Esempio n. 1
0
class WorkerTest(unittest.TestCase):
    def setUp(self):
        # InstanceCache.disable()
        self.sch = CentralPlannerScheduler(retry_delay=100,
                                           remove_delay=1000,
                                           worker_disconnect_delay=10)
        self.w = Worker(scheduler=self.sch, worker_id='X')
        self.w2 = Worker(scheduler=self.sch, worker_id='Y')
        self.time = time.time

    def tearDown(self):
        if time.time != self.time:
            time.time = self.time
        self.w.stop()
        self.w2.stop()

    def setTime(self, t):
        time.time = lambda: t

    def test_dep(self):
        class A(Task):
            def run(self):
                self.has_run = True

            def complete(self):
                return self.has_run

        a = A()

        class B(Task):
            def requires(self):
                return a

            def run(self):
                self.has_run = True

            def complete(self):
                return self.has_run

        b = B()
        a.has_run = False
        b.has_run = False

        self.assertTrue(self.w.add(b))
        self.assertTrue(self.w.run())
        self.assertTrue(a.has_run)
        self.assertTrue(b.has_run)

    def test_stop_getting_new_work(self):
        d = DummyTask()
        self.w.add(d)

        self.assertFalse(d.complete())
        self.w.handle_interrupt(signal.SIGUSR1, None)
        self.w.run()
        self.assertFalse(d.complete())

    def test_external_dep(self):
        class A(ExternalTask):
            def complete(self):
                return False

        a = A()

        class B(Task):
            def requires(self):
                return a

            def run(self):
                self.has_run = True

            def complete(self):
                return self.has_run

        b = B()

        a.has_run = False
        b.has_run = False

        self.assertTrue(self.w.add(b))
        self.assertTrue(self.w.run())

        self.assertFalse(a.has_run)
        self.assertFalse(b.has_run)

    def test_tracking_url(self):
        tracking_url = 'http://test_url.com/'

        class A(Task):
            has_run = False

            def complete(self):
                return self.has_run

            def run(self, tracking_url_callback=None):
                if tracking_url_callback is not None:
                    tracking_url_callback(tracking_url)
                self.has_run = True

        a = A()
        self.assertTrue(self.w.add(a))
        self.assertTrue(self.w.run())
        tasks = self.sch.task_list('DONE', '')
        self.assertEqual(1, len(tasks))
        self.assertEqual(tracking_url, tasks['A()']['tracking_url'])

    def test_type_error_in_tracking_run(self):
        class A(Task):
            num_runs = 0

            def complete(self):
                return False

            def run(self, tracking_url_callback=None):
                self.num_runs += 1
                raise TypeError('bad type')

        a = A()
        self.assertTrue(self.w.add(a))
        self.assertFalse(self.w.run())

        # Should only run and fail once, not retry because of the type error
        self.assertEqual(1, a.num_runs)

    def test_fail(self):
        class CustomException(BaseException):
            def __init__(self, msg):
                self.msg = msg

        class A(Task):
            def run(self):
                self.has_run = True
                raise CustomException('bad things')

            def complete(self):
                return self.has_run

        a = A()

        class B(Task):
            def requires(self):
                return a

            def run(self):
                self.has_run = True

            def complete(self):
                return self.has_run

        b = B()

        a.has_run = False
        b.has_run = False

        self.assertTrue(self.w.add(b))
        self.assertFalse(self.w.run())

        self.assertTrue(a.has_run)
        self.assertFalse(b.has_run)

    def test_unknown_dep(self):
        # see central_planner_test.CentralPlannerTest.test_remove_dep
        class A(ExternalTask):
            def complete(self):
                return False

        class C(Task):
            def complete(self):
                return True

        def get_b(dep):
            class B(Task):
                def requires(self):
                    return dep

                def run(self):
                    self.has_run = True

                def complete(self):
                    return False

            b = B()
            b.has_run = False
            return b

        b_a = get_b(A())
        b_c = get_b(C())

