ray/test/failure_test.py

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import numpy as np
import os
import ray
import sys
import tempfile
import time
import unittest

import ray.test.test_functions as test_functions

if sys.version_info >= (3, 0):
    from importlib import reload


def relevant_errors(error_type):
    return [info for info in ray.error_info() if info[b"type"] == error_type]


def wait_for_errors(error_type, num_errors, timeout=10):
    start_time = time.time()
    while time.time() - start_time < timeout:
        if len(relevant_errors(error_type)) >= num_errors:
            return
        time.sleep(0.1)
    print("Timing out of wait.")


class TaskStatusTest(unittest.TestCase):
    def testFailedTask(self):
        reload(test_functions)
        ray.init(num_workers=3, driver_mode=ray.SILENT_MODE)

        test_functions.throw_exception_fct1.remote()
        test_functions.throw_exception_fct1.remote()
        wait_for_errors(b"task", 2)
        self.assertEqual(len(relevant_errors(b"task")), 2)
        for task in relevant_errors(b"task"):
            self.assertIn(b"Test function 1 intentionally failed.",
                          task.get(b"message"))

        x = test_functions.throw_exception_fct2.remote()
        try:
            ray.get(x)
        except Exception as e:
            self.assertIn("Test function 2 intentionally failed.", str(e))
        else:
            # ray.get should throw an exception.
            self.assertTrue(False)

        x, y, z = test_functions.throw_exception_fct3.remote(1.0)
        for ref in [x, y, z]:
            try:
                ray.get(ref)
            except Exception as e:
                self.assertIn("Test function 3 intentionally failed.", str(e))
            else:
                # ray.get should throw an exception.
                self.assertTrue(False)

        ray.worker.cleanup()

    def testFailImportingRemoteFunction(self):
        ray.init(num_workers=2, driver_mode=ray.SILENT_MODE)

        # Create the contents of a temporary Python file.
        temporary_python_file = """
def temporary_helper_function():
    return 1
"""

        f = tempfile.NamedTemporaryFile(suffix=".py")
        f.write(temporary_python_file.encode("ascii"))
        f.flush()
        directory = os.path.dirname(f.name)
        # Get the module name and strip ".py" from the end.
        module_name = os.path.basename(f.name)[:-3]
        sys.path.append(directory)
        module = __import__(module_name)

        # Define a function that closes over this temporary module. This should
        # fail when it is unpickled.
        @ray.remote
        def g():
            return module.temporary_python_file()

        wait_for_errors(b"register_remote_function", 2)
        self.assertIn(b"No module named", ray.error_info()[0][b"message"])
        self.assertIn(b"No module named", ray.error_info()[1][b"message"])

        # Check that if we try to call the function it throws an exception and
        # does not hang.
        for _ in range(10):
            self.assertRaises(Exception, lambda: ray.get(g.remote()))

        f.close()

        # Clean up the junk we added to sys.path.
        sys.path.pop(-1)
        ray.worker.cleanup()

    def testFailedFunctionToRun(self):
        ray.init(num_workers=2, driver_mode=ray.SILENT_MODE)

        def f(worker):
            if ray.worker.global_worker.mode == ray.WORKER_MODE:
                raise Exception("Function to run failed.")
        ray.worker.global_worker.run_function_on_all_workers(f)
        wait_for_errors(b"function_to_run", 2)
        # Check that the error message is in the task info.
        self.assertEqual(len(ray.error_info()), 2)
        self.assertIn(b"Function to run failed.",
                      ray.error_info()[0][b"message"])
        self.assertIn(b"Function to run failed.",
                      ray.error_info()[1][b"message"])

        ray.worker.cleanup()

    def testFailImportingActor(self):
        ray.init(num_workers=2, driver_mode=ray.SILENT_MODE)

        # Create the contents of a temporary Python file.
        temporary_python_file = """
def temporary_helper_function():
    return 1
"""

        f = tempfile.NamedTemporaryFile(suffix=".py")
        f.write(temporary_python_file.encode("ascii"))
        f.flush()
        directory = os.path.dirname(f.name)
        # Get the module name and strip ".py" from the end.
        module_name = os.path.basename(f.name)[:-3]
        sys.path.append(directory)
        module = __import__(module_name)

        # Define an actor that closes over this temporary module. This should
        # fail when it is unpickled.
        @ray.remote
        class Foo(object):
            def __init__(self):
                self.x = module.temporary_python_file()

            def get_val(self):
                return 1

        # There should be no errors yet.
        self.assertEqual(len(ray.error_info()), 0)

        # Create an actor.
        foo = Foo.remote()

        # Wait for the error to arrive.
        wait_for_errors(b"register_actor", 1)
        self.assertIn(b"No module named", ray.error_info()[0][b"message"])

        # Wait for the error from when the __init__ tries to run.
        wait_for_errors(b"task", 1)
        self.assertIn(
            b"failed to be imported, and so cannot execute this method",
            ray.error_info()[1][b"message"])

        # Check that if we try to get the function it throws an exception and
        # does not hang.
        with self.assertRaises(Exception):
            ray.get(foo.get_val.remote())

        # Wait for the error from when the call to get_val.
        wait_for_errors(b"task", 2)
        self.assertIn(
            b"failed to be imported, and so cannot execute this method",
            ray.error_info()[2][b"message"])

        f.close()

