I've got an application that runs Twisted by starting the reactor with reactor.run()
in my main thread after starting some other threads, including the CherryPy web server. Here's a program that shuts down cleanly when Ctrl+C is pressed on Linux but not on Windows:
from threading import Thread
from signal import signal, SIGINTimport cherrypyfrom twisted.internet import reactor
from twisted.web.client import getPagedef stop(signum, frame):cherrypy.engine.exit()reactor.callFromThread(reactor.stop)
signal(SIGINT, stop)class Root:@cherrypy.exposedef index(self):reactor.callFromThread(kickoff)return "Hello World!"cherrypy.server.socket_host = "0.0.0.0"
Thread(target=cherrypy.quickstart, args=[Root()]).start()def print_page(html):print(html)def kickoff():getPage("http://acpstats/account/login").addCallback(print_page)reactor.run()
I believe that CherryPy is the culprit here, because here's a different program that I wrote without CherryPy that does shutdown cleanly on both Linux and Windows when Ctrl+C is pressed:
from time import sleep
from threading import Thread
from signal import signal, SIGINTfrom twisted.internet import reactor
from twisted.web.client import getPagekeep_going = True
def stop(signum, frame):global keep_goingkeep_going = Falsereactor.callFromThread(reactor.stop)
signal(SIGINT, stop)def print_page(html):print(html)def kickoff():getPage("http://acpstats/account/login").addCallback(print_page)def periodic_downloader():while keep_going:reactor.callFromThread(kickoff)sleep(5)Thread(target=periodic_downloader).start()
reactor.run()
Does anyone have any idea what the problem is? Here's my conundrum:
- On Linux everything works
- On Windows, I can call functions from signal handlers using
reactor.callFromThread
when CherryPy is not running - When CherryPy is running, no function that I call using
reactor.callFromThread
from a signal handler will ever execute (I've verified that the signal handler itself does get called)
What can I do about this? How can I shut down Twisted on Windows from a signal handler while running CherryPy? Is this a bug, or have I simply missed some important part of the documentation for either of these two projects?