        self.assertTrue(self.w.add(b_a))
        # So now another worker goes in and schedules C -> B
        # This should remove the dep A -> B but will screw up the first worker
        self.assertTrue(self.w2.add(b_c))

        self.assertFalse(
            self.w.run()
        )  # should not run anything - the worker should detect that A is broken
        self.assertFalse(b_a.has_run)
        # not sure what should happen??
        # self.w2.run() # should run B since C is fulfilled
        # self.assertTrue(b_c.has_run)

    def test_unfulfilled_dep(self):
        class A(Task):
            def complete(self):
                return self.done

            def run(self):
                self.done = True

        def get_b(a):
            class B(A):
                def requires(self):
                    return a

            b = B()
            b.done = False
            a.done = True
            return b

        a = A()
        b = get_b(a)

        self.assertTrue(self.w.add(b))
        a.done = False
        self.w.run()
        self.assertTrue(a.complete())
        self.assertTrue(b.complete())

    def test_avoid_infinite_reschedule(self):
        class A(Task):
            def complete(self):
                return False

        class B(Task):
            def complete(self):
                return False

            def requires(self):
                return A()

        self.assertTrue(self.w.add(B()))
        self.assertFalse(self.w.run())

    def test_allow_reschedule_with_many_missing_deps(self):
        class A(Task):
            """ Task that must run twice to succeed """
            i = luigi.IntParameter()

            runs = 0

            def complete(self):
                return self.runs >= 2

            def run(self):
                self.runs += 1

        class B(Task):
            done = False

            def requires(self):
                return map(A, range(20))

            def complete(self):
                return self.done

            def run(self):
                self.done = True

        b = B()
        w = Worker(scheduler=self.sch, worker_id='X', max_reschedules=1)
        self.assertTrue(w.add(b))
        self.assertFalse(w.run())

        # For b to be done, we must have rescheduled its dependencies to run them twice
        self.assertTrue(b.complete())
        self.assertTrue(all(a.complete() for a in b.deps()))

    def test_interleaved_workers(self):
        class A(DummyTask):
            pass

        a = A()

        class B(DummyTask):
            def requires(self):
                return a

        class ExternalB(ExternalTask):
            task_family = "B"

            def complete(self):
                return False

        b = B()
        eb = ExternalB()
        self.assertEqual(eb.task_id, "B()")

        sch = CentralPlannerScheduler(retry_delay=100,
                                      remove_delay=1000,
                                      worker_disconnect_delay=10)
        w = Worker(scheduler=sch, worker_id='X')
        w2 = Worker(scheduler=sch, worker_id='Y')

        self.assertTrue(w.add(b))
        self.assertTrue(w2.add(eb))
        logging.debug("RUNNING BROKEN WORKER")
        self.assertTrue(w2.run())
        self.assertFalse(a.complete())
        self.assertFalse(b.complete())
        logging.debug("RUNNING FUNCTIONAL WORKER")
        self.assertTrue(w.run())
        self.assertTrue(a.complete())
        self.assertTrue(b.complete())
        w.stop()
        w2.stop()

    def test_interleaved_workers2(self):
        # two tasks without dependencies, one external, one not
        class B(DummyTask):
            pass

        class ExternalB(ExternalTask):
            task_family = "B"

            def complete(self):
                return False

        b = B()
        eb = ExternalB()

        self.assertEqual(eb.task_id, "B()")

        sch = CentralPlannerScheduler(retry_delay=100,
                                      remove_delay=1000,
                                      worker_disconnect_delay=10)
        w = Worker(scheduler=sch, worker_id='X')
        w2 = Worker(scheduler=sch, worker_id='Y')

        self.assertTrue(w2.add(eb))
        self.assertTrue(w.add(b))

        self.assertTrue(w2.run())
        self.assertFalse(b.complete())
        self.assertTrue(w.run())
        self.assertTrue(b.complete())
        w.stop()
        w2.stop()

    def test_interleaved_workers3(self):
        class A(DummyTask):
            def run(self):
                logging.debug('running A')
                time.sleep(0.1)
                super(A, self).run()

