Drop all the `@cm.__exit__()` override attempts..

None of it worked (you still will see `.__exit__()` frames on debugger
entry - you'd think this would have been solved by now but, shrug) so
instead wrap the debugger entry-point in a `try:` and put the SIGINT
handler restoration inside `MultiActorPdb` teardown hooks.

This seems to restore the UX as it was prior but with also giving the
desired SIGINT override handler behaviour.
310_plus
Tyler Goodlet 2022-02-07 06:55:38 -05:00
parent 9a1dadecff
commit aa09a31d25
1 changed files with 164 additions and 162 deletions

View File

@ -24,16 +24,12 @@ import sys
import signal
from functools import partial
from contextlib import asynccontextmanager as acm
from contextlib import contextmanager as cm
from contextlib import _GeneratorContextManager
import contextlib
from typing import (
Tuple,
Optional,
Callable,
AsyncIterator,
AsyncGenerator,
Iterator,
)
import tractor
@ -58,19 +54,6 @@ except ImportError:
log = get_logger(__name__)
class noexittbGCM(_GeneratorContextManager):
# @pdb.hideframe
def __exit__(self, type, value, traceback):
__tracebackhide__ = True
# try:
return super().__exit__(type, value, traceback)
# except:
# print('EXITED')
contextlib._GeneratorContextManager = noexittbGCM
__all__ = ['breakpoint', 'post_mortem']
@ -103,9 +86,11 @@ class TractorConfig(pdbpp.DefaultConfig):
enable_hidden_frames = False
class PdbwTeardown(pdbpp.Pdb):
"""Add teardown hooks to the regular ``pdbpp.Pdb``.
"""
class MultiActorPdb(pdbpp.Pdb):
'''
Add teardown hooks to the regular ``pdbpp.Pdb``.
'''
# override the pdbpp config with our coolio one
DefaultConfig = TractorConfig
@ -172,7 +157,8 @@ async def _acquire_debug_lock(
uid: Tuple[str, str]
) -> AsyncIterator[trio.StrictFIFOLock]:
'''Acquire a root-actor local FIFO lock which tracks mutex access of
'''
Acquire a root-actor local FIFO lock which tracks mutex access of
the process tree's global debugger breakpoint.
This lock avoids tty clobbering (by preventing multiple processes
@ -269,6 +255,14 @@ async def _hijack_stdin_for_child(
log.debug(f"Actor {subactor_uid} is WAITING on stdin hijack lock")
orig_handler = signal.signal(
signal.SIGINT,
shield_sigint,
# partial(shield_sigint, pdb=pdb),
)
# try:
# yield
try:
with (
trio.CancelScope(shield=True),
# disable_sigint(),
@ -280,7 +274,9 @@ async def _hijack_stdin_for_child(
# indicate to child that we've locked stdio
await ctx.started('Locked')
log.debug(f"Actor {subactor_uid} acquired stdin hijack lock")
log.debug(
f"Actor {subactor_uid} acquired stdin hijack lock"
)
# wait for unlock pdb by child
async with ctx.open_stream() as stream:
@ -316,6 +312,12 @@ async def _hijack_stdin_for_child(
return "pdb_unlock_complete"
finally:
signal.signal(
signal.SIGINT,
orig_handler
)
async def wait_for_parent_stdin_hijack(
actor_uid: Tuple[str, str],
@ -361,12 +363,14 @@ async def wait_for_parent_stdin_hijack(
finally:
# TODO: shielding currently can cause hangs...
with trio.CancelScope(shield=True):
# with trio.CancelScope(shield=True):
await stream.send('pdb_unlock')
# sync with callee termination
assert await ctx.result() == "pdb_unlock_complete"
log.pdb('unlocked context')
except tractor.ContextCancelled:
log.warning('Root actor cancelled debug lock')
@ -398,6 +402,15 @@ async def _breakpoint(
# scope here???
# with trio.CancelScope(shield=shield):
pdb = MultiActorPdb()
signal.signal = pdbpp.hideframe(signal.signal)
orig_handler = signal.signal(
signal.SIGINT,
partial(shield_sigint, pdb_obj=pdb),
)
pdb.allow_kbdint = True
pdb.nosigint = True
actor = tractor.current_actor()
task_name = trio.lowlevel.current_task().name
@ -414,9 +427,12 @@ async def _breakpoint(
if _local_task_in_debug:
if _local_task_in_debug == task_name:
print("LOCAL TASK ALREADY IN DEBUG")
# this task already has the lock and is
# likely recurrently entering a breakpoint
return
else:
print("NOT LOCAL TASK ALREADY IN DEBUG")
# if **this** actor is already in debug mode block here
# waiting for the control to be released - this allows
@ -430,8 +446,18 @@ async def _breakpoint(
# entries/requests to the root process
_local_task_in_debug = task_name
def child_release_hook():
# _local_task_in_debug = None
_local_pdb_complete.set()
# restore original sigint handler
signal.signal(
signal.SIGINT,
orig_handler
)
# assign unlock callback for debugger teardown hooks
_pdb_release_hook = _local_pdb_complete.set
# _pdb_release_hook = _local_pdb_complete.set
_pdb_release_hook = child_release_hook
