Blinker

Blinker provides a fast dispatching system that allows any number of interested parties to subscribe to events, or "signals".

Pallets Community Ecosystem

[!IMPORTANT]
This project is part of the Pallets Community Ecosystem. Pallets is the open source organization that maintains Flask; Pallets-Eco enables community maintenance of related projects. If you are interested in helping maintain this project, please reach out on the Pallets Discord server.

Example

Signal receivers can subscribe to specific senders or receive signals sent by any sender.

>>> from blinker import signal
>>> started = signal('round-started')
>>> def each(round):
...     print(f"Round {round}")
...
>>> started.connect(each)

>>> def round_two(round):
...     print("This is round two.")
...
>>> started.connect(round_two, sender=2)

>>> for round in range(1, 4):
...     started.send(round)
...
Round 1!
Round 2!
This is round two.
Round 3!