        a = A()

        class B(DummyTask):
            def requires(self):
                return a

            def run(self):
                logging.debug('running B')
                super(B, self).run()

        b = B()

        sch = CentralPlannerScheduler(retry_delay=100,
                                      remove_delay=1000,
                                      worker_disconnect_delay=10)

        w = Worker(scheduler=sch,
                   worker_id='X',
                   keep_alive=True,
                   count_uniques=True)
        w2 = Worker(scheduler=sch,
                    worker_id='Y',
                    keep_alive=True,
                    count_uniques=True,
                    wait_interval=0.1)

        self.assertTrue(w.add(a))
        self.assertTrue(w2.add(b))

        threading.Thread(target=w.run).start()
        self.assertTrue(w2.run())

        self.assertTrue(a.complete())
        self.assertTrue(b.complete())

        w.stop()
        w2.stop()

    def test_die_for_non_unique_pending(self):
        class A(DummyTask):
            def run(self):
                logging.debug('running A')
                time.sleep(0.1)
                super(A, self).run()

        a = A()

        class B(DummyTask):
            def requires(self):
                return a

            def run(self):
                logging.debug('running B')
                super(B, self).run()

        b = B()

        sch = CentralPlannerScheduler(retry_delay=100,
                                      remove_delay=1000,
                                      worker_disconnect_delay=10)

        w = Worker(scheduler=sch,
                   worker_id='X',
                   keep_alive=True,
                   count_uniques=True)
        w2 = Worker(scheduler=sch,
                    worker_id='Y',
                    keep_alive=True,
                    count_uniques=True,
                    wait_interval=0.1)

        self.assertTrue(w.add(b))
        self.assertTrue(w2.add(b))

        self.assertEqual(w._get_work()[0], 'A()')
        self.assertTrue(w2.run())

        self.assertFalse(a.complete())
        self.assertFalse(b.complete())

        w2.stop()

    def test_complete_exception(self):
        "Tests that a task is still scheduled if its sister task crashes in the complete() method"

        class A(DummyTask):
            def complete(self):
                raise Exception("doh")

        a = A()

        class C(DummyTask):
            pass

        c = C()

        class B(DummyTask):
            def requires(self):
                return a, c

        b = B()
        sch = CentralPlannerScheduler(retry_delay=100,
                                      remove_delay=1000,
                                      worker_disconnect_delay=10)
        w = Worker(scheduler=sch, worker_id="foo")
        self.assertFalse(w.add(b))
        self.assertTrue(w.run())
        self.assertFalse(b.has_run)
        self.assertTrue(c.has_run)
        self.assertFalse(a.has_run)
        w.stop()

    def test_requires_exception(self):
        class A(DummyTask):
            def requires(self):
                raise Exception("doh")

        a = A()

        class C(DummyTask):
            pass

        c = C()

        class B(DummyTask):
            def requires(self):
                return a, c

        b = B()
        sch = CentralPlannerScheduler(retry_delay=100,
                                      remove_delay=1000,
                                      worker_disconnect_delay=10)
        w = Worker(scheduler=sch, worker_id="foo")
        self.assertFalse(w.add(b))
        self.assertTrue(w.run())
        self.assertFalse(b.has_run)
        self.assertTrue(c.has_run)
        self.assertFalse(a.has_run)
        w.stop()
Esempio n. 2
0
class WorkerTest(unittest.TestCase):

    def setUp(self):
        # InstanceCache.disable()
        self.sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)
        self.w = Worker(scheduler=self.sch, worker_id='X')
        self.w2 = Worker(scheduler=self.sch, worker_id='Y')
        self.time = time.time

    def tearDown(self):
        if time.time != self.time:
            time.time = self.time
        self.w.stop()
        self.w2.stop()

    def setTime(self, t):
        time.time = lambda: t

    def test_dep(self):
        class A(Task):

            def run(self):
                self.has_run = True

            def complete(self):
                return self.has_run
        a = A()

