[ViewVC] Diff of: cvs/AnyEvent/lib/AnyEvent/Log.pm

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.8 by root, Fri Aug 19 19:20:36 2011 UTC vs.
Revision 1.11 by root, Sat Aug 20 01:03:09 2011 UTC

…		…
10	AE::log debug => "hit my knee";	10	AE::log debug => "hit my knee";
11	AE::log warn => "it's a bit too hot";	11	AE::log warn => "it's a bit too hot";
12	AE::log error => "the flag was false!";	12	AE::log error => "the flag was false!";
13	AE::log fatal => "the bit toggled! run!";	13	AE::log fatal => "the bit toggled! run!";
14		14
15	# complex use	15	# "complex" use
16	use AnyEvent::Log;	16	use AnyEvent::Log;
17		17
18	my $tracer = AnyEvent::Log::logger trace => \$my $trace;	18	my $tracer = AnyEvent::Log::logger trace => \$my $trace;
19		19
20	$tracer->("i am here") if $trace;	20	$tracer->("i am here") if $trace;
21	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;	21	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;
22		22
23	#TODO: config	23	# configuration
24	#TODO: ctx () becomes caller[0]...	24
		25	# set logging for this package to maximum
		26	AnyEvent::Log::ctx->level ("all");
		27
		28	# set logging globally to anything below debug
		29	(AnyEvent::Log::ctx "")->level ("notice");
		30
		31	# see also EXAMPLES, below
		32
		33	# disable logging for package "AnyEvent" and all packages below it
		34	AnyEvent->AnyEvent::Log::ctx->level (0);
		35
		36	# log everything below debug to a file, for the whole program
		37	my $ctx = AnyEvent::Log::ctx;
		38	$ctx->log_cb (sub { print FILE shift; 0 });
		39	(AnyEvent::Log::ctx "")->add ($ctx);
25		40
26	=head1 DESCRIPTION	41	=head1 DESCRIPTION
27		42
28	This module implements a relatively simple "logging framework". It doesn't	43	This module implements a relatively simple "logging framework". It doesn't
29	attempt to be "the" logging solution or even "a" logging solution for	44	attempt to be "the" logging solution or even "a" logging solution for
30	AnyEvent - AnyEvent simply creates logging messages internally, and this	45	AnyEvent - AnyEvent simply creates logging messages internally, and this
31	module more or less exposes the mechanism, with some extra spiff to allow	46	module more or less exposes the mechanism, with some extra spiff to allow
32	using it from other modules as well.	47	using it from other modules as well.
33		48
34	Remember that the default verbosity level is C<0>, so nothing will be	49	Remember that the default verbosity level is C<0>, so nothing will be
35	logged, ever, unless you set C<PERL_ANYEVENT_VERBOSE> to a higher number	50	logged, unless you set C<PERL_ANYEVENT_VERBOSE> to a higher number before
36	before starting your program.#TODO	51	starting your program, or change the logging level at runtime with
		52	something like:
37		53
38	Possible future extensions are to allow custom log targets (where the	54	use AnyEvent;
39	level is an object), log filtering based on package, formatting, aliasing	55	(AnyEvent::Log::ctx "")->level ("info");
40	or package groups.
41		56
		57	The design goal behind this module was to keep it simple (and small),
		58	but make it powerful enough to be potentially useful for any module, and
		59	extensive enough for the most common tasks, such as logging to multiple
		60	targets, or being able to log into a database.
		61
42	=head1 LOG FUNCTIONS	62	=head1 LOGGING FUNCTIONS
43		63
44	These functions allow you to log messages. They always use the caller's	64	These functions allow you to log messages. They always use the caller's
45	package as a "logging module/source". Also, the main logging function is	65	package as a "logging module/source". Also, the main logging function is
46	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is	66	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is
47	loaded.	67	loaded.
