def __init__(self):
        from twisted.internet import reactor  # Imported here.inside

        self.reactor = reactor

        engine = get_engine()
        # create_schema(engine)

        self.read_pool = ThreadPool(
            minthreads=1, maxthreads=16, name="ReadPool")

        self.write_pool = ThreadPool(
            minthreads=1, maxthreads=1, name="WritePool")

        self.read_pool.start()
        self.write_pool.start()

        self.signals = SignalManager(dispatcher.Any).connect(
            self.stop_threadpools, spider_closed)

        self.counters = defaultdict(lambda: Counter())

        self.cache = defaultdict(
            lambda: dict())

        self.write_queue = Queue()
        self.writelock = False  # Write queue mutex

    def makeService(self, options):
        app = Application("Mercurial SSH Server") #, uid, gid)
        services = IServiceCollection(app)
        service = options.subOptions.getService()
        service.setServiceParent(services)


        wsgi_app = WSGIApplication()
        threadpool = ThreadPool(config.web.min_threads, config.web.max_threads)
        threadpool.start()
        reactor.addSystemEventTrigger('after', 'shutdown', threadpool.stop)
        root = wsgi.WSGIResource(reactor, threadpool, wsgi_app)
        factory = server.Site(root)
        if isfile(config.web.certificate):
            from OpenSSL import SSL
            # Run SSL Server
            class SSLContext(object):
                def getContext(self):
                    ctx = SSL.Context(SSL.SSLv23_METHOD)
                    ctx.use_privatekey_file(config.private_key)
                    ctx.use_certificate_file(config.web.certificate)
                    return ctx
            config_service = internet.SSLServer(config.web.port, factory,
                                                SSLContext())
        else:
            config_service = internet.TCPServer(config.web.port, factory)
        config_service.setServiceParent(app)

        clean_changes_task = task.LoopingCall(self.__clean_old_changes_from_db)
        clean_changes_task.start(5*60, now=True) # Every 5 minutes
        reactor.addSystemEventTrigger('after', 'shutdown',
                                      clean_changes_task.stop)
        return services

class ClockWithThreads(Clock):
    """
    A testing reactor that supplies L{IReactorTime} and L{IReactorThreads}.
    """

    def __init__(self):
        super(ClockWithThreads, self).__init__()
        self._pool = ThreadPool()


    def getThreadPool(self):
        """
        Get the threadpool.
        """
        return self._pool


    def suggestThreadPoolSize(self, size):
        """
        Approximate the behavior of a 'real' reactor.
        """
        self._pool.adjustPoolsize(maxthreads=size)


    def callInThread(self, thunk, *a, **kw):
        """
        No implementation.
        """


    def callFromThread(self, thunk, *a, **kw):
        """

    def __init__(self):
        minthreads = config["jobtype_logging_threadpool"]["min_threads"]
        maxthreads = config["jobtype_logging_threadpool"]["max_threads"]
        self.max_queued_lines = \
            config["jobtype_logging_threadpool"]["max_queue_size"]
        self.flush_lines = \
            config["jobtype_logging_threadpool"]["flush_lines"]
        self.stopped = False

        if minthreads < 1:
            raise ValueError(
                "Config value "
                "jobtype_logging_threadpool.min_threads must be >= 1")

        # Calculate maxthreads if a value was not provided for us
        if maxthreads == "auto":
            auto_maxthreads = min(int(cpu.total_cpus() * 1.5), 20)
            maxthreads = max(auto_maxthreads, minthreads)

        if minthreads > maxthreads:
            raise ValueError(
                "Config value jobtype_logging_threadpool.min_threads cannot "
                "be larger than jobtype_logging_threadpool.max_threads")

        ThreadPool.__init__(
            self,
            minthreads=minthreads, maxthreads=maxthreads,
            name=self.__class__.__name__)

    def from_config(cls, reactor, logger, queue, config_path):
        with open(config_path) as f:
            config = yaml.safe_load(f)

