examples/python/reactor/delegates.py

#!/usr/bin/python
#
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# to you under the Apache License, Version 2.0 (the
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# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
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from __future__ import print_function
import time
from proton.reactor import Reactor

# Events know how to dispatch themselves to handlers. By combining
# this with on_unhandled, you can provide a kind of inheritance
# between handlers using delegation.

class Hello:

    def on_reactor_init(self, event):
        print("Hello, World!")

class Goodbye:

    def on_reactor_final(self, event):
        print("Goodbye, World!")

class Program:

    def __init__(self, *delegates):
        self.delegates = delegates

    def on_unhandled(self, name, event):
        for d in self.delegates:
            event.dispatch(d)

r = Reactor(Program(Hello(), Goodbye()))
r.run()