…		…
71	"$now_str1$f$now_str2"	91	"$now_str1$f$now_str2"
72	}	92	}
73		93
74	our %CTX; # all logging contexts	94	our %CTX; # all logging contexts
75		95
76	my $default_log_cb = sub { 0 };
77
78	# creates a default package context object for the given package	96	# creates a default package context object for the given package
79	sub _pkg_ctx($) {	97	sub _pkg_ctx($) {
80	my $ctx = bless [$_[0], 0, {}, $default_log_cb], "AnyEvent::Log::Ctx";	98	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";
81		99
82	# link "parent" package	100	# link "parent" package
83	my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "";	101	my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "AE::Log::Top";
84		102
85	$pkg = $CTX{$pkg} \|\|= &_pkg_ctx ($pkg);	103	$pkg = $CTX{$pkg} \|\|= &_pkg_ctx ($pkg);
86	$ctx->[2]{$pkg+0} = $pkg;	104	$ctx->[2]{$pkg+0} = $pkg;
87		105
88	$ctx	106	$ctx
…		…
114	Note that you can (and should) call this function as C<AnyEvent::log> or	132	Note that you can (and should) call this function as C<AnyEvent::log> or
115	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't	133	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't
116	need any additional functionality), as those functions will load the	134	need any additional functionality), as those functions will load the
117	logging module on demand only. They are also much shorter to write.	135	logging module on demand only. They are also much shorter to write.
118		136
119	Also, if you otpionally generate a lot of debug messages (such as when	137	Also, if you optionally generate a lot of debug messages (such as when
120	tracing some code), you should look into using a logger callback and a	138	tracing some code), you should look into using a logger callback and a
121	boolean enabler (see C<logger>, below).	139	boolean enabler (see C<logger>, below).
122		140
123	Example: log something at error level.	141	Example: log something at error level.
124		142
…		…
146	debug => 8,	164	debug => 8,
147	trace => 9,	165	trace => 9,
148	);	166	);
149		167
150	sub now () { time }	168	sub now () { time }
		169
151	AnyEvent::post_detect {	170	AnyEvent::post_detect {
152	*now = \&AE::now;	171	*now = \&AE::now;
153	};	172	};
154		173
155	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);	174	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);
156		175
157	# time, ctx, level, msg	176	# time, ctx, level, msg
158	sub _format($$$$) {	177	sub _format($$$$) {
159	my $pfx = ft $_[0];	178	my $ts = ft $_[0];
		179	my $ct = " ";
160		180
161	join "",	181	my @res;
162	map "$pfx $_\n",	182
163	split /\n/,
164	sprintf "%-5s %s: %s", $LEVEL2STR[$_[2]], $_[1][0], $_[3]	183	for (split /\n/, sprintf "%-5s %s: %s", $LEVEL2STR[$_[2]], $_[1][0], $_[3]) {
		184	push @res, "$ts$ct$_\n";
		185	$ct = " + ";
		186	}
		187
		188	join "", @res
165	}	189	}
166		190
167	sub _log {	191	sub _log {
168	my ($ctx, $level, $format, @args) = @_;	192	my ($ctx, $level, $format, @args) = @_;
169		193
		194	$level = $level > 0 && $level <= 9
		195	? $level+0
170	$level = $level > 0 && $level <= 9 ? $level+0 : $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";	196	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";
171		197
172	my $mask = 1 << $level;	198	my $mask = 1 << $level;
173	my $now = AE::now;
174		199
175	my (@ctx, $did_format, $fmt);	200	my (%seen, @ctx, $now, $fmt);
176		201
177	do {	202	do
178	if ($ctx->[1] & $mask) {	203	{
		204	# skip if masked
		205	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {
		206	if ($ctx->[3]) {
179	# logging target found	207	# logging target found
180		208
181	# get raw message	209	# now get raw message, unless we have it already
182	unless ($did_format) {	210	unless ($now) {
183	$format = $format->() if ref $format;	211	$format = $format->() if ref $format;
184	$format = sprintf $format, @args if @args;	212	$format = sprintf $format, @args if @args;
185	$format =~ s/\n$//;	213	$format =~ s/\n$//;
186	$did_format = 1;	214	$now = AE::now;
187	};	215	};
188		216
189	# format msg	217	# format msg
190	my $str = $ctx->[4]	218	my $str = $ctx->[4]
191	? $ctx->[4]($now, $_[0], $level, $format)	219	? $ctx->[4]($now, $_[0], $level, $format)
192	: $fmt \|\|= _format $now, $_[0], $level, $format;	220	: $fmt \|\|= _format $now, $_[0], $level, $format;
193		221
194	$ctx->[3]($str)	222	$ctx->[3]($str);
195	and next;	223	}
		224
		225	# not masked, not consumed - propagate to parent contexts
		226	push @ctx, values %{ $ctx->[2] };
		227	}
196	}	228	}
197
198	# not consume - push parent contexts
199	push @ctx, values %{ $ctx->[2] };
200	} while $ctx = pop @ctx;	229	while $ctx = pop @ctx;
201		230