        # TODO: bump this once alchimia properly handles pinning
        thread_pool = ThreadPool(minthreads=1, maxthreads=1)
        thread_pool.start()
        reactor.addSystemEventTrigger('during', 'shutdown', thread_pool.stop)

        return cls(
            logger,
            DownloadDatabase(reactor, thread_pool, config["db"]["uri"]),
            FilePath(config["storage"]["filesystem"]),
            fernet.MultiFernet([
                fernet.Fernet(key) for key in config["encryption_keys"]
            ]),
            VBMSClient(
                reactor,
                connect_vbms_path=config["connect_vbms"]["path"],
                bundle_path=config["connect_vbms"]["bundle_path"],
                endpoint_url=config["vbms"]["endpoint_url"],
                keyfile=config["vbms"]["keyfile"],
                samlfile=config["vbms"]["samlfile"],
                key=config["vbms"].get("key"),
                keypass=config["vbms"]["keypass"],
                ca_cert=config["vbms"].get("ca_cert"),
                client_cert=config["vbms"].get("client_cert"),
            ),
            queue,
            config["env"],
        )

class FakeReactor(object):
    """
    A fake reactor implementation which just supports enough reactor APIs for
    L{ThreadedResolver}.
    """
    implements(IReactorTime, IReactorThreads)

    def __init__(self):
        self._clock = Clock()
        self.callLater = self._clock.callLater

        self._threadpool = ThreadPool()
        self._threadpool.start()
        self.getThreadPool = lambda: self._threadpool

        self._threadCalls = Queue()


    def callFromThread(self, f, *args, **kwargs):
        self._threadCalls.put((f, args, kwargs))


    def _runThreadCalls(self):
        f, args, kwargs = self._threadCalls.get()
        f(*args, **kwargs)


    def _stop(self):
        self._threadpool.stop()

 def __init__(self, core):
     thread_pool = ThreadPool()
     thread_pool.start()
     reactor.addSystemEventTrigger("after", "shutdown", thread_pool.stop)
     application = get_flask_application(core)
     wsgi_resource = WSGIResource(reactor, thread_pool, application)
     Site.__init__(self, wsgi_resource)

class NoGoStatusCodes(TestCase):

    def __init__(self, *args, **kwargs):
        self.tp = ThreadPool(maxthreads=20)
        self.tp.start()

        self.resource = HendrixWSGIResource(reactor,
                                            self.tp,
                                            self.wsgi_thing)

        self.nameSpace = TestNameSpace()
        self.nameSpace.async_thing_complete = Queue()
        return super(NoGoStatusCodes, self).__init__(*args, **kwargs)

    def setUp(self, *args, **kwargs):
        self.addCleanup(self.tp.stop)
        super(NoGoStatusCodes, self).setUp(*args, **kwargs)

    def wsgi_thing(self, environ, start_response):
            start_response('404 NOT FOUND', [('Content-type','text/plain')])

            @crosstown_traffic.follow_response(
                no_go_status_codes=self.no_go_status_codes,
                same_thread=True
            )
            def long_thing_on_same_thread():
                self.nameSpace.async_task_was_run = True
                logger.info("No bad status codes; went ahead with async thing.")

            return "Nothing."

    def test_bad_status_codes_cause_no_go_in_wsgi_response(self):
        self.no_go_status_codes = [404, '6xx']

        request = DummyRequest('r1')
        request.isSecure = lambda: False
        request.content = "llamas"

        finished = request.notifyFinish()

        self.resource.render(request)

        # This must wait until the WSGI response is closed.
        finished.addCallback(
            lambda _: self.assertFalse(
                self.nameSpace.async_task_was_run
            )
        )

    def test_bad_status_codes_cause_no_go_flag(self):
        through_to_you = crosstown_traffic.follow_response(no_go_status_codes=[418])
        through_to_you.status_code = 418
        through_to_you.check_status_code_against_no_go_list()
        self.assertTrue(through_to_you.no_go)

    def test_no_bad_status_codes_are_cool(self):
        through_to_you = crosstown_traffic.follow_response(no_go_status_codes=[418])
        through_to_you.status_code = 404
        through_to_you.check_status_code_against_no_go_list()
        self.assertFalse(through_to_you.no_go)

    def test_contemporaneous_requests(self):

        '''
        We're going to create two request-response cycles here:

        Cycle 1 will begin.
        Cycle 2 will begin.
        Cycle 2 will return.
        Cycle 1 will return.

