[Twisted-Python] Re: [Twisted-commits] r14614 - Describe log.debug, and 'printed' and 'debug' log dict items.
exarkun at divmod.com
Tue Oct 4 23:49:04 EDT 2005
On Tue, 4 Oct 2005 23:18:40 -0400, James Y Knight <foom at fuhm.net> wrote:
>On Oct 4, 2005, at 5:01 PM, glyph at divmod.com wrote:
>>On Tue, 4 Oct 2005 16:31:58 -0400, James Y Knight <foom at fuhm.net> wrote:
>>>log.msg("error message", isError=1)
>>Please don't ever do this. Log observers which check the isError flag
>>expect a stricter interface; a Failure object, for one thing, like log.err
>Actually they don't. They expect that the failure keyword may or may not be
>present. The only use of "levels" we have (DefaultObserver only showing
>error messages) filters out any non-isError messages, so there are
>circumstances in which you want to make sure you're emitting an isError=1
>>Really this should be using the interface keyword arg that itamar
>>mentioned, set to something like log.IErrorReport. To ensure portability
>>when that does become the convention, use log.err.
>But sometimes you cannot use log.err because you want to emit an error-
>level _message_, rather than the repr of an object, an exception, or a
>Notice how log.err("Foo!") doesn't actually do what you might hope.
>Contrast with log.msg("Foo!", isError=1) which does.
Neither of these is supported behavior. They're implementation accidents and shouldn't be used. It's understandable that this is surprising, since I doubt it's ever been written down anywhere.
More information about the Twisted-Python