        class B(Task):

            def requires(self):
                return a

            def run(self):
                self.has_run = True

            def complete(self):
                return self.has_run

        b = B()
        a.has_run = False
        b.has_run = False

        self.assertTrue(self.w.add(b))
        self.assertTrue(self.w.run())
        self.assertTrue(a.has_run)
        self.assertTrue(b.has_run)

    def test_stop_getting_new_work(self):
        d = DummyTask()
        self.w.add(d)

        self.assertFalse(d.complete())
        self.w.handle_interrupt(signal.SIGUSR1, None)
        self.w.run()
        self.assertFalse(d.complete())

    def test_external_dep(self):
        class A(ExternalTask):

            def complete(self):
                return False
        a = A()

        class B(Task):

            def requires(self):
                return a

            def run(self):
                self.has_run = True

            def complete(self):
                return self.has_run

        b = B()

        a.has_run = False
        b.has_run = False

        self.assertTrue(self.w.add(b))
        self.assertTrue(self.w.run())

        self.assertFalse(a.has_run)
        self.assertFalse(b.has_run)

    def test_fail(self):
        class A(Task):

            def run(self):
                self.has_run = True
                raise Exception()

            def complete(self):
                return self.has_run

        a = A()

        class B(Task):

            def requires(self):
                return a

            def run(self):
                self.has_run = True

            def complete(self):
                return self.has_run

        b = B()

        a.has_run = False
        b.has_run = False

        self.assertTrue(self.w.add(b))
        self.assertFalse(self.w.run())

        self.assertTrue(a.has_run)
        self.assertFalse(b.has_run)

    def test_unknown_dep(self):
        # see central_planner_test.CentralPlannerTest.test_remove_dep
        class A(ExternalTask):

            def complete(self):
                return False

        class C(Task):

            def complete(self):
                return True

        def get_b(dep):
            class B(Task):

                def requires(self):
                    return dep

                def run(self):
                    self.has_run = True

                def complete(self):
                    return False

            b = B()
            b.has_run = False
            return b

        b_a = get_b(A())
        b_c = get_b(C())

        self.assertTrue(self.w.add(b_a))
        # So now another worker goes in and schedules C -> B
        # This should remove the dep A -> B but will screw up the first worker
        self.assertTrue(self.w2.add(b_c))

        self.assertFalse(self.w.run())  # should not run anything - the worker should detect that A is broken
        self.assertFalse(b_a.has_run)
        # not sure what should happen??
        # self.w2.run() # should run B since C is fulfilled
        # self.assertTrue(b_c.has_run)

    def test_unfulfilled_dep(self):
        class A(Task):

            def complete(self):
                return self.done

            def run(self):
                self.done = True

        def get_b(a):
            class B(A):

                def requires(self):
                    return a
            b = B()
            b.done = False
            a.done = True
            return b

        a = A()
        b = get_b(a)

        self.assertTrue(self.w.add(b))
        a.done = False
        self.w.run()
        self.assertTrue(a.complete())
        self.assertTrue(b.complete())

    def test_avoid_infinite_reschedule(self):
        class A(Task):

            def complete(self):
                return False

        class B(Task):

            def complete(self):
                return False

            def requires(self):
                return A()

        self.assertTrue(self.w.add(B()))
        self.assertFalse(self.w.run())

    def test_allow_reschedule_with_many_missing_deps(self):
        class A(Task):

            """ Task that must run twice to succeed """
            i = luigi.IntParameter()

            runs = 0

            def complete(self):
                return self.runs >= 2

            def run(self):
                self.runs += 1

        class B(Task):
            done = False

            def requires(self):
                return map(A, range(20))

            def complete(self):
                return self.done

            def run(self):
                self.done = True

        b = B()
        w = Worker(scheduler=self.sch, worker_id='X', max_reschedules=1)
        self.assertTrue(w.add(b))
        self.assertFalse(w.run())

