forked from goodboy/tractor
Ensure user-allocated cancel scope just works!
Turns out the nursery doesn't have to care about allocating a per task
`CancelScope` since the user can just do that in the
`@task_scope_manager` if desired B) So just mask all the nursery cs
allocating with the intention of removal.
Also add a test for per-task-cancellation by starting the crash task as
a `trio.sleep_forever()` but then cancel it via the user allocated cs
and ensure the crash propagates as expected 💥
oco_supervisor_prototype
parent
f23b5b89dd
commit
56882b680c
|
@ -126,18 +126,23 @@ class ScopePerTaskNursery(Struct):
|
|||
# task = new_tasks.pop()
|
||||
|
||||
n: Nursery = self._n
|
||||
cs = CancelScope()
|
||||
|
||||
sm = self.scope_manager
|
||||
# we do default behavior of a scope-per-nursery
|
||||
# if the user did not provide a task manager.
|
||||
if sm is None:
|
||||
return n.start_soon(async_fn, *args, name=None)
|
||||
|
||||
# per_task_cs = CancelScope()
|
||||
new_task: Task | None = None
|
||||
to_return: tuple[Any] | None = None
|
||||
|
||||
sm = self.scope_manager
|
||||
if sm is None:
|
||||
mngr = nullcontext([cs])
|
||||
else:
|
||||
# NOTE: what do we enforce as a signature for the
|
||||
# `@task_scope_manager` here?
|
||||
mngr = sm(nursery=n)
|
||||
|
||||
mngr = sm(
|
||||
nursery=n,
|
||||
# scope=per_task_cs,
|
||||
)
|
||||
async def _start_wrapped_in_scope(
|
||||
task_status: TaskStatus[
|
||||
tuple[CancelScope, Task]
|
||||
|
@ -148,10 +153,12 @@ class ScopePerTaskNursery(Struct):
|
|||
# TODO: this was working before?!
|
||||
# nonlocal to_return
|
||||
|
||||
with cs:
|
||||
|
||||
task = trio.lowlevel.current_task()
|
||||
self._scopes[cs] = task
|
||||
# self._scopes[per_task_cs] = task
|
||||
|
||||
# NOTE: we actually don't need this since the user can
|
||||
# just to it themselves inside mngr!
|
||||
# with per_task_cs:
|
||||
|
||||
# execute up to the first yield
|
||||
try:
|
||||
|
@ -178,8 +185,7 @@ class ScopePerTaskNursery(Struct):
|
|||
try:
|
||||
mngr.send(outcome)
|
||||
|
||||
# NOTE: this will instead send the underlying
|
||||
# `.value`? Not sure if that's better or not?
|
||||
|
||||
# I would presume it's better to have a handle to
|
||||
# the `Outcome` entirely? This method sends *into*
|
||||
# the mngr this `Outcome.value`; seems like kinda
|
||||
|
@ -200,7 +206,6 @@ class ScopePerTaskNursery(Struct):
|
|||
return to_return
|
||||
|
||||
|
||||
|
||||
# TODO: you could wrap your output task handle in this?
|
||||
# class TaskHandle(Struct):
|
||||
# task: Task
|
||||
|
@ -214,6 +219,11 @@ class ScopePerTaskNursery(Struct):
|
|||
def add_task_handle_and_crash_handling(
|
||||
nursery: Nursery,
|
||||
|
||||
# TODO: is this the only way we can have a per-task scope
|
||||
# allocated or can we allow the user to somehow do it if
|
||||
# they want below?
|
||||
# scope: CancelScope,
|
||||
|
||||
) -> Generator[None, list[Any]]:
|
||||
|
||||
task_outcome = TaskOutcome()
|
||||
|
@ -222,8 +232,12 @@ def add_task_handle_and_crash_handling(
|
|||
task: Task = trio.lowlevel.current_task()
|
||||
print(f'Spawning task: {task.name}')
|
||||
|
||||
# yields back when task is terminated, cancelled, returns.
|
||||
try:
|
||||
# yields back when task is terminated, cancelled, returns?
|
||||
# XXX: wait, this isn't doing anything right since we'd have to
|
||||
# manually activate this scope using something like:
|
||||
# `task._activate_cancel_status(cs._cancel_status)` ??
|
||||
# oh wait, but `.__enter__()` does all that already?
|
||||
with CancelScope() as cs:
|
||||
|
||||
# the yielded value(s) here are what are returned to the
|
||||
|
@ -260,6 +274,19 @@ async def sleep_then_return_val(val: str):
|
|||
return val
|
||||
|
||||
|
||||
async def ensure_cancelled():
|
||||
try:
|
||||
await trio.sleep_forever()
|
||||
|
||||
except trio.Cancelled:
|
||||
task = trio.lowlevel.current_task()
|
||||
print(f'heyyo ONLY {task.name} was cancelled as expected B)')
|
||||
assert 0
|
||||
|
||||
except BaseException:
|
||||
raise RuntimeError("woa woa woa this ain't right!")
|
||||
|
||||
|
||||
if __name__ == '__main__':
|
||||
|
||||
async def main():
|
||||
|
@ -267,17 +294,22 @@ if __name__ == '__main__':
|
|||
scope_manager=add_task_handle_and_crash_handling,
|
||||
) as sn:
|
||||
for _ in range(3):
|
||||
outcome, cs = await sn.start_soon(trio.sleep_forever)
|
||||
outcome, _ = await sn.start_soon(trio.sleep_forever)
|
||||
|
||||
# extra task we want to engage in debugger post mortem.
|
||||
err_outcome, *_ = await sn.start_soon(sleep_then_err)
|
||||
err_outcome, cs = await sn.start_soon(ensure_cancelled)
|
||||
|
||||
val: str = 'yoyoyo'
|
||||
val_outcome, cs = await sn.start_soon(sleep_then_return_val, val)
|
||||
val_outcome, _ = await sn.start_soon(
|
||||
sleep_then_return_val,
|
||||
val,
|
||||
)
|
||||
res = await val_outcome.wait_for_result()
|
||||
assert res == val
|
||||
print(f'GOT EXPECTED TASK VALUE: {res}')
|
||||
print(f'{res} -> GOT EXPECTED TASK VALUE')
|
||||
|
||||
print('WAITING FOR CRASH..')
|
||||
await trio.sleep(0.6)
|
||||
print('Cancelling and waiting for CRASH..')
|
||||
cs.cancel()
|
||||
|
||||
trio.run(main)
|
||||
|
|
Loading…
Reference in New Issue