[issue45828] [sqlite3] use unraisable exceptions in callbacks

[Erlend E. Aasland]

Change by Erlend E. Aasland :


--
resolution:  -> fixed
stage: patch review -> resolved
status: open -> closed

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue45828] [sqlite3] use unraisable exceptions in callbacks

[Pablo Galindo Salgado]

Pablo Galindo Salgado  added the comment:


New changeset c4a69a4ad035513ada1c0d41a46723606b538e13 by Erlend Egeberg 
Aasland in branch 'main':
bpo-45828: Use unraisable exceptions within sqlite3 callbacks (FH-29591)
https://github.com/python/cpython/commit/c4a69a4ad035513ada1c0d41a46723606b538e13


--
nosy: +pablogsal

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue45828] [sqlite3] use unraisable exceptions in callbacks

[Erlend E. Aasland]

Change by Erlend E. Aasland :


--
keywords: +patch
pull_requests: +27834
stage:  -> patch review
pull_request: https://github.com/python/cpython/pull/29591

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue45828] [sqlite3] use unraisable exceptions in callbacks

[Erlend E. Aasland]

Change by Erlend E. Aasland :


--
nosy: +serhiy.storchaka

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue45828] [sqlite3] use unraisable exceptions in callbacks

[Erlend E. Aasland]

New submission from Erlend E. Aasland :

In order to print tracebacks from exceptions in SQLite callbacks, the sqlite3 
extension module provides sqlite3.enable_callback_tracebacks(flag). Setting the 
flag to True instructs the sqlite3 extension module to PyErr_Print() if an 
exception occurs during a callback. Else, PyErr_Clear() is called.

>From the sqlite3.enable_callback_tracebacks() docs:

By default you will not get any tracebacks in user-defined functions,
aggregates, converters, authorizer callbacks etc. If you want to debug
them, you can call this function with flag set to True. Afterwards, you
will get tracebacks from callbacks on sys.stderr. Use False to disable the
feature again.


Few other exceptions use a similar approach:

$ grep -r PyErr_Print Modules 
Modules/_tkinter.c:PyErr_Print();
Modules/_testcapimodule.c:PyErr_Print();
Modules/main.c:PyErr_Print();
Modules/main.c:PyErr_Print();
Modules/main.c:PyErr_Print();
Modules/_io/bytesio.c:PyErr_Print();
Modules/_sqlite/connection.c:PyErr_Print();
Modules/_sqlite/cursor.c:PyErr_Print();
Modules/_xxtestfuzz/fuzzer.c:PyErr_Print();
Modules/_xxtestfuzz/fuzzer.c:PyErr_Print();
Modules/_xxtestfuzz/fuzzer.c:PyErr_Print();
Modules/_xxtestfuzz/fuzzer.c:PyErr_Print();
Modules/_xxtestfuzz/fuzzer.c:PyErr_Print();
Modules/_xxtestfuzz/fuzzer.c:PyErr_Print();
Modules/_xxtestfuzz/fuzzer.c:PyErr_Print();
Modules/_ctypes/callbacks.c:PyErr_Print();


We get a higher hit for unraisable exceptions:

$ grep -r PyErr_WriteUnraisable Modules | wc -l
  45


AFAICS, using unraisable exceptions is a better approach.


Current behaviour:

Python 3.10.0 (v3.10.0:b494f5935c, Oct  4 2021, 14:59:20) [Clang 12.0.5 
(clang-1205.0.22.11)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import sqlite3
>>> cx = sqlite3.connect(":memory:")
>>> cx.set_trace_callback(lambda stmt: 5/0)
>>> cx.execute("select 1")

>>> sqlite3.enable_callback_tracebacks(True)
>>> cx.execute("select 1")
Traceback (most recent call last):
  File "", line 1, in 
ZeroDivisionError: division by zero



With unraisable exceptions:

Python 3.11.0a2+ (heads/sqlite-unraisable-exceptions-dirty:de29590d6a, Nov 
17 2021, 10:29:19) [Clang 13.0.0 (clang-1300.0.29.3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import sqlite3
>>> cx = sqlite3.connect(":memory:")
>>> cx.set_trace_callback(lambda stmt: 5/0)
>>> cx.execute("select 1")

>>> sqlite3.enable_callback_tracebacks(True)
>>> cx.execute("select 1")
Exception ignored in:  at 0x10b4e3ee0>
Traceback (most recent call last):
  File "", line 1, in 
ZeroDivisionError: division by zero



The user experience is mostly unchanged; we get one extra line, telling us that 
the exception was ignored. Also, users can now use sys.unraisablehook:

>>> sys.unraisablehook = lambda unraisable: print(unraisable)
>>> cx.execute("select 1")
UnraisableHookArgs(exc_type=, 
exc_value=ZeroDivisionError('division by zero'), exc_traceback=, err_msg=None, object= at 0x10b4e3ee0>)



The only question I have, is if we should deprecate 
sqlite3.enable_callback_tracebacks() after switching to unraisable exceptions.

--
components: Extension Modules
messages: 406459
nosy: erlendaasland
priority: normal
severity: normal
status: open
title: [sqlite3] use unraisable exceptions in callbacks
versions: Python 3.11

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com