""" Cancellation and error propagation """ import os import signal import platform import time from itertools import repeat from exceptiongroup import ( BaseExceptionGroup, ExceptionGroup, ) import pytest import trio import tractor from conftest import tractor_test, no_windows def is_win(): return platform.system() == 'Windows' async def assert_err(delay=0): await trio.sleep(delay) assert 0 async def sleep_forever(): await trio.sleep_forever() async def do_nuthin(): # just nick the scheduler await trio.sleep(0) @pytest.mark.parametrize( 'args_err', [ # expected to be thrown in assert_err ({}, AssertionError), # argument mismatch raised in _invoke() ({'unexpected': 10}, TypeError) ], ids=['no_args', 'unexpected_args'], ) def test_remote_error(arb_addr, args_err): """Verify an error raised in a subactor that is propagated to the parent nursery, contains the underlying boxed builtin error type info and causes cancellation and reraising all the way up the stack. """ args, errtype = args_err async def main(): async with tractor.open_nursery( arbiter_addr=arb_addr, ) as nursery: # on a remote type error caused by bad input args # this should raise directly which means we **don't** get # an exception group outside the nursery since the error # here and the far end task error are one in the same? portal = await nursery.run_in_actor( assert_err, name='errorer', **args ) # get result(s) from main task try: # this means the root actor will also raise a local # parent task error and thus an eg will propagate out # of this actor nursery. await portal.result() except tractor.RemoteActorError as err: assert err.type == errtype print("Look Maa that actor failed hard, hehh") raise # ensure boxed errors if args: with pytest.raises(tractor.RemoteActorError) as excinfo: trio.run(main) assert excinfo.value.type == errtype else: # the root task will also error on the `.result()` call # so we expect an error from there AND the child. with pytest.raises(BaseExceptionGroup) as excinfo: trio.run(main) # ensure boxed errors for exc in excinfo.value.exceptions: assert exc.type == errtype def test_multierror(arb_addr): ''' Verify we raise a ``BaseExceptionGroup`` out of a nursery where more then one actor errors. ''' async def main(): async with tractor.open_nursery( arbiter_addr=arb_addr, ) as nursery: await nursery.run_in_actor(assert_err, name='errorer1') portal2 = await nursery.run_in_actor(assert_err, name='errorer2') # get result(s) from main task try: await portal2.result() except tractor.RemoteActorError as err: assert err.type == AssertionError print("Look Maa that first actor failed hard, hehh") raise # here we should get a ``BaseExceptionGroup`` containing exceptions # from both subactors with pytest.raises(BaseExceptionGroup): trio.run(main) @pytest.mark.parametrize('delay', (0, 0.5)) @pytest.mark.parametrize( 'num_subactors', range(25, 26), ) def test_multierror_fast_nursery(arb_addr, start_method, num_subactors, delay): """Verify we raise a ``BaseExceptionGroup`` out of a nursery where more then one actor errors and also with a delay before failure to test failure during an ongoing spawning. """ async def main(): async with tractor.open_nursery( arbiter_addr=arb_addr, ) as nursery: for i in range(num_subactors): await nursery.run_in_actor( assert_err, name=f'errorer{i}', delay=delay ) # with pytest.raises(trio.MultiError) as exc_info: with pytest.raises(BaseExceptionGroup) as exc_info: trio.run(main) assert exc_info.type == ExceptionGroup err = exc_info.value exceptions = err.exceptions if len(exceptions) == 2: # sometimes oddly now there's an embedded BrokenResourceError ? for exc in exceptions: excs = getattr(exc, 'exceptions', None) if excs: exceptions = excs break assert len(exceptions) == num_subactors for exc in exceptions: assert isinstance(exc, tractor.RemoteActorError) assert exc.type == AssertionError async def do_nothing(): pass @pytest.mark.parametrize('mechanism', ['nursery_cancel', KeyboardInterrupt]) def test_cancel_single_subactor(arb_addr, mechanism): """Ensure a ``ActorNursery.start_actor()`` spawned subactor cancels when the nursery is cancelled. """ async def spawn_actor(): """Spawn an actor that blocks indefinitely. """ async with tractor.open_nursery( arbiter_addr=arb_addr, ) as nursery: portal = await nursery.start_actor( 'nothin', enable_modules=[__name__], ) assert (await portal.run(do_nothing)) is None if mechanism == 'nursery_cancel': # would hang otherwise await nursery.cancel() else: raise mechanism if mechanism == 'nursery_cancel': trio.run(spawn_actor) else: with pytest.raises(mechanism): trio.run(spawn_actor) async def stream_forever(): for i in repeat("I can see these little future bubble things"): # each yielded value is sent over the ``Channel`` to the # parent