Re: [log4perl-devel] requesting feedback on Log::Abstract
On Fri, 7 Sep 2007, Jonathan Swartz wrote: > I'd be interested in feedback on a proposed module, Log::Abstract, > described here: > > http://use.perl.org/~jonswar/journal/34366 > > This would be a tiny module designed to bridge CPAN modules that wish > to log (e.g. LWP, DBI, ...) with existing logging frameworks (e.g. > Log4perl), without the need for those modules to explicitly tie > themselves to a single framework. > > I'm a longtime log4perl fan/user, and Log::Abstract is my way of > increasing the input to log4perl in applications without resorting to > tricks such as infiltrate_lwp(). :) Hi Jonathan, you're addressing something really important here. It is really unfortunate that important CPAN modules like LWP or Rose::DB don't have usable logging mechanisms in place. Once you're used to category-based logging it's hard to go back to these home-grown and less convenient solutions. I think it's a great idea to promote standardized logging on CPAN and letting the user choose the actual implementation will definitely help to make strides towards that goal. By the way, I don't agree that "For small modules that want to minimize dependencies, depending on Log4perl (for example) is a non-starter." The Log4perl core doesn't have dependencies other than perl's core modules. One thing missing from your proposal is Log4perl's :easy mode. If you think about it, getting a logger and calling its method is a lot of typing, given that you just want to log something. That's why in Log4perl you can use DEBUG "Log this!"; and you're done. No getting a logger, no method calling, no category passing. It's all automatic. Behind the scenes, it gets a 'stealth logger' with the category set to the current package and calls the appropriate logging method on it. This feature is huge. I'm using it almost exclusively in everything I write. Any chance of adding that? Keep up the great work! -- Mike Mike Schilli [EMAIL PROTECTED] - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ log4perl-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/log4perl-devel
Re: [log4perl-devel] requesting feedback on Log::Abstract
> > On Sep 8, 2007, at 1:19 PM, Mike Schilli wrote: > > > On Fri, 7 Sep 2007, Jonathan Swartz wrote: > > > > I'd be interested in feedback on a proposed module, Log::Abstract, > > described here: > > > > http://use.perl.org/~jonswar/journal/34366 > > ... > > By the way, I don't agree that "For small modules that want to > minimize dependencies, depending on Log4perl (for example) is a > non-starter." The Log4perl core doesn't have dependencies other > than perl's core modules. Fair enough. > > One thing missing from your proposal is Log4perl's :easy mode > [sourceforge.net]. If you think about it, getting a logger and > calling its method is a lot of typing, given that you just want > to log something. That's why in Log4perl you can use > > DEBUG "Log this!"; > > and you're done. No getting a logger, no method calling, no > category passing. It's all automatic. Behind the scenes, it gets > a 'stealth logger' with the category set to the current package > and calls the appropriate logging method on it. This feature is > huge. I'm using it almost exclusively in everything I write. > > Any chance of adding that? Did you see this in the posting? As a convenient shorthand, you can use package Foo; use Log::Abstract qw($log); to create the logger, which is equivalent to the first example except that $log is (necessarily) a package-scoped rather than lexical variable. So this creates a logger for you with the category set to the current package, similar to easy mode. The syntax is pretty minimal. The problem I have with the DEBUG etc keywords is that they promote inefficient behavior. e.g. DEBUG "Current arguments: " . Dumper([EMAIL PROTECTED]); will take the performance hit for Dumper() even when debug logging isn't turned on. This may be fine for a particular application where performance is not an issue, but I would never want to encourage any CPAN module author to do this. In fact, in this thread on perl.module-authors, http://groups.google.com/group/perl.module-authors/msg/ cbd5a168d5d780a8?hl=en& it was suggested that even the usual "fast" $log->is_debug() check is too much of a hit. So I proposed we export a live $log_is_debug variable that would change dynamically to reflect the current level. I suppose one could combine the syntaxes: DEBUG "Current arguments: " . Dumper([EMAIL PROTECTED]) if $log_is_debug; but at this point you are only saving 6 characters or so. > > One thing to watch out for is performance. People don't want > their applications to slow down just because a module has a > logging capability. Exactly my point above. :) Thanks for your positive feedback! I will definitely need to have the support of major logging frameworks such as log4perl for this module to be a success. Best, Jon - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ log4perl-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/log4perl-devel
Re: [log4perl-devel] requesting feedback on Log::Abstract
On Sat, 8 Sep 2007, Jonathan Swartz wrote:
> Did you see this in the posting?
>
> As a convenient shorthand, you can use
>
> package Foo;
> use Log::Abstract qw($log);
>
> to create the logger, which is equivalent to the first example
> except that $log is
> (necessarily) a package-scoped rather than lexical variable.
>
> So this creates a logger for you with the category set to the current
> package, similar to easy mode. The syntax is pretty minimal.
Ah, gotcha. So you would call
$log->debug(...)
instead of
DEBUG "..."
which is probably acceptable in terms of additional key strokes
(although it might throw off novices).
> The problem I have with the DEBUG etc keywords is that they promote
>inefficient behavior. e.g.
>
> DEBUG "Current arguments: " . Dumper([EMAIL PROTECTED]);
>
> will take the performance hit for Dumper() even when debug logging
> isn't turned on.
Sure, although I don't see how
$log->debug("Current arguments: " . Dumper([EMAIL PROTECTED]));
is any different. By the way, in Log4perl you can pass a subroutine ref
to the method, which eliminates the problem:
DEBUG sub { "Current arguments: " . Dumper([EMAIL PROTECTED]) };
Efficient, but ugly :).
While you're at it, here's my pipe dream: I want something like Dtrace,
where the logging framework zeroes out the opcodes that are currently
inactive, and the interpreter rushes through them at light speed with
practically no overhead.
-- Mike
Mike Schilli
[EMAIL PROTECTED]
-
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2005.
http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/
___
log4perl-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/log4perl-devel
