jc211
/
tractor
forked from goodboy/tractor
1
0
Fork 0
Code Pull Requests Activity

Make OCA nursery **not** a multiplexed mindfuck

zombie_lord_infinite
Tyler Goodlet 2021-10-08 18:18:00 -04:00
parent 64ebb2aff4
commit 7250deb30f
1 changed files with 85 additions and 169 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

162
tractor/_supervise.py
View File

@ -12,6 +12,7 @@ import trio
from async_generator import asynccontextmanager from async_generator import asynccontextmanager
from . import _debug from . import _debug
from ._debug import maybe_wait_for_debugger
from ._state import current_actor, is_main_process, is_root_process from ._state import current_actor, is_main_process, is_root_process
from .log import get_logger, get_loglevel from .log import get_logger, get_loglevel
from ._actor import Actor from ._actor import Actor
@ -50,6 +51,7 @@ class ActorNursery:
self._cancel_after_result_on_exit: set = set() self._cancel_after_result_on_exit: set = set()
self.cancelled: bool = False self.cancelled: bool = False
self._join_procs = trio.Event() self._join_procs = trio.Event()
self._all_children_reaped = trio.Event()
self.errors = errors self.errors = errors
async def start_actor( async def start_actor(
@ -168,8 +170,11 @@ class ActorNursery:
) )
return portal return portal
async def cancel(self, hard_kill: bool = False) -> None: async def cancel(
"""Cancel this nursery by instructing each subactor to cancel self,
) -> None:
"""
Cancel this nursery by instructing each subactor to cancel
itself and wait for all subactors to terminate. itself and wait for all subactors to terminate.
If ``hard_killl`` is set to ``True`` then kill the processes If ``hard_killl`` is set to ``True`` then kill the processes
@ -177,58 +182,20 @@ class ActorNursery:
""" """
self.cancelled = True self.cancelled = True
log.cancel(f"Cancelling nursery in {self._actor.uid}") childs = tuple(self._children.keys())
with trio.move_on_after(3) as cs: log.cancel(
f"Cancelling nursery in {self._actor.uid} with children\n{childs}"
)
async with trio.open_nursery() as nursery: await maybe_wait_for_debugger()
for subactor, proc, portal in self._children.values(): # wake up all spawn tasks
# TODO: are we ever even going to use this or
# is the spawning backend responsible for such
# things? I'm thinking latter.
if hard_kill:
proc.terminate()
else:
if portal is None: # actor hasn't fully spawned yet
event = self._actor._peer_connected[subactor.uid]
log.warning(
f"{subactor.uid} wasn't finished spawning?")
await event.wait()
# channel/portal should now be up
_, _, portal = self._children[subactor.uid]
# XXX should be impossible to get here
# unless method was called from within
# shielded cancel scope.
if portal is None:
# cancelled while waiting on the event
# to arrive
chan = self._actor._peers[subactor.uid][-1]
if chan:
portal = Portal(chan)
else: # there's no other choice left
proc.terminate()
# spawn cancel tasks for each sub-actor
assert portal
nursery.start_soon(portal.cancel_actor)
# if we cancelled the cancel (we hung cancelling remote actors)
# then hard kill all sub-processes
if cs.cancelled_caught:
log.error(
f"Failed to cancel {self}\nHard killing process tree!")
for subactor, proc, portal in self._children.values():
log.warning(f"Hard killing process {proc}")
proc.terminate()
# mark ourselves as having (tried to have) cancelled all subactors
self._join_procs.set() self._join_procs.set()
# cancel all spawner nurseries
self._ria_nursery.cancel_scope.cancel()
self._da_nursery.cancel_scope.cancel()
@asynccontextmanager @asynccontextmanager
async def _open_and_supervise_one_cancels_all_nursery( async def _open_and_supervise_one_cancels_all_nursery(
@ -244,10 +211,13 @@ async def _open_and_supervise_one_cancels_all_nursery(
# a supervisor strategy **before** blocking indefinitely to wait for # a supervisor strategy **before** blocking indefinitely to wait for
# actors spawned in "daemon mode" (aka started using # actors spawned in "daemon mode" (aka started using
# ``ActorNursery.start_actor()``). # ``ActorNursery.start_actor()``).
original_err = None
# errors from this daemon actor nursery bubble up to caller # errors from this daemon actor nursery bubble up to caller
async with trio.open_nursery() as da_nursery:
try: try:
async with trio.open_nursery() as da_nursery:
# try:
# This is the inner level "run in actor" nursery. It is # This is the inner level "run in actor" nursery. It is
# awaited first since actors spawned in this way (using # awaited first since actors spawned in this way (using
# ``ActorNusery.run_in_actor()``) are expected to only # ``ActorNusery.run_in_actor()``) are expected to only
@ -256,6 +226,7 @@ async def _open_and_supervise_one_cancels_all_nursery(
# immediately raised for handling by a supervisor strategy. # immediately raised for handling by a supervisor strategy.
# As such if the strategy propagates any error(s) upwards # As such if the strategy propagates any error(s) upwards
# the above "daemon actor" nursery will be notified. # the above "daemon actor" nursery will be notified.
try:
async with trio.open_nursery() as ria_nursery: async with trio.open_nursery() as ria_nursery:
anursery = ActorNursery( anursery = ActorNursery(
@ -264,7 +235,6 @@ async def _open_and_supervise_one_cancels_all_nursery(
da_nursery, da_nursery,
errors errors
) )
try:
# spawning of actors happens in the caller's scope # spawning of actors happens in the caller's scope
# after we yield upwards # after we yield upwards
yield anursery yield anursery
@ -274,48 +244,15 @@ async def _open_and_supervise_one_cancels_all_nursery(
"to complete" "to complete"
) )
# Last bit before first nursery block ends in the case
# where we didn't error in the caller's scope
# signal all process monitor tasks to conduct # signal all process monitor tasks to conduct
# hard join phase. # hard join phase.
# await maybe_wait_for_debugger()
# log.error('joing trigger NORMAL')
anursery._join_procs.set() anursery._join_procs.set()
except BaseException as err: except BaseException as err:
original_err = err
# If we error in the root but the debugger is
# engaged we don't want to prematurely kill (and
# thus clobber access to) the local tty since it
# will make the pdb repl unusable.
# Instead try to wait for pdb to be released before
# tearing down.
if is_root_process():
# TODO: could this make things more deterministic?
# wait to see if a sub-actor task will be
# scheduled and grab the tty lock on the next
# tick?
# await trio.testing.wait_all_tasks_blocked()
debug_complete = _debug._no_remote_has_tty
if (
debug_complete and
not debug_complete.is_set()
):
log.warning(
'Root has errored but pdb is in use by '
f'child {_debug._global_actor_in_debug}\n'
'Waiting on tty lock to release..')
with trio.CancelScope(shield=True):
await debug_complete.wait()
# if the caller's scope errored then we activate our
# one-cancels-all supervisor strategy (don't
# worry more are coming).
anursery._join_procs.set()
try:
# XXX: hypothetically an error could be # XXX: hypothetically an error could be
# raised and then a cancel signal shows up # raised and then a cancel signal shows up
# slightly after in which case the `else:` # slightly after in which case the `else:`
@ -323,6 +260,7 @@ async def _open_and_supervise_one_cancels_all_nursery(
# shield both. # shield both.
with trio.CancelScope(shield=True): with trio.CancelScope(shield=True):
etype = type(err) etype = type(err)
if etype in ( if etype in (
trio.Cancelled, trio.Cancelled,
KeyboardInterrupt KeyboardInterrupt
@ -340,38 +278,12 @@ async def _open_and_supervise_one_cancels_all_nursery(
# cancel all subactors # cancel all subactors
await anursery.cancel() await anursery.cancel()
except trio.MultiError as merr: # ria_nursery scope end - nursery checkpoint
# If we receive additional errors while waiting on
# remaining subactors that were cancelled,
# aggregate those errors with the original error
# that triggered this teardown.
if err not in merr.exceptions:
raise trio.MultiError(merr.exceptions + [err])
else:
raise
# ria_nursery scope end # after daemon nursery exit
# XXX: do we need a `trio.Cancelled` catch here as well?
# this is the catch around the ``.run_in_actor()`` nursery
except (
Exception,
trio.MultiError,
trio.Cancelled
) as err:
# If actor-local error was raised while waiting on
# ".run_in_actor()" actors then we also want to cancel all
# remaining sub-actors (due to our lone strategy:
# one-cancels-all).
log.cancel(f"Nursery cancelling due to {err}")
if anursery._children:
with trio.CancelScope(shield=True):
await anursery.cancel()
raise
finally: finally:
with trio.CancelScope(shield=True):
await anursery._all_children_reaped.wait()
# No errors were raised while awaiting ".run_in_actor()" # No errors were raised while awaiting ".run_in_actor()"
# actors but those actors may have returned remote errors as # actors but those actors may have returned remote errors as
# results (meaning they errored remotely and have relayed # results (meaning they errored remotely and have relayed
@ -380,8 +292,9 @@ async def _open_and_supervise_one_cancels_all_nursery(
# all errors and re-raise. # all errors and re-raise.
if errors: if errors:
if anursery._children: if anursery._children:
with trio.CancelScope(shield=True): raise RuntimeError("WHERE TF IS THE ZOMBIE LORD!?!?!")
await anursery.cancel() # with trio.CancelScope(shield=True):
# await anursery.cancel()
# use `MultiError` as needed # use `MultiError` as needed
if len(errors) > 1: if len(errors) > 1:
@ -389,16 +302,18 @@ async def _open_and_supervise_one_cancels_all_nursery(
else: else:
raise list(errors.values())[0] raise list(errors.values())[0]
# ria_nursery scope end - nursery checkpoint elif original_err:
raise original_err
# after nursery exit log.cancel(f'{anursery} terminated gracefully')
@asynccontextmanager @asynccontextmanager
async def open_nursery( async def open_nursery(
**kwargs, **kwargs,
) -> typing.AsyncGenerator[ActorNursery, None]: ) -> typing.AsyncGenerator[ActorNursery, None]:
"""Create and yield a new ``ActorNursery`` to be used for spawning """
Create and yield a new ``ActorNursery`` to be used for spawning
structured concurrent subactors. structured concurrent subactors.
When an actor is spawned a new trio task is started which When an actor is spawned a new trio task is started which
@ -410,6 +325,7 @@ async def open_nursery(
close it. It turns out this approach is probably more correct close it. It turns out this approach is probably more correct
anyway since it is more clear from the following nested nurseries anyway since it is more clear from the following nested nurseries
which cancellation scopes correspond to each spawned subactor set. which cancellation scopes correspond to each spawned subactor set.
""" """
implicit_runtime = False implicit_runtime = False