actor yield i await trio.sleep(0.01) @tractor_test async def test_cancel_infinite_streamer(start_method): # stream for at most 1 seconds with trio.move_on_after(1) as cancel_scope: async with tractor.open_nursery() as n: portal = await n.start_actor( 'donny', enable_modules=[__name__], ) # this async for loop streams values from the above # async generator running in a separate process async with portal.open_stream_from(stream_forever) as stream: async for letter in stream: print(letter) # we support trio's cancellation system assert cancel_scope.cancelled_caught assert n.cancelled @pytest.mark.parametrize( 'num_actors_and_errs', [ # daemon actors sit idle while single task actors error out (1, tractor.RemoteActorError, AssertionError, (assert_err, {}), None), (2, BaseExceptionGroup, AssertionError, (assert_err, {}), None), (3, BaseExceptionGroup, AssertionError, (assert_err, {}), None), # 1 daemon actor errors out while single task actors sleep forever (3, tractor.RemoteActorError, AssertionError, (sleep_forever, {}), (assert_err, {}, True)), # daemon actors error out after brief delay while single task # actors complete quickly (3, tractor.RemoteActorError, AssertionError, (do_nuthin, {}), (assert_err, {'delay': 1}, True)), # daemon complete quickly delay while single task # actors error after brief delay (3, BaseExceptionGroup, AssertionError, (assert_err, {'delay': 1}), (do_nuthin, {}, False)), ], ids=[ '1_run_in_actor_fails', '2_run_in_actors_fail', '3_run_in_actors_fail', '1_daemon_actors_fail', '1_daemon_actors_fail_all_run_in_actors_dun_quick', 'no_daemon_actors_fail_all_run_in_actors_sleep_then_fail', ], ) @tractor_test async def test_some_cancels_all(num_actors_and_errs, start_method, loglevel): """Verify a subset of failed subactors causes all others in the nursery to be cancelled just like the strategy in trio. This is the first and only supervisory strategy at the moment. """ num_actors, first_err, err_type, ria_func, da_func = num_actors_and_errs try: async with tractor.open_nursery() as n: # spawn the same number of deamon actors which should be cancelled dactor_portals = [] for i in range(num_actors): dactor_portals.append(await n.start_actor( f'deamon_{i}', enable_modules=[__name__], )) func, kwargs = ria_func riactor_portals = [] for i in range(num_actors): # start actor(s) that will fail immediately riactor_portals.append( await n.run_in_actor( func, name=f'actor_{i}', **kwargs ) ) if da_func: func, kwargs, expect_error = da_func for portal in dactor_portals: # if this function fails then we should error here # and the nursery should teardown all other actors try: await portal.run(func, **kwargs) except tractor.RemoteActorError as err: assert err.type == err_type # we only expect this first error to propogate # (all other daemons are cancelled before they # can be scheduled) num_actors = 1 # reraise so nursery teardown is triggered raise else: if expect_error: pytest.fail( "Deamon call should fail at checkpoint?") # should error here with a ``RemoteActorError`` or ``MultiError`` except first_err as err: if isinstance(err, BaseExceptionGroup): assert len(err.exceptions) == num_actors for exc in err.exceptions: if isinstance(exc, tractor.RemoteActorError): assert exc.type == err_type else: assert isinstance(exc, trio.Cancelled) elif isinstance(err, tractor.RemoteActorError): assert err.type == err_type assert n.cancelled is True assert not n._children else: pytest.fail("Should have gotten a remote assertion error?") async def spawn_and_error(breadth, depth) -> None: name = tractor.current_actor().name async with tractor.open_nursery() as nursery: for i in range(breadth): if depth > 0: args = ( spawn_and_error, ) kwargs = { 'name': f'spawner_{i}_depth_{depth}', 'breadth': breadth, 'depth': depth - 1, } else: args = ( assert_err, ) kwargs = { 'name': f'{name}_errorer_{i}', } await nursery.run_in_actor(*args, **kwargs) @tractor_test async def test_nested_multierrors(loglevel, start_method): ''' Test that failed actor sets are wrapped in `BaseExceptionGroup`s. This test goes only 2 nurseries deep but we should eventually have tests for arbitrary n-depth actor trees. ''' if start_method == 'trio': depth = 3 subactor_breadth = 2 else: # XXX: multiprocessing can't seem to handle any more then 2 depth # process trees for whatever reason. # Any more process levels then this and we see bugs that cause # hangs and broken pipes all over the place... if start_method == 'forkserver': pytest.skip("Forksever sux hard at nested spawning...") depth = 1 # means an additional actor tree of spawning (2 levels deep) subactor_breadth = 2 with trio.fail_after(120): try: async with tractor.open_nursery() as nursery: for i in range(subactor_breadth): await