[Python-Dev] Using logging in the stdlib and its unit tests

[Georg Brandl]

Am 08.12.2010 01:09, schrieb Antoine Pitrou:
> On Tue, 7 Dec 2010 23:45:39 +0000 (UTC)
> Vinay Sajip <vinay_sajip at yahoo.co.uk> wrote:
>> Antoine Pitrou <solipsis <at> pitrou.net> writes:
>> 
>> > 
>> > I thought "error" and "critical" messages were logged to stderr by
>> > default? Isn't it the case?
>> > 
>> 
>> Only if you call basicConfig() or use the logging.debug(), logging.info(), etc.
>> module-level convenience functions (which call basicConfig under the hood).
> 
> Why wouldn't it be the default for all logging calls ? Such special
> cases don't really make things easy to remember.
> 
>> When is the NullHandler needed? Only for cases where an application developer
>> uses a library which does logging under the covers (for those users who might be
>> interested in logging its operations), but where that application developer
>> doesn't use logging themselves for that application.
> 
> You seem pretty tied up to the "application developer" situation. There
> are cases (scripts, prototyping, etc.) where you certainly want to see
> error messages (errors should not pass silently) but don't want to
> configure logging for each of the libraries you use.

But errors don't pass silently, do they?  The usual way to present errors
is still by raising exceptions.

Georg