        # For b to be done, we must have rescheduled its dependencies to run them twice
        self.assertTrue(b.complete())
        self.assertTrue(all(a.complete() for a in b.deps()))

    def test_interleaved_workers(self):
        class A(DummyTask):
            pass

        a = A()

        class B(DummyTask):

            def requires(self):
                return a

        class ExternalB(ExternalTask):
            task_family = "B"

            def complete(self):
                return False

        b = B()
        eb = ExternalB()
        self.assertEqual(eb.task_id, "B()")

        sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)
        w = Worker(scheduler=sch, worker_id='X')
        w2 = Worker(scheduler=sch, worker_id='Y')

        self.assertTrue(w.add(b))
        self.assertTrue(w2.add(eb))
        logging.debug("RUNNING BROKEN WORKER")
        self.assertTrue(w2.run())
        self.assertFalse(a.complete())
        self.assertFalse(b.complete())
        logging.debug("RUNNING FUNCTIONAL WORKER")
        self.assertTrue(w.run())
        self.assertTrue(a.complete())
        self.assertTrue(b.complete())
        w.stop()
        w2.stop()

    def test_interleaved_workers2(self):
        # two tasks without dependencies, one external, one not
        class B(DummyTask):
            pass

        class ExternalB(ExternalTask):
            task_family = "B"

            def complete(self):
                return False

        b = B()
        eb = ExternalB()

        self.assertEqual(eb.task_id, "B()")

        sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)
        w = Worker(scheduler=sch, worker_id='X')
        w2 = Worker(scheduler=sch, worker_id='Y')

        self.assertTrue(w2.add(eb))
        self.assertTrue(w.add(b))

        self.assertTrue(w2.run())
        self.assertFalse(b.complete())
        self.assertTrue(w.run())
        self.assertTrue(b.complete())
        w.stop()
        w2.stop()

    def test_interleaved_workers3(self):
        class A(DummyTask):

            def run(self):
                logging.debug('running A')
                time.sleep(0.1)
                super(A, self).run()

        a = A()

        class B(DummyTask):

            def requires(self):
                return a

            def run(self):
                logging.debug('running B')
                super(B, self).run()

        b = B()

        sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)

        w = Worker(scheduler=sch, worker_id='X', keep_alive=True, count_uniques=True)
        w2 = Worker(scheduler=sch, worker_id='Y', keep_alive=True, count_uniques=True, wait_interval=0.1)

        self.assertTrue(w.add(a))
        self.assertTrue(w2.add(b))

        threading.Thread(target=w.run).start()
        self.assertTrue(w2.run())

        self.assertTrue(a.complete())
        self.assertTrue(b.complete())

        w.stop()
        w2.stop()

    def test_die_for_non_unique_pending(self):
        class A(DummyTask):

            def run(self):
                logging.debug('running A')
                time.sleep(0.1)
                super(A, self).run()

        a = A()

        class B(DummyTask):

            def requires(self):
                return a

            def run(self):
                logging.debug('running B')
                super(B, self).run()

        b = B()

        sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)

        w = Worker(scheduler=sch, worker_id='X', keep_alive=True, count_uniques=True)
        w2 = Worker(scheduler=sch, worker_id='Y', keep_alive=True, count_uniques=True, wait_interval=0.1)

        self.assertTrue(w.add(b))
        self.assertTrue(w2.add(b))

        self.assertEqual(w._get_work()[0], 'A()')
        self.assertTrue(w2.run())

        self.assertFalse(a.complete())
        self.assertFalse(b.complete())

        w2.stop()

    def test_complete_exception(self):
        "Tests that a task is still scheduled if its sister task crashes in the complete() method"
        class A(DummyTask):

            def complete(self):
                raise Exception("doh")

        a = A()

        class C(DummyTask):
            pass

        c = C()

        class B(DummyTask):

            def requires(self):
                return a, c

        b = B()
        sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)
        w = Worker(scheduler=sch, worker_id="foo")
        self.assertFalse(w.add(b))
        self.assertTrue(w.run())
        self.assertFalse(b.has_run)
        self.assertTrue(c.has_run)
        self.assertFalse(a.has_run)
        w.stop()

