python observer pattern example

observer.py

import pdb
import time
import threading

class Event(object):
    pass

class Observable(object):
    def __init__(self):
        self.callbacks = []
    def encode(self):
        print 'ENCODE'
    def subscribe(self, callback):
        self.callbacks.append(callback)
    def fire(self, **attrs):
        e = Event()
        e.source = self
        for k, v in attrs.iteritems():
            setattr(e, k, v)
        for fn in self.callbacks:
            fn(e)

class Logger(threading.Thread):

    def __init__(self):
        print 'init Logger'
        threading.Thread.__init__(self)

    def alert(self, event):
        print 'ALERT', event.msg

    def run(self):
        while True:
            time.sleep(1)

log = Logger()
#log.start()

class Encoder(Observable):

    def encode(self):
        print 'adsfasdf'
        super(Encoder, self).encode()
    #Log = Observable()


t = Encoder()

pdb.set_trace()

observer_worker.py

import threading
import time
import pdb

class Downloader(threading.Thread):

    def run(self):
        print 'downloading'
        for i in range(1,5):
            self.i = i
            time.sleep(2)
        print 'unfunf'
        return 'hello world'

class Worker(threading.Thread):

    def run(self):
        for i in range(1,5):
            print 'worker running: %i (%i)' % (i, t.i)
            time.sleep(1)
            t.join()

        print 'done'

t = Downloader()
t.start()

time.sleep(1)

t1 = Worker()
t1.start()

t2 = Worker()
t2.start()

t3 = Worker()
t3.start()