From dbff7e6cd00dc864d07e37424b136e38a93397aa Mon Sep 17 00:00:00 2001
From: Tyler Goodlet <jgbt@protonmail.com>
Date: Mon, 26 Aug 2024 14:29:09 -0400
Subject: [PATCH] Report any external-rent-task-canceller during msg-drain
As in whenever `Context.cancel()` is not (runtime internally) called
(i.e. `._cancel_called` is not set), we can attempt to detect the parent
`trio` nursery/cancel-scope that is the source. Emit the report with
a `.cancel()` level and attempt to repr in "sclang" form as well as
unhide the stack frame for debug/traceback-in.
---
tractor/msg/_ops.py | 27 ++++++++++++++++++++++++---
1 file changed, 24 insertions(+), 3 deletions(-)
diff --git a/tractor/msg/_ops.py b/tractor/msg/_ops.py
index f0f3b6b2..2faadb9f 100644
--- a/tractor/msg/_ops.py
+++ b/tractor/msg/_ops.py
@@ -590,15 +590,36 @@ async def drain_to_final_msg(
# SHOULD NOT raise that far end error,
# 2. WE DID NOT REQUEST that cancel and thus
# SHOULD RAISE HERE!
- except trio.Cancelled as taskc:
+ except trio.Cancelled as _taskc:
+ taskc: trio.Cancelled = _taskc
+
+ # report when the cancellation wasn't (ostensibly) due to
+ # RPC operation, some surrounding parent cancel-scope.
+ if not ctx._scope.cancel_called:
+ task: trio.lowlevel.Task = trio.lowlevel.current_task()
+ rent_n: trio.Nursery = task.parent_nursery
+ if (
+ (local_cs := rent_n.cancel_scope).cancel_called
+ ):
+ log.cancel(
+ 'RPC-ctx cancelled by local-parent scope during drain!\n\n'
+ f'c}}>\n'
+ f' |_{rent_n}\n'
+ f' |_.cancel_scope = {local_cs}\n'
+ f' |_>c}}\n'
+ f' |_{ctx.pformat(indent=" "*9)}'
+ # ^TODO, some (other) simpler repr here?
+ )
+ __tracebackhide__: bool = False
+
# CASE 2: mask the local cancelled-error(s)
# only when we are sure the remote error is
# the source cause of this local task's
# cancellation.
ctx.maybe_raise(
hide_tb=hide_tb,
- # TODO: when use this?
- # from_src_exc=taskc,
+ from_src_exc=taskc,
+ # ?TODO? when *should* we use this?
)
# CASE 1: we DID request the cancel we simply