    def test_requires_exception(self):
        class A(DummyTask):

            def requires(self):
                raise Exception("doh")

        a = A()

        class C(DummyTask):
            pass

        c = C()

        class B(DummyTask):

            def requires(self):
                return a, c

        b = B()
        sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)
        w = Worker(scheduler=sch, worker_id="foo")
        self.assertFalse(w.add(b))
        self.assertTrue(w.run())
        self.assertFalse(b.has_run)
        self.assertTrue(c.has_run)
        self.assertFalse(a.has_run)
        w.stop()
Esempio n. 3
0
class WorkerTest(unittest.TestCase):

    def setUp(self):
        # InstanceCache.disable()
        self.sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)
        self.w = Worker(scheduler=self.sch, worker_id='X')
        self.w2 = Worker(scheduler=self.sch, worker_id='Y')
        self.time = time.time

    def tearDown(self):
        if time.time != self.time:
            time.time = self.time
        self.w.stop()
        self.w2.stop()

    def setTime(self, t):
        time.time = lambda: t

    def test_dep(self):
        class A(Task):

            def run(self):
                self.has_run = True

            def complete(self):
                return self.has_run
        a = A()

        class B(Task):

            def requires(self):
                return a

            def run(self):
                self.has_run = True

            def complete(self):
                return self.has_run

        b = B()
        a.has_run = False
        b.has_run = False

        self.assertTrue(self.w.add(b))
        self.assertTrue(self.w.run())
        self.assertTrue(a.has_run)
        self.assertTrue(b.has_run)

    def test_stop_getting_new_work(self):
        d = DummyTask()
        self.w.add(d)

        self.assertFalse(d.complete())
        try:
            self.w.handle_interrupt(signal.SIGUSR1, None)
        except AttributeError:
            raise unittest.SkipTest('signal.SIGUSR1 not found on this system')
        self.w.run()
        self.assertFalse(d.complete())

    def test_external_dep(self):
        class A(ExternalTask):

            def complete(self):
                return False
        a = A()

        class B(Task):

            def requires(self):
                return a

            def run(self):
                self.has_run = True

            def complete(self):
                return self.has_run

        b = B()

        a.has_run = False
        b.has_run = False

        self.assertTrue(self.w.add(b))
        self.assertTrue(self.w.run())

        self.assertFalse(a.has_run)
        self.assertFalse(b.has_run)

    def test_tracking_url(self):
        tracking_url = 'http://test_url.com/'

        class A(Task):
            has_run = False

            def complete(self):
                return self.has_run

            def run(self, tracking_url_callback=None):
                if tracking_url_callback is not None:
                    tracking_url_callback(tracking_url)
                self.has_run = True

        a = A()
        self.assertTrue(self.w.add(a))
        self.assertTrue(self.w.run())
        tasks = self.sch.task_list('DONE', '')
        self.assertEqual(1, len(tasks))
        self.assertEqual(tracking_url, tasks['A()']['tracking_url'])

    def test_type_error_in_tracking_run(self):
        class A(Task):
            num_runs = 0

            def complete(self):
                return False

            def run(self, tracking_url_callback=None):
                self.num_runs += 1
                raise TypeError('bad type')

        a = A()
        self.assertTrue(self.w.add(a))
        self.assertFalse(self.w.run())