202	exit 1 if $level <= 1;	231	exit 1 if $level <= 1;
203	}	232	}
204		233
205	sub log($$;@) {	234	sub log($$;@) {
…		…
258	# re-assess logging status for all loggers	287	# re-assess logging status for all loggers
259	sub _reassess {	288	sub _reassess {
260	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {	289	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {
261	my ($ctx, $level, $renabled) = @$_;	290	my ($ctx, $level, $renabled) = @$_;
262		291
263	# to detetc whether a message would be logged, we # actually	292	# to detect whether a message would be logged, we # actually
264	# try to log one and die. this isn't # fast, but we can be	293	# try to log one and die. this isn't fast, but we can be
265	# sure that the logging decision is correct :)	294	# sure that the logging decision is correct :)
266		295
267	$$renabled = !eval {	296	$$renabled = !eval {
268	local $SIG{__DIE__};	297	local $SIG{__DIE__};
269		298
…		…
306	_logger	335	_logger
307	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	336	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
308	@_	337	@_
309	}	338	}
310		339
311	#TODO
312
313	=back	340	=back
314		341
315	=head1 CONFIGURATION FUNCTIONALITY	342	=head1 LOGGING CONTEXTS
316		343
317	None, yet, except for C<PERL_ANYEVENT_VERBOSE>, described in the L<AnyEvent> manpage.	344	This module associates every log message with a so-called I<logging
		345	context>, based on the package of the caller. Every perl package has its
		346	own logging context.
318		347
319	#TODO: wahst a context	348	A logging context has three major responsibilities: filtering, logging and
320	#TODO	349	propagating the message.
		350
		351	For the first purpose, filtering, each context has a set of logging
		352	levels, called the log level mask. Messages not in the set will be ignored
		353	by this context (masked).
		354
		355	For logging, the context stores a formatting callback (which takes the
		356	timestamp, context, level and string message and formats it in the way
		357	it should be logged) and a logging callback (which is responsible for
		358	actually logging the formatted message and telling C<AnyEvent::Log>
		359	whether it has consumed the message, or whether it should be propagated).
		360
		361	For propagation, a context can have any number of attached I<parent
		362	contexts>. Any message that is neither masked by the logging mask nor
		363	masked by the logging callback returning true will be passed to all parent
		364	contexts.
		365
		366	Each call to a logging function will log the message at most once per
		367	context, so it does not matter (much) if there are cycles or if the
		368	message can arrive at the same context via multiple paths.
		369
		370	=head2 DEFAULTS
		371
		372	By default, all logging contexts have an full set of log levels ("all"), a
		373	disabled logging callback and the default formatting callback.
		374
		375	Package contexts have the package name as logging title by default.
		376
		377	They have exactly one parent - the context of the "parent" package. The
		378	parent package is simply defined to be the package name without the last
		379	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
		380	and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the
		381	exception of the rule - just like the parent of any package name in
		382	Perl is C<main>, the default parent of any toplevel package context is
		383	C<AnyEvent::Log::Top>.
		384
		385	Since perl packages form only an approximate hierarchy, this parent
		386	context can of course be removed.
		387
		388	All other (anonymous) contexts have no parents and an empty title by
		389	default.
		390
		391	When the module is loaded it creates the default context called
		392	C<AnyEvent::Log::Default>, which simply logs everything to STDERR and
		393	doesn't propagate anything anywhere by default. The purpose of the default
		394	context is to provide a convenient place to override the global logging
		395	target or to attach additional log targets. It's not meant for filtering.
		396
		397	It then creates the root context called C<AnyEvent::Log::Root> and
		398	sets its log level set to all levels up to the one specified by
		399	C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the default logging
		400	context to it. The purpose of the root context is to simply provide
		401	filtering according to some global log level.
		402
		403	Finally it creates the toplevel package context called
		404	C<AnyEvent::Log::Top> and attached the root context but otherwise leaves
		405	it at default config. It's purpose is simply to collect all log messages
		406	system-wide.
