python signal blinker

foo.py

from blinker import signal


def subscriber(sender):
    print("Got a signal send by %r" % sender)


# already have signal, define own receive method
send_data = signal('send-data')


@send_data.connect
def receive_data(sender, **kw):
    print("Caught signal from %r, data %r" % (sender, kw))
    return 'received!'


# already have receive method, define own signal
def receive_data(sender, **kw):
    print("Caught signal from %r, data %r" % (sender, kw))
    return 'received!'


send_data = signal('send-data')
send_data.connect(receive_data)

# send a signal but only receive
dice_roll = signal('dice_roll')
another_dice_roll = signal('another_dice_roll')


# subscriber muti signal with special mark.
@dice_roll.connect_via(1)
@dice_roll.connect_via(3)
@another_dice_roll.connect_via(2)
def odd_subscriber(sender):
    print("Observed dice roll %r." % sender)


dice_roll.send(3)
dice_roll.send(2)
another_dice_roll.send(1)
another_dice_roll.send(2)

主要差别发布者和订阅者的绑定方式。根据功能的调用方向可以灵活使用。