        # Should only run and fail once, not retry because of the type error
        self.assertEqual(1, a.num_runs)

    def test_fail(self):
        class CustomException(BaseException):
            def __init__(self, msg):
                self.msg = msg

        class A(Task):

            def run(self):
                self.has_run = True
                raise CustomException('bad things')

            def complete(self):
                return self.has_run

        a = A()

        class B(Task):

            def requires(self):
                return a

            def run(self):
                self.has_run = True

            def complete(self):
                return self.has_run

        b = B()

        a.has_run = False
        b.has_run = False

        self.assertTrue(self.w.add(b))
        self.assertFalse(self.w.run())

        self.assertTrue(a.has_run)
        self.assertFalse(b.has_run)

    def test_unknown_dep(self):
        # see central_planner_test.CentralPlannerTest.test_remove_dep
        class A(ExternalTask):

            def complete(self):
                return False

        class C(Task):

            def complete(self):
                return True

        def get_b(dep):
            class B(Task):

                def requires(self):
                    return dep

                def run(self):
                    self.has_run = True

                def complete(self):
                    return False

            b = B()
            b.has_run = False
            return b

        b_a = get_b(A())
        b_c = get_b(C())

        self.assertTrue(self.w.add(b_a))
        # So now another worker goes in and schedules C -> B
        # This should remove the dep A -> B but will screw up the first worker
        self.assertTrue(self.w2.add(b_c))

        self.assertFalse(self.w.run())  # should not run anything - the worker should detect that A is broken
        self.assertFalse(b_a.has_run)
        # not sure what should happen??
        # self.w2.run() # should run B since C is fulfilled
        # self.assertTrue(b_c.has_run)

    def test_unfulfilled_dep(self):
        class A(Task):

            def complete(self):
                return self.done

            def run(self):
                self.done = True

        def get_b(a):
            class B(A):

                def requires(self):
                    return a
            b = B()
            b.done = False
            a.done = True
            return b

        a = A()
        b = get_b(a)

        self.assertTrue(self.w.add(b))
        a.done = False
        self.w.run()
        self.assertTrue(a.complete())
        self.assertTrue(b.complete())

    def test_gets_missed_work(self):
        class A(Task):
            done = False

            def complete(self):
                return self.done

            def run(self):
                self.done = True

        a = A()
        self.assertTrue(self.w.add(a))

        # simulate a missed get_work response
        self.assertEqual('A()', self.sch.get_work(worker='X')['task_id'])

        self.assertTrue(self.w.run())
        self.assertTrue(a.complete())

    def test_avoid_infinite_reschedule(self):
        class A(Task):

            def complete(self):
                return False

        class B(Task):

            def complete(self):
                return False

            def requires(self):
                return A()

        self.assertTrue(self.w.add(B()))
        self.assertFalse(self.w.run())

    def test_fails_registering_signal(self):
        with mock.patch('luigi.worker.signal', spec=['signal']):
            # mock will raise an attribute error getting signal.SIGUSR1
            Worker()

    def test_allow_reschedule_with_many_missing_deps(self):
        class A(Task):

            """ Task that must run twice to succeed """
            i = luigi.IntParameter()

            runs = 0

            def complete(self):
                return self.runs >= 2

            def run(self):
                self.runs += 1

        class B(Task):
            done = False

            def requires(self):
                return map(A, range(20))

            def complete(self):
                return self.done

            def run(self):
                self.done = True

        b = B()
        w = Worker(scheduler=self.sch, worker_id='X', max_reschedules=1)
        self.assertTrue(w.add(b))
        self.assertFalse(w.run())

        # For b to be done, we must have rescheduled its dependencies to run them twice
        self.assertTrue(b.complete())
        self.assertTrue(all(a.complete() for a in b.deps()))

    def test_interleaved_workers(self):
        class A(DummyTask):
            pass

        a = A()

        class B(DummyTask):

            def requires(self):
                return a

        class ExternalB(ExternalTask):
            task_family = "B"

            def complete(self):
                return False

        b = B()
        eb = ExternalB()
        self.assertEqual(eb.task_id, "B()")

        sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)
        w = Worker(scheduler=sch, worker_id='X')
        w2 = Worker(scheduler=sch, worker_id='Y')

        self.assertTrue(w.add(b))
        self.assertTrue(w2.add(eb))
        logging.debug("RUNNING BROKEN WORKER")
        self.assertTrue(w2.run())
        self.assertFalse(a.complete())
        self.assertFalse(b.complete())
        logging.debug("RUNNING FUNCTIONAL WORKER")
        self.assertTrue(w.run())
        self.assertTrue(a.complete())
        self.assertTrue(b.complete())
        w.stop()
        w2.stop()