        This way, we can prove that the crosstown_traffic created
        by cycle 1 is not resolved by the return of cycle 2.
        '''
        tp = ThreadPool(maxthreads=20)
        tp.start()
        self.addCleanup(tp.stop)


        log.debug("\n\nStarting the two stream stuff.")

        request1 = DummyRequest('r1')
        request1.isSecure = lambda: False
        request1.content = "Nothing really here."
        request1.headers['llamas'] = 'dingo'

        nameSpace.test_case = self

        hr = HendrixWSGIResource(reactor, tp, wsgi_application)
        d1 = deferToThreadPool(reactor, tp, hr.render, request1)

        request2 = DummyRequest('r2')
        request2.isSecure = lambda: False
        request2.content = "Nothing really here."
        request2.headers['llamas'] = 'dingo'

        d2 = deferToThreadPool(reactor, tp, hr.render, request2)

        def woah_stop(failure):
            nameSpace.async_task_was_done.put_nowait(False)
            nameSpace.second_cycle_complete.put_nowait(False)
            nameSpace.ready_to_proceed_with_second_cycle.put_nowait(False)

        d1.addErrback(woah_stop)
        d2.addErrback(woah_stop)

        combo_deferred = gatherResults([d1, d2])

        def wait_for_queue_resolution():
            nameSpace.async_task_was_done.get(True, 3)

        combo_deferred.addCallback(
            lambda _: deferToThreadPool(reactor, tp, wait_for_queue_resolution)
        )

        combo_deferred.addCallback(
            lambda _: self.assertTrue(nameSpace.async_task_was_run)
        )

        return combo_deferred

    def __init__(self, engine, maxthreads=10, verbose=False):
        if engine.dialect.name == 'sqlite':
            ThreadPool.__init__(self, minthreads=1, maxthreads=1)
        else:
            ThreadPool.__init__(self, maxthreads=maxthreads)

        self.engine = engine
        reactor.callWhenRunning(self.start)

def _test_StreamingServer():
    expected_id = 'test'
    headers = {
        #'TimeSeekRange.dlna.org': 'npt=30.000-',
        'TimeSeekRange.dlna.org': 'npt=20.000-50.000',
        #'Range': 'bytes=5-',
        'Connection': 'close',
    }
    duration = '00:01:00'
    content_length = 64 * 1024
    interface = '192.168.0.103'

    class StreamingServerStub(ByteSeekMixin, TimeSeekMixin, StreamingServer):
        def get_content(self, id, environ):
            eq_(expected_id, id)
            #raise ValueError(repr(environ))
            for k in headers:
                eq_(headers[k], environ['HTTP_' + k.upper()])
            return ContentStub(content_length,
                               'video/mpeg',
                               'DLNA.ORG_PN=MPEG_PS_NTSC;DLNA.ORG_OP=11')

    from twisted.web import client

    class HTTPPageGetter(client.HTTPPageGetter):
        handleStatus_206 = lambda self: self.handleStatus_200()

    class HTTPClientFactory(client.HTTPClientFactory):
        protocol = HTTPPageGetter

    def getPageFactory(url, *args, **kwargs):
        scheme, host, port, path = client._parse(url)
        factory = HTTPClientFactory(url, *args, **kwargs)
        reactor.connectTCP(host, port, factory)
        return factory

    app = StreamingServerStub('test')

    mapper = Mapper()
    mapper.connect(':id', controller='mt', action='get')
    app = RoutesMiddleware(app, mapper)

    tpool = ThreadPool()
    tpool.start()
    resource = upnp.WSGIResource(reactor, tpool, app)
    port = reactor.listenTCP(0, server.Site(resource), interface=interface)

    port_num = port.socket.getsockname()[1]
    url = 'http://%s:%i/%s?duration=%s' % (interface, port_num, expected_id, duration)
    factory = getPageFactory(url, headers=headers)
    def check_result(contents):
        raise ValueError('expected: %d, actual: %d' % (content_length, len(contents)))
        #raise ValueError(repr(factory.response_headers))
        eq_(content_length, len(contents))
    factory.deferred.addCallback(check_result)

    reactor.callLater(5, reactor.stop)
    reactor.run()

 def run(self, handler):
     from twisted.web import server, wsgi
     from twisted.python.threadpool import ThreadPool
     from twisted.internet import reactor
     thread_pool = ThreadPool()
     thread_pool.start()
     reactor.addSystemEventTrigger('after', 'shutdown', thread_pool.stop)
     factory = server.Site(wsgi.WSGIResource(reactor, thread_pool, handler))
     reactor.listenTCP(self.port, factory, interface=self.host)

 def start(self):
     """
     Starts the logger pool and sets up the required shutdown event
     trigger which will call :meth:`stop` on exit.
     """
     reactor.addSystemEventTrigger("before", "shutdown", self.stop)
     ThreadPool.start(self)
     logger.debug(
         "Started logger thread pool (min=%s, max=%s)", self.min, self.max)

    def __init__(self, engine, verbose=False):
        if engine.dialect.name == "sqlite":
            pool_size = 1

