In response to http://emptysqua.re/blog/tornado-locks-and-queues/

test_condition.py

#!/usr/bin/env python


from __future__ import print_function

from circuits import Component, Debugger, Event


class condition(Event):
    """condition Event"""


class waiter(Event):
    """waiter Event"""


class notifier(Event):
    """notifier Event"""


class App(Component):

    def started(self, *args):
        self.fire(waiter())
        yield

        self.fire(notifier())
        yield

        raise SystemExit(0)

    def waiter(self):
        print("I'll wait right here")
        yield self.wait("condition")
        print("I'm done waiting")

    def notifier(self):
        print("About to notify")
        self.fire(condition())
        print("Done notifying")

    def generate_events(self, event):
        print(".")
        event.reduce_time_left(0.1)


(App() + Debugger()).run()

test_queue.py

#!/usr/bin/env python


from __future__ import print_function

from circuits import Component, Debugger, Event


class producer(Event):
    """producer Event"""


class work(Event):
    """work Event"""


class Consumer(Component):

    def work(self, i):
        print("Doing work on {0:d}".format(i))
        # XXX: We don't have an asynchronous sleep() :)


class App(Component):

    def started(self, *args):
        Consumer().register(self)

        self.fire(producer())
        yield

        raise SystemExit(0)

    def producer(self):
        for i in range(4):
            self.fire(work(i))
            print("Put {0:d}".format(i))


(App() + Debugger()).run()

Demo:

#!bash
$ ./test_condition.py 
<registered[*] (<Debugger/* 17139:MainThread (queued=0) [S]>, <App/* 17139:MainThread (queued=2) [R]> )>
<started[*] (<App/* 17139:MainThread (queued=1) [R]> )>
.
<waiter[*] ( )>
.
I'll wait right here
<notifier[*] ( )>
About to notify
Done notifying
.
<condition[*] ( )>
<stopped[*] (<App/* 17139:MainThread (queued=1) [S]> )>
<condition_done[*] (None )>
I'm done waiting

Updated

Demo of test_queue:

#!bash
$ ./test_queue.py 
<registered[*] (<Debugger/* 19046:MainThread (queued=0) [S]>, <App/* 19046:MainThread (queued=2) [R]> )>
<started[*] (<App/* 19046:MainThread (queued=1) [R]> )>
<registered[*] (<Consumer/* 19046:MainThread (queued=0) [S]>, <App/* 19046:MainThread (queued=2) [R]> )>
<producer[*] ( )>
Put 0
Put 1
Put 2
Put 3
<work[*] (0 )>
Doing work on 0
<work[*] (1 )>
Doing work on 1
<work[*] (2 )>
Doing work on 2
<work[*] (3 )>
Doing work on 3
<stopped[*] (<App/* 19046:MainThread (queued=0) [S]> )>

And just for good measure; we're just implemented [async sleep] for circuits: circuits/circuits#62