nursery.run_in_actor( spawn_and_error, name=f'spawner_{i}', breadth=subactor_breadth, depth=depth, ) except BaseExceptionGroup as err: assert len(err.exceptions) == subactor_breadth for subexc in err.exceptions: # verify first level actor errors are wrapped as remote if is_win(): # windows is often too slow and cancellation seems # to happen before an actor is spawned if isinstance(subexc, trio.Cancelled): continue elif isinstance(subexc, tractor.RemoteActorError): # on windows it seems we can't exactly be sure wtf # will happen.. assert subexc.type in ( tractor.RemoteActorError, trio.Cancelled, BaseExceptionGroup, ) elif isinstance(subexc, BaseExceptionGroup): for subsub in subexc.exceptions: if subsub in (tractor.RemoteActorError,): subsub = subsub.type assert type(subsub) in ( trio.Cancelled, BaseExceptionGroup, ) else: assert isinstance(subexc, tractor.RemoteActorError) if depth > 0 and subactor_breadth > 1: # XXX not sure what's up with this.. # on windows sometimes spawning is just too slow and # we get back the (sent) cancel signal instead if is_win(): if isinstance(subexc, tractor.RemoteActorError): assert subexc.type in ( BaseExceptionGroup, tractor.RemoteActorError ) else: assert isinstance(subexc, BaseExceptionGroup) else: assert subexc.type is ExceptionGroup else: assert subexc.type in ( tractor.RemoteActorError, trio.Cancelled ) @no_windows def test_cancel_via_SIGINT( loglevel, start_method, spawn_backend, ): """Ensure that a control-C (SIGINT) signal cancels both the parent and child processes in trionic fashion """ pid = os.getpid() async def main(): with trio.fail_after(2): async with tractor.open_nursery() as tn: await tn.start_actor('sucka') if 'mp' in spawn_backend: time.sleep(0.1) os.kill(pid, signal.SIGINT) await trio.sleep_forever() with pytest.raises(KeyboardInterrupt): trio.run(main) @no_windows def test_cancel_via_SIGINT_other_task( loglevel, start_method, spawn_backend, ): """Ensure that a control-C (SIGINT) signal cancels both the parent and child processes in trionic fashion even a subprocess is started from a seperate ``trio`` child task. """ pid = os.getpid() timeout: float = 2 if is_win(): # smh timeout += 1 async def spawn_and_sleep_forever(task_status=trio.TASK_STATUS_IGNORED): async with tractor.open_nursery() as tn: for i in range(3): await tn.run_in_actor( sleep_forever, name='namesucka', ) task_status.started() await trio.sleep_forever() async def main(): # should never timeout since SIGINT should cancel the current program with trio.fail_after(timeout): async with trio.open_nursery() as n: await n.start(spawn_and_sleep_forever) if 'mp' in spawn_backend: time.sleep(0.1) os.kill(pid, signal.SIGINT) with pytest.raises(KeyboardInterrupt): trio.run(main) async def spin_for(period=3): "Sync sleep." time.sleep(period) async def spawn(): async with tractor.open_nursery() as tn: await tn.run_in_actor( spin_for, name='sleeper', ) @no_windows def test_cancel_while_childs_child_in_sync_sleep( loglevel, start_method, spawn_backend, ): """Verify that a child cancelled while executing sync code is torn down even when that cancellation is triggered by the parent 2 nurseries "up". """ if start_method == 'forkserver': pytest.skip("Forksever sux hard at resuming from sync sleep...") async def main(): with trio.fail_after(2): async with tractor.open_nursery() as tn: await tn.run_in_actor( spawn, name='spawn', ) await trio.sleep(1) assert 0 with pytest.raises(AssertionError): trio.run(main) def test_fast_graceful_cancel_when_spawn_task_in_soft_proc_wait_for_daemon( start_method, ): ''' This is a very subtle test which demonstrates how cancellation during process collection can result in non-optimal teardown performance on daemon actors. The fix for this test was to handle ``trio.Cancelled`` specially in the spawn task waiting in `proc.wait()` such that ``Portal.cancel_actor()`` is called before executing the "hard reap" sequence (which has an up to 3 second delay currently). In other words, if we can cancel the actor using a graceful remote cancellation, and it's faster, we might as well do it. ''' kbi_delay = 0.5 timeout: float = 2.9 if is_win(): # smh timeout += 1 async def main(): start = time.time() try: async with trio.open_nursery() as nurse: async with tractor.open_nursery() as tn: p = await tn.start_actor( 'fast_boi', enable_modules=[__name__], ) async def delayed_kbi(): await trio.sleep(kbi_delay) print(f'RAISING KBI after {kbi_delay} s') raise KeyboardInterrupt # start task which raises a kbi **after** # the actor nursery ``__aexit__()`` has # been run. nurse.start_soon(delayed_kbi) await p.run(do_nuthin) finally: duration = time.time() - start if duration > timeout: raise trio.TooSlowError( 'daemon cancel was slower then necessary..' ) with pytest.raises(KeyboardInterrupt): trio.run(main)