Python tornado.ioloop.add_callback_from_signal() Examples

The following are 6 code examples of tornado.ioloop.add_callback_from_signal(). You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may also want to check out all available functions/classes of the module tornado.ioloop , or try the search function .
Example #1
Source File: backend_webagg.py    From Mastering-Elasticsearch-7.0 with MIT License 5 votes vote down vote up 
def start(cls):
        if cls.started:
            return

        """
        IOLoop.running() was removed as of Tornado 2.4; see for example
        https://groups.google.com/forum/#!topic/python-tornado/QLMzkpQBGOY
        Thus there is no correct way to check if the loop has already been
        launched. We may end up with two concurrently running loops in that
        unlucky case with all the expected consequences.
        """
        ioloop = tornado.ioloop.IOLoop.instance()

        def shutdown():
            ioloop.stop()
            print("Server is stopped")
            sys.stdout.flush()
            cls.started = False

        @contextmanager
        def catch_sigint():
            old_handler = signal.signal(
                signal.SIGINT,
                lambda sig, frame: ioloop.add_callback_from_signal(shutdown))
            try:
                yield
            finally:
                signal.signal(signal.SIGINT, old_handler)

        # Set the flag to True *before* blocking on ioloop.start()
        cls.started = True

        print("Press Ctrl+C to stop WebAgg server")
        sys.stdout.flush()
        with catch_sigint():
            ioloop.start()
Example #2
Source File: backend_webagg.py    From GraphicDesignPatternByPython with MIT License 5 votes vote down vote up 
def start(cls):
        if cls.started:
            return

        """
        IOLoop.running() was removed as of Tornado 2.4; see for example
        https://groups.google.com/forum/#!topic/python-tornado/QLMzkpQBGOY
        Thus there is no correct way to check if the loop has already been
        launched. We may end up with two concurrently running loops in that
        unlucky case with all the expected consequences.
        """
        ioloop = tornado.ioloop.IOLoop.instance()

        def shutdown():
            ioloop.stop()
            print("Server is stopped")
            sys.stdout.flush()
            cls.started = False

        @contextmanager
        def catch_sigint():
            old_handler = signal.signal(
                signal.SIGINT,
                lambda sig, frame: ioloop.add_callback_from_signal(shutdown))
            try:
                yield
            finally:
                signal.signal(signal.SIGINT, old_handler)

        # Set the flag to True *before* blocking on ioloop.start()
        cls.started = True

        print("Press Ctrl+C to stop WebAgg server")
        sys.stdout.flush()
        with catch_sigint():
            ioloop.start()
Example #3
Source File: backend_webagg.py    From python3_ios with BSD 3-Clause "New" or "Revised" License 5 votes vote down vote up 
def start(cls):
        if cls.started:
            return

        """
        IOLoop.running() was removed as of Tornado 2.4; see for example
        https://groups.google.com/forum/#!topic/python-tornado/QLMzkpQBGOY
        Thus there is no correct way to check if the loop has already been
        launched. We may end up with two concurrently running loops in that
        unlucky case with all the expected consequences.
        """
        ioloop = tornado.ioloop.IOLoop.instance()

        def shutdown():
            ioloop.stop()
            print("Server is stopped")
            sys.stdout.flush()
            cls.started = False

        @contextmanager
        def catch_sigint():
            old_handler = signal.signal(
                signal.SIGINT,
                lambda sig, frame: ioloop.add_callback_from_signal(shutdown))
            try:
                yield
            finally:
                signal.signal(signal.SIGINT, old_handler)

        # Set the flag to True *before* blocking on ioloop.start()
        cls.started = True

        print("Press Ctrl+C to stop WebAgg server")
        sys.stdout.flush()
        with catch_sigint():
            ioloop.start()
Example #4
Source File: backend_webagg.py    From coffeegrindsize with MIT License 5 votes vote down vote up 
def start(cls):
        if cls.started:
            return

        """
        IOLoop.running() was removed as of Tornado 2.4; see for example
        https://groups.google.com/forum/#!topic/python-tornado/QLMzkpQBGOY
        Thus there is no correct way to check if the loop has already been
        launched. We may end up with two concurrently running loops in that
        unlucky case with all the expected consequences.
        """
        ioloop = tornado.ioloop.IOLoop.instance()

        def shutdown():
            ioloop.stop()
            print("Server is stopped")
            sys.stdout.flush()
            cls.started = False

        @contextmanager
        def catch_sigint():
            old_handler = signal.signal(
                signal.SIGINT,
                lambda sig, frame: ioloop.add_callback_from_signal(shutdown))
            try:
                yield
            finally:
                signal.signal(signal.SIGINT, old_handler)

        # Set the flag to True *before* blocking on ioloop.start()
        cls.started = True

        print("Press Ctrl+C to stop WebAgg server")
        sys.stdout.flush()
        with catch_sigint():
            ioloop.start()
Example #5
Source File: backend_webagg.py    From CogAlg with MIT License 5 votes vote down vote up 
def start(cls):
        if cls.started:
            return

        """
        IOLoop.running() was removed as of Tornado 2.4; see for example
        https://groups.google.com/forum/#!topic/python-tornado/QLMzkpQBGOY
        Thus there is no correct way to check if the loop has already been
        launched. We may end up with two concurrently running loops in that
        unlucky case with all the expected consequences.
        """
        ioloop = tornado.ioloop.IOLoop.instance()

        def shutdown():
            ioloop.stop()
            print("Server is stopped")
            sys.stdout.flush()
            cls.started = False

        @contextmanager
        def catch_sigint():
            old_handler = signal.signal(
                signal.SIGINT,
                lambda sig, frame: ioloop.add_callback_from_signal(shutdown))
            try:
                yield
            finally:
                signal.signal(signal.SIGINT, old_handler)

        # Set the flag to True *before* blocking on ioloop.start()
        cls.started = True

        print("Press Ctrl+C to stop WebAgg server")
        sys.stdout.flush()
        with catch_sigint():
            ioloop.start()
Example #6
Source File: backend_webagg.py    From twitter-stock-recommendation with MIT License 5 votes vote down vote up 
def start(cls):
        if cls.started:
            return

        """
        IOLoop.running() was removed as of Tornado 2.4; see for example
        https://groups.google.com/forum/#!topic/python-tornado/QLMzkpQBGOY
        Thus there is no correct way to check if the loop has already been
        launched. We may end up with two concurrently running loops in that
        unlucky case with all the expected consequences.
        """
        ioloop = tornado.ioloop.IOLoop.instance()

        def shutdown():
            ioloop.stop()
            print("Server is stopped")
            sys.stdout.flush()
            cls.started = False

        @contextmanager
        def catch_sigint():
            old_handler = signal.signal(
                signal.SIGINT,
                lambda sig, frame: ioloop.add_callback_from_signal(shutdown))
            try:
                yield
            finally:
                signal.signal(signal.SIGINT, old_handler)

        # Set the flag to True *before* blocking on ioloop.start()
        cls.started = True

        print("Press Ctrl+C to stop WebAgg server")
        sys.stdout.flush()
        with catch_sigint():
            ioloop.start()