# this **must** be awaited by the caller and is done using the
# root nursery so that the debugger can continue to run without
@ -496,42 +522,49 @@ async def _breakpoint(
_local_task_in_debug = None
_local_pdb_complete.set()
# restore original sigint handler
signal.signal(
signal.SIGINT,
orig_handler
)
_pdb_release_hook = teardown
frame = sys._getframe()
last_f = frame.f_back
last_f.f_globals['__tracebackhide__'] = True
try:
# block here one (at the appropriate frame *up*) where
# ``breakpoint()`` was awaited and begin handling stdio.
log.debug("Entering the synchronous world of pdb")
debug_func(actor, pdb)
debug_func(actor)
@cm
@pdb.hideframe
def _open_pdb() -> Iterator[PdbwTeardown]:
# XXX: setting these flags on the pdb instance are absolutely
# critical to having ctrl-c work in the ``trio`` standard way! The
# stdlib's pdb supports entering the current sync frame on a SIGINT,
# with ``trio`` we pretty much never want this and if we did we can
# handle it in the ``tractor`` task runtime.
__tracebackhide__ = True
pdb = PdbwTeardown()
pdb.allow_kbdint = True
pdb.nosigint = True
try:
yield pdb
except bdb.BdbQuit:
if _pdb_release_hook:
_pdb_release_hook()
raise
# XXX: apparently we can't do this without showing this frame
# in the backtrace on first entry to the REPL? Seems like an odd
# behaviour that should have been fixed by now. This is also why
# we scrapped all the @cm approaches that were tried previously.
# finally:
# __tracebackhide__ = True
# # frame = sys._getframe()
# # last_f = frame.f_back
# # last_f.f_globals['__tracebackhide__'] = True
# # signal.signal = pdbpp.hideframe(signal.signal)
# signal.signal(
# signal.SIGINT,
# orig_handler
# )
def shield_sigint(
signum: int,
frame: 'frame', # type: ignore # noqa
pdb: Optional[PdbwTeardown] = None,
pdb_obj: Optional[MultiActorPdb] = None,
*args,
) -> None:
@ -543,6 +576,12 @@ def shield_sigint(
is always cancelled on ctrl-c.
'''
__tracebackhide__ = True
frame = sys._getframe()
last_f = frame.f_back
last_f.f_globals['__tracebackhide__'] = True
global _local_task_in_debug, _global_actor_in_debug
in_debug = _global_actor_in_debug
@ -598,68 +637,33 @@ def shield_sigint(
raise KeyboardInterrupt
# maybe redraw/print last REPL output to console
if pdb:
if pdb_obj:
# TODO: make this work like sticky mode where if there is output
# detected as written to the tty we redraw this part underneath
# and erase the past draw of this same bit above?
# pdb.sticky = True
# pdb._print_if_sticky()
# pdb_obj.sticky = True
# pdb_obj._print_if_sticky()
# also see these links for an approach from ``ptk``:
# https://github.com/goodboy/tractor/issues/130#issuecomment-663752040
# https://github.com/prompt-toolkit/python-prompt-toolkit/blob/c2c6af8a0308f9e5d7c0e28cb8a02963fe0ce07a/prompt_toolkit/patch_stdout.py
pdb.do_longlist(None)
print(pdb.prompt, end='', flush=True)
pdb_obj.do_longlist(None)
print(pdb_obj.prompt, end='', flush=True)
@pdb.hideframe
@cm
def disable_sigint(
pdb: Optional[PdbwTeardown] = None
) -> Iterator[None]:
__tracebackhide__ = True
# ensure the ``contextlib.contextmanager`` frame inside the wrapping
# ``.__exit__()`` method isn't shown either.
# frame = sys._getframe()
# last_f = frame.f_back
# last_f.f_globals['__tracebackhide__'] = True
# NOTE: this seems like a form of cpython bug wherein
# it's likely that ``functools.WRAPPER_ASSIGNMENTS`` should
# probably contain this attr name?
# for manual debugging if necessary
# pdb.set_trace()
orig_handler = signal.signal(
signal.SIGINT,
partial(shield_sigint, pdb=pdb),
)
try:
yield
finally:
signal.signal(
signal.SIGINT,
orig_handler
)
@pdb.hideframe
def _set_trace(
actor: Optional[tractor.Actor] = None
actor: Optional[tractor.Actor] = None,
pdb: Optional[MultiActorPdb] = None,
):
__tracebackhide__ = True
actor = actor or tractor.current_actor()
with (
_open_pdb() as pdb,
disable_sigint(pdb=pdb),
):
# frame = sys._getframe()
# last_f = frame.f_back
# last_f.f_globals['__tracebackhide__'] = True
if actor is not None:
log.pdb(f"\nAttaching pdb to actor: {actor.uid}\n")
@ -691,19 +695,17 @@ breakpoint = partial(
)
@pdb.hideframe
def _post_mortem(actor):
def _post_mortem(
actor: tractor.Actor,
pdb: MultiActorPdb,
__tracebackhide__ = True
) -> None:
'''
Enter the ``pdbpp`` port mortem entrypoint using our custom
debugger instance.
with (
# noop()
_open_pdb() as pdb,
# disable_sigint(pdb=pdb),
):
'''
log.pdb(f"\nAttaching to pdb in crashed actor: {actor.uid}\n")
# custom Pdb post-mortem entry
pdbpp.xpm(Pdb=lambda: pdb)