		407
		408	These three special contexts can also be referred to by the names
		409	C<AE::Log::Default>, C<AE::Log::Root> and C<AE::Log::Top>.
		410
		411	The effect of all this is that log messages, by default, wander up
		412	to the root context where log messages with lower priority then
		413	C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered away and then to the
		414	AnyEvent::Log::Default context to be logged to STDERR.
		415
		416	Splitting the top level context into three contexts makes it easy to set
		417	a global logging level (by modifying the root context), but still allow
		418	other contexts to log, for example, their debug and trace messages to the
		419	default target despite the global logging level, or to attach additional
		420	log targets that log messages, regardless of the global logging level.
		421
		422	It also makes it easy to replace the default STDERR-logger by something
		423	that logs to a file, or to attach additional logging targets.
		424
		425	=head2 CREATING/FINDING/DESTROYING CONTEXTS
321		426
322	=over 4	427	=over 4
323		428
324	=item $ctx = AnyEvent::Log::ctx [$pkg]	429	=item $ctx = AnyEvent::Log::ctx [$pkg]
325		430
326	Returns a I<config> object for the given package name.	431	This function creates or returns a logging context (which is an object).
327		432
328	If no package name is given, returns the context for the current perl	433	If a package name is given, then the context for that packlage is
		434	returned. If it is called without any arguments, then the context for the
329	package (i.e. the same context as a C<AE::log> call would use).	435	callers package is returned (i.e. the same context as a C<AE::log> call
		436	would use).
330		437
331	If C<undef> is given, then it creates a new anonymous context that is not	438	If C<undef> is given, then it creates a new anonymous context that is not
332	tied to any package and is destroyed when no longer referenced.	439	tied to any package and is destroyed when no longer referenced.
333		440
334	=cut	441	=cut
…		…
338		445
339	ref $pkg	446	ref $pkg
340	? $pkg	447	? $pkg
341	: defined $pkg	448	: defined $pkg
342	? $CTX{$pkg} \|\|= AnyEvent::Log::_pkg_ctx $pkg	449	? $CTX{$pkg} \|\|= AnyEvent::Log::_pkg_ctx $pkg
343	: bless [undef, 0, undef, $default_log_cb], "AnyEvent::Log::Ctx"	450	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"
344	}	451	}
345		452
346	# create default root context	453	=item AnyEvent::Log::reset
347	{	454
		455	Deletes all contexts and recreates the default hierarchy, i.e. resets the
		456	logging subsystem to defaults.
		457
		458	This can be used to implement config-file (re-)loading: before loading a
		459	configuration, reset all contexts.
		460
		461	=cut
		462
		463	sub reset {
		464	@$_ = () for values %CTX; # just to be sure - to kill circular logging dependencies
		465	%CTX = ();
		466
348	my $root = ctx undef;	467	my $default = ctx undef;
349	$root->[0] = "";	468	$default->title ("AnyEvent::Log::Default");
350	$root->title ("default");
351	$root->level ($AnyEvent::VERBOSE);
352	$root->log_cb (sub {	469	$default->log_cb (sub {
353	print STDERR shift;	470	print STDERR shift;
354	0	471	0
355	});	472	});
356	$CTX{""} = $root;	473	$CTX{"AnyEvent::Log::Default"} = $CTX{"AE::Log::Default"} = $default;
		474
		475	my $root = ctx undef;
		476	$root->title ("AnyEvent::Log::Root");
		477	$root->level ($AnyEvent::VERBOSE);
		478	$root->attach ($default);
		479	$CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $root;
		480
		481	my $top = ctx undef;
		482	$top->title ("AnyEvent::Log::Top");
		483	$top->attach ($root);
		484	$CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $top;
357	}	485	}
		486
		487	AnyEvent::Log::reset;
		488
		489	package AnyEvent::Log::Default;
		490	package AE::Log::Default;
		491	package AnyEvent::Log::Root;
		492	package AE::Log::Root;
		493	package AnyEvent::Log::Top;
		494	package AE::Log::Top;
		495
		496	=back
		497
		498	=cut
358		499
359	package AnyEvent::Log::Ctx;	500	package AnyEvent::Log::Ctx;
360		501
361	# 0 1 2 3 4	502	# 0 1 2 3 4
362	# [$title, $level, %$parents, &$logcb, &$fmtcb]	503	# [$title, $level, %$parents, &$logcb, &$fmtcb]
		504
		505	=head2 CONFIGURING A LOG CONTEXT
		506
		507	The following methods can be used to configure the logging context.
		508
		509	=over 4
363		510
364	=item $ctx->title ([$new_title])	511	=item $ctx->title ([$new_title])
365		512
366	Returns the title of the logging context - this is the package name, for	513	Returns the title of the logging context - this is the package name, for
367	package contexts, and a user defined string for all others.	514	package contexts, and a user defined string for all others.