        # Clean up the junk we added to sys.path.
        sys.path.pop(-1)
        ray.worker.cleanup()


class ActorTest(unittest.TestCase):

    def testFailedActorInit(self):
        ray.init(num_workers=0, driver_mode=ray.SILENT_MODE)

        error_message1 = "actor constructor failed"
        error_message2 = "actor method failed"

        @ray.remote
        class FailedActor(object):
            def __init__(self):
                raise Exception(error_message1)

            def get_val(self):
                return 1

            def fail_method(self):
                raise Exception(error_message2)

        a = FailedActor.remote()

        # Make sure that we get errors from a failed constructor.
        wait_for_errors(b"task", 1)
        self.assertEqual(len(ray.error_info()), 1)
        self.assertIn(error_message1,
                      ray.error_info()[0][b"message"].decode("ascii"))

        # Make sure that we get errors from a failed method.
        a.fail_method.remote()
        wait_for_errors(b"task", 2)
        self.assertEqual(len(ray.error_info()), 2)
        self.assertIn(error_message2,
                      ray.error_info()[1][b"message"].decode("ascii"))

        ray.worker.cleanup()

    def testIncorrectMethodCalls(self):
        ray.init(num_workers=0, driver_mode=ray.SILENT_MODE)

        @ray.remote
        class Actor(object):
            def __init__(self, missing_variable_name):
                pass

            def get_val(self, x):
                pass

        # Make sure that we get errors if we call the constructor incorrectly.

        # Create an actor with too few arguments.
        with self.assertRaises(Exception):
            a = Actor.remote()

        # Create an actor with too many arguments.
        with self.assertRaises(Exception):
            a = Actor.remote(1, 2)

        # Create an actor the correct number of arguments.
        a = Actor.remote(1)

        # Call a method with too few arguments.
        with self.assertRaises(Exception):
            a.get_val.remote()

        # Call a method with too many arguments.
        with self.assertRaises(Exception):
            a.get_val.remote(1, 2)
        # Call a method that doesn't exist.
        with self.assertRaises(AttributeError):
            a.nonexistent_method()
        with self.assertRaises(AttributeError):
            a.nonexistent_method.remote()

        ray.worker.cleanup()


class WorkerDeath(unittest.TestCase):

    def testWorkerDying(self):
        ray.init(num_workers=0, driver_mode=ray.SILENT_MODE)

        # Define a remote function that will kill the worker that runs it.
        @ray.remote
        def f():
            eval("exit()")

        f.remote()

        wait_for_errors(b"worker_died", 1)

        self.assertEqual(len(ray.error_info()), 1)
        self.assertIn("A worker died or was killed while executing a task.",
                      ray.error_info()[0][b"message"].decode("ascii"))

        ray.worker.cleanup()


class PutErrorTest(unittest.TestCase):

    def testPutError1(self):
        store_size = 10 ** 6
        ray.worker._init(start_ray_local=True, driver_mode=ray.SILENT_MODE,
                         object_store_memory=store_size)

        num_objects = 3
        object_size = 4 * 10 ** 5

        # Define a task with a single dependency, a numpy array, that returns
        # another array.
        @ray.remote
        def single_dependency(i, arg):
            arg = np.copy(arg)
            arg[0] = i
            return arg

        @ray.remote
        def put_arg_task():
            # Launch num_objects instances of the remote task, each dependent
            # on the one before it. The result of the first task should get
            # evicted.
            args = []
            arg = single_dependency.remote(0, np.zeros(object_size,
                                                       dtype=np.uint8))
            for i in range(num_objects):
                arg = single_dependency.remote(i, arg)
                args.append(arg)

            # Get the last value to force all tasks to finish.
            value = ray.get(args[-1])
            assert value[0] == i

            # Get the first value (which should have been evicted) to force
            # reconstruction. Currently, since we're not able to reconstruct
            # `ray.put` objects that were evicted and whose originating tasks
            # are still running, this for-loop should hang and push an error to
            # the driver.
            ray.get(args[0])

        put_arg_task.remote()

        # Make sure we receive the correct error message.
        wait_for_errors(b"put_reconstruction", 1)

        ray.worker.cleanup()

    def testPutError2(self):
        # This is the same as the previous test, but it calls ray.put directly.
        store_size = 10 ** 6
        ray.worker._init(start_ray_local=True, driver_mode=ray.SILENT_MODE,
                         object_store_memory=store_size)

        num_objects = 3
        object_size = 4 * 10 ** 5

        # Define a task with a single dependency, a numpy array, that returns
        # another array.
        @ray.remote
        def single_dependency(i, arg):
            arg = np.copy(arg)
            arg[0] = i
            return arg

        @ray.remote
        def put_task():
            # Launch num_objects instances of the remote task, each dependent
            # on the one before it. The result of the first task should get
            # evicted.
            args = []
            arg = ray.put(np.zeros(object_size, dtype=np.uint8))
            for i in range(num_objects):
                arg = single_dependency.remote(i, arg)
                args.append(arg)

            # Get the last value to force all tasks to finish.
            value = ray.get(args[-1])
            assert value[0] == i

            # Get the first value (which should have been evicted) to force
            # reconstruction. Currently, since we're not able to reconstruct
            # `ray.put` objects that were evicted and whose originating tasks
            # are still running, this for-loop should hang and push an error to
            # the driver.
            ray.get(args[0])

        put_task.remote()

        # Make sure we receive the correct error message.
        wait_for_errors(b"put_reconstruction", 1)

        ray.worker.cleanup()


if __name__ == "__main__":
    unittest.main(verbosity=2)