    def test_interleaved_workers2(self):
        # two tasks without dependencies, one external, one not
        class B(DummyTask):
            pass

        class ExternalB(ExternalTask):
            task_family = "B"

            def complete(self):
                return False

        b = B()
        eb = ExternalB()

        self.assertEqual(eb.task_id, "B()")

        sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)
        w = Worker(scheduler=sch, worker_id='X')
        w2 = Worker(scheduler=sch, worker_id='Y')

        self.assertTrue(w2.add(eb))
        self.assertTrue(w.add(b))

        self.assertTrue(w2.run())
        self.assertFalse(b.complete())
        self.assertTrue(w.run())
        self.assertTrue(b.complete())
        w.stop()
        w2.stop()

    def test_interleaved_workers3(self):
        class A(DummyTask):

            def run(self):
                logging.debug('running A')
                time.sleep(0.1)
                super(A, self).run()

        a = A()

        class B(DummyTask):

            def requires(self):
                return a

            def run(self):
                logging.debug('running B')
                super(B, self).run()

        b = B()

        sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)

        w = Worker(scheduler=sch, worker_id='X', keep_alive=True, count_uniques=True)
        w2 = Worker(scheduler=sch, worker_id='Y', keep_alive=True, count_uniques=True, wait_interval=0.1)

        self.assertTrue(w.add(a))
        self.assertTrue(w2.add(b))

        threading.Thread(target=w.run).start()
        self.assertTrue(w2.run())

        self.assertTrue(a.complete())
        self.assertTrue(b.complete())

        w.stop()
        w2.stop()

    def test_die_for_non_unique_pending(self):
        class A(DummyTask):

            def run(self):
                logging.debug('running A')
                time.sleep(0.1)
                super(A, self).run()

        a = A()

        class B(DummyTask):

            def requires(self):
                return a

            def run(self):
                logging.debug('running B')
                super(B, self).run()

        b = B()

        sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)

        w = Worker(scheduler=sch, worker_id='X', keep_alive=True, count_uniques=True)
        w2 = Worker(scheduler=sch, worker_id='Y', keep_alive=True, count_uniques=True, wait_interval=0.1)

        self.assertTrue(w.add(b))
        self.assertTrue(w2.add(b))

        self.assertEqual(w._get_work()[0], 'A()')
        self.assertTrue(w2.run())

        self.assertFalse(a.complete())
        self.assertFalse(b.complete())

        w2.stop()

    def test_complete_exception(self):
        "Tests that a task is still scheduled if its sister task crashes in the complete() method"
        class A(DummyTask):

            def complete(self):
                raise Exception("doh")

        a = A()

        class C(DummyTask):
            pass

        c = C()

        class B(DummyTask):

            def requires(self):
                return a, c

        b = B()
        sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)
        w = Worker(scheduler=sch, worker_id="foo")
        self.assertFalse(w.add(b))
        self.assertTrue(w.run())
        self.assertFalse(b.has_run)
        self.assertTrue(c.has_run)
        self.assertFalse(a.has_run)
        w.stop()

    def test_requires_exception(self):
        class A(DummyTask):

            def requires(self):
                raise Exception("doh")

        a = A()

        class D(DummyTask):
            pass

        d = D()

        class C(DummyTask):
            def requires(self):
                return d

        c = C()

        class B(DummyTask):

            def requires(self):
                return c, a

        b = B()
        sch = CentralPlannerScheduler(retry_delay=100, remove_delay=1000, worker_disconnect_delay=10)
        w = Worker(scheduler=sch, worker_id="foo")
        self.assertFalse(w.add(b))
        self.assertTrue(w.run())
        self.assertFalse(b.has_run)
        self.assertTrue(c.has_run)
        self.assertTrue(d.has_run)
        self.assertFalse(a.has_run)
        w.stop()