…		…
373	sub title {	520	sub title {
374	$_[0][0] = $_[1] if @_ > 1;	521	$_[0][0] = $_[1] if @_ > 1;
375	$_[0][0]	522	$_[0][0]
376	}	523	}
377		524
		525	=back
		526
		527	=head3 LOGGING LEVELS
		528
		529	The following methods deal with the logging level set associated with the
		530	log context.
		531
		532	The most common method to use is probably C<< $ctx->level ($level) >>,
		533	which configures the specified and any higher priority levels.
		534
		535	All functions which accept a list of levels also accept the special string
		536	C<all> which expands to all logging levels.
		537
		538	=over 4
		539
378	=item $ctx->levels ($level[, $level...)	540	=item $ctx->levels ($level[, $level...)
379		541
380	Enables logging fot the given levels and disables it for all others.	542	Enables logging for the given levels and disables it for all others.
381		543
382	=item $ctx->level ($level)	544	=item $ctx->level ($level)
383		545
384	Enables logging for the given level and all lower level (higher priority)	546	Enables logging for the given level and all lower level (higher priority)
385	ones. Specifying a level of C<0> or C<off> disables all logging for this	547	ones. In addition to normal logging levels, specifying a level of C<0> or
386	level.	548	C<off> disables all logging for this level.
387		549
388	Example: log warnings, errors and higher priority messages.	550	Example: log warnings, errors and higher priority messages.
389		551
390	$ctx->level ("warn");	552	$ctx->level ("warn");
391	$ctx->level (5); # same thing, just numeric	553	$ctx->level (5); # same thing, just numeric
…		…
399	Disables logging for the given levels, leaving all others unchanged.	561	Disables logging for the given levels, leaving all others unchanged.
400		562
401	=cut	563	=cut
402		564
403	sub _lvl_lst {	565	sub _lvl_lst {
		566	map {
		567	$_ > 0 && $_ <= 9 ? $_+0
		568	: $_ eq "all" ? (1 .. 9)
404	map { $_ > 0 && $_ <= 9 ? $_+0 : $STR2LEVEL{$_} \|\| Carp::croak "$_: not a valid logging level, caught" }	569	: $STR2LEVEL{$_} \|\| Carp::croak "$_: not a valid logging level, caught"
405	@_	570	} @_
406	}	571	}
407		572
408	our $NOP_CB = sub { 0 };	573	our $NOP_CB = sub { 0 };
409		574
410	sub levels {	575	sub levels {
…		…
415	AnyEvent::Log::_reassess;	580	AnyEvent::Log::_reassess;
416	}	581	}
417		582
418	sub level {	583	sub level {
419	my $ctx = shift;	584	my $ctx = shift;
420	my $lvl = $_[0] =~ /^(?:0\|off\|none)$/ ? 0 : (_lvl_lst $_[0])[0];	585	my $lvl = $_[0] =~ /^(?:0\|off\|none)$/ ? 0 : (_lvl_lst $_[0])[-1];
		586
421	$ctx->[1] = ((1 << $lvl) - 1) << 1;	587	$ctx->[1] = ((1 << $lvl) - 1) << 1;
422	AnyEvent::Log::_reassess;	588	AnyEvent::Log::_reassess;
423	}	589	}
424		590
425	sub enable {	591	sub enable {
…		…
434	$ctx->[1] &= ~(1 << $_)	600	$ctx->[1] &= ~(1 << $_)
435	for &_lvl_lst;	601	for &_lvl_lst;
436	AnyEvent::Log::_reassess;	602	AnyEvent::Log::_reassess;
437	}	603	}
438		604
		605	=back
		606
		607	=head3 PARENT CONTEXTS
		608
		609	The following methods attach and detach another logging context to a
		610	logging context.