            ThreadPool.__init__(self, minthreads=1, maxthreads=1)
        else:
            ThreadPool.__init__(self)

        self.engine = engine
        reactor.callWhenRunning(self.start)

 def twisted(app, address, **options):
     from twisted.web import server, wsgi
     from twisted.python.threadpool import ThreadPool
     from twisted.internet import reactor
     thread_pool = ThreadPool()
     thread_pool.start()
     reactor.addSystemEventTrigger('after', 'shutdown', thread_pool.stop)
     factory = server.Site(wsgi.WSGIResource(reactor, thread_pool, app))
     reactor.listenTCP(address[1], factory, interface=address[0])
     reactor.run()

 def _worker(self):
     self.workerThread = threading.current_thread()
     assert self.session is None
     self.session = self.context.db._createSession()
     try:
         ThreadPool._worker(self)
     finally:
         assert self.session is not None
         self.session.commit()
         self.session.close()

    def __init__(self):
        log.debug("[D] %s %s " % (__file__, __name__), "Starting db_threadpool")
        self.db_threadpool = ThreadPool(0, config.advanced.db_thread_pool_size)
        self.db_threadpool.start()

        log.debug("[D] %s %s " % (__file__, __name__), "Starting scheduler_threadpool")
        self.scheduler_threadpool = ThreadPool(0, config.advanced.scheduler_thread_pool_size)
        self.scheduler_threadpool.start()

        self.transactor = Transactor(self.db_threadpool)
        self.transactor.retries = 0

class ThreadPoolService(Service):
    def __init__(self):
        self.threadpool = ThreadPool()


    def startService(self):
        self.threadpool.start()


    def stopService(self):
        self.threadpool.stop()

class SameOrDifferentThread(TestCase):
    def setUp(self, *args, **kwargs):
        self.tp = ThreadPool()
        self.tp.start()
        self.addCleanup(self.tp.stop)
        super(SameOrDifferentThread, self).setUp(*args, **kwargs)

    def wsgi_thing(self, environ, start_response):
        start_response('200 OK', [('Content-type', 'text/plain')])

        nameSpace.this_thread = threading.current_thread()

        @crosstown_traffic(
            same_thread=self.use_same_thread
        )
        def long_thing_on_same_thread():
            nameSpace.thread_that_is_supposed_to_be_the_same = threading.current_thread()
            log.debug("Finished async thing on same thread.")

        return [b"Nothing."]

    def assert_that_threads_are_the_same(self):
        self.assertEqual(
            nameSpace.this_thread,
            nameSpace.thread_that_is_supposed_to_be_the_same
        )

    def assert_that_threads_are_different(self):
        self.assertNotEqual(nameSpace.this_thread,
                            nameSpace.thread_that_is_supposed_to_be_different)

    def request_same_or_different_thread_thread(self):
        hr = HendrixWSGIResource(reactor, self.tp, self.wsgi_thing)
        request1 = DummyRequest([b'r1'])
        request1.isSecure = lambda: False
        request1.content = b"llamas"
        request1.client = IPv4Address("TCP", b"50.0.50.0", 5000)
        d = deferToThreadPool(reactor, self.tp, hr.render, request1)
        d.addCallback(lambda _: request1.notifyFinish())
        return d

    def test_that_threads_are_the_same(self):
        self.use_same_thread = True
        d = self.request_same_or_different_thread_thread()
        d.addCallback(lambda _: self.assert_that_threads_are_the_same)
        return pytest_twisted.blockon(d)

    def test_that_threads_are_different(self):
        self.use_same_thread = False
        d = self.request_same_or_different_thread_thread()
        d.addCallback(lambda _: self.assert_that_threads_are_different)
        return pytest_twisted.blockon(d)

def twisted_adapter(host, port):
    from twisted.web import server, wsgi
    from twisted.python.threadpool import ThreadPool
    from twisted.internet import reactor

    thread_pool = ThreadPool()
    thread_pool.start()
    reactor.addSystemEventTrigger('after', 'shutdown', thread_pool.stop)

    ittyResource = wsgi.WSGIResource(reactor, thread_pool, handle_request)
    site = server.Site(ittyResource)
    reactor.listenTCP(port, site)
    reactor.run()