless of what other paths the main logic of our program
    # might take.
    def on_reactor_final(self, event):
        print("Goodbye, World!")

r = Reactor(Program())
r.run()