		611
		612	Log messages are propagated to all parent contexts, unless the logging
		613	callback consumes the message.
		614
		615	=over 4
		616
439	=item $ctx->attach ($ctx2[, $ctx3...])	617	=item $ctx->attach ($ctx2[, $ctx3...])
440		618
441	Attaches the given contexts as parents to this context. It is not an error	619	Attaches the given contexts as parents to this context. It is not an error
442	to add a context twice (the second add will be ignored).	620	to add a context twice (the second add will be ignored).
443		621
…		…
448	Removes the given parents from this context - it's not an error to attempt	626	Removes the given parents from this context - it's not an error to attempt
449	to remove a context that hasn't been added.	627	to remove a context that hasn't been added.
450		628
451	A context can be specified either as package name or as a context object.	629	A context can be specified either as package name or as a context object.
452		630
		631	=item $ctx->parents ($ctx2[, $ctx3...])
		632
		633	Replaces all parents attached to this context by the ones given.
		634
453	=cut	635	=cut
454		636
455	sub attach {	637	sub attach {
456	my $ctx = shift;	638	my $ctx = shift;
457		639
…		…
463	my $ctx = shift;	645	my $ctx = shift;
464		646
465	delete $ctx->[2]{$_+0}	647	delete $ctx->[2]{$_+0}
466	for map { AnyEvent::Log::ctx $_ } @_;	648	for map { AnyEvent::Log::ctx $_ } @_;
467	}	649	}
		650
		651	sub parents {
		652	undef $_[0][2];
		653	&attach;
		654	}
		655
		656	=back
		657
		658	=head3 MESSAGE LOGGING
		659
		660	The following methods configure how the logging context actually does
		661	the logging (which consists of formatting the message and printing it or
		662	whatever it wants to do with it) and also allows you to log messages
		663	directly to a context, without going via your package context.
		664
		665	=over 4
468		666
469	=item $ctx->log_cb ($cb->($str))	667	=item $ctx->log_cb ($cb->($str))
470		668
471	Replaces the logging callback on the context (C<undef> disables the	669	Replaces the logging callback on the context (C<undef> disables the
472	logging callback).	670	logging callback).
…		…
482	Example: a very simple logging callback, simply dump the message to STDOUT	680	Example: a very simple logging callback, simply dump the message to STDOUT
483	and do not consume it.	681	and do not consume it.
484		682
485	$ctx->log_cb (sub { print STDERR shift; 0 });	683	$ctx->log_cb (sub { print STDERR shift; 0 });
486		684
		685	You can filter messages by having a log callback that simply returns C<1>
		686	and does not do anything with the message, but this counts as "message
		687	being logged" and might not be very efficient.
		688
		689	Example: propagate all messages except for log levels "debug" and
		690	"trace". The messages will still be generated, though, which can slow down
		691	your program.
		692
		693	$ctx->levels ("debug", "trace");
		694	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages
		695
487	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	696	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))
488		697
489	Replaces the fornatting callback on the cobntext (C<undef> restores the	698	Replaces the formatting callback on the context (C<undef> restores the
490	default formatter).	699	default formatter).
491		700
492	The callback is passed the (possibly fractional) timestamp, the original	701	The callback is passed the (possibly fractional) timestamp, the original
493	logging context, the (numeric) logging level and the raw message string and needs to	702	logging context, the (numeric) logging level and the raw message string and needs to
494	return a formatted log message. In most cases this will be a string, but	703	return a formatted log message. In most cases this will be a string, but
…		…
522	=cut	731	=cut
523		732
524	sub log_cb {	733	sub log_cb {
525	my ($ctx, $cb) = @_;	734	my ($ctx, $cb) = @_;
526		735
527	$ctx->[3] = $cb \|\| $default_log_cb;	736	$ctx->[3] = $cb;
528	}	737	}
529		738
530	sub fmt_cb {	739	sub fmt_cb {
531	my ($ctx, $cb) = @_;	740	my ($ctx, $cb) = @_;
532		741

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents): Revision 1.8 by root, Fri Aug 19 19:20:36 2011 UTC vs. Revision 1.11 by root, Sat Aug 20 01:03:09 2011 UTC

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.8 by root, Fri Aug 19 19:20:36