From 11bbf15817980f69aea39d0742e5e1fb8f32a1a8 Mon Sep 17 00:00:00 2001
From: Tyler Goodlet <jgbt@protonmail.com>
Date: Mon, 16 Oct 2023 16:23:30 -0400
Subject: [PATCH] `._exceptions`: typing and error unpacking updates
Bump type annotations to 3.10+ style throughout module as well as fill
out doc strings a bit. Inside `unpack_error()` pop any `error_dict: dict`
and,
- return `None` early if not found,
- versus pass directly as `**error_dict` to the error constructor
instead of a double field read.
---
tractor/_exceptions.py | 53 ++++++++++++++++++++++++++++--------------
1 file changed, 35 insertions(+), 18 deletions(-)
diff --git a/tractor/_exceptions.py b/tractor/_exceptions.py
index 9de27bdf..d9e1d17f 100644
--- a/tractor/_exceptions.py
+++ b/tractor/_exceptions.py
@@ -113,18 +113,24 @@ class AsyncioCancelled(Exception):
def pack_error(
exc: BaseException,
- tb=None,
+ tb: str | None = None,
-) -> dict[str, Any]:
- """Create an "error message" for tranmission over
- a channel (aka the wire).
- """
+) -> dict[str, dict]:
+ '''
+ Create an "error message" encoded for wire transport via an IPC
+ `Channel`; expected to be unpacked on the receiver side using
+ `unpack_error()` below.
+
+ '''
if tb:
tb_str = ''.join(traceback.format_tb(tb))
else:
tb_str = traceback.format_exc()
- error_msg = {
+ error_msg: dict[
+ str,
+ str | tuple[str, str]
+ ] = {
'tb_str': tb_str,
'type_str': type(exc).__name__,
'src_actor_uid': current_actor().uid,
@@ -142,18 +148,28 @@ def unpack_error(
chan=None,
err_type=RemoteActorError
-) -> Exception:
+) -> None | Exception:
'''
Unpack an 'error' message from the wire
- into a local ``RemoteActorError``.
+ into a local `RemoteActorError` (subtype).
+
+ NOTE: this routine DOES not RAISE the embedded remote error,
+ which is the responsibilitiy of the caller.
'''
- __tracebackhide__ = True
- error = msg['error']
+ __tracebackhide__: bool = True
- tb_str = error.get('tb_str', '')
- message = f'{chan.uid}\n' + tb_str
- type_name = error['type_str']
+ error_dict: dict[str, dict] | None
+ if (
+ error_dict := msg.get('error')
+ ) is None:
+ # no error field, nothing to unpack.
+ return None
+
+ # retrieve the remote error's msg encoded details
+ tb_str: str = error_dict.get('tb_str', '')
+ message: str = f'{chan.uid}\n' + tb_str
+ type_name: str = error_dict['type_str']
suberror_type: Type[BaseException] = Exception
if type_name == 'ContextCancelled':
@@ -167,18 +183,19 @@ def unpack_error(
eg,
trio,
]:
- try:
- suberror_type = getattr(ns, type_name)
+ if suberror_type := getattr(
+ ns,
+ type_name,
+ False,
+ ):
break
- except AttributeError:
- continue
exc = err_type(
message,
suberror_type=suberror_type,
# unpack other fields into error type init
- **msg['error'],
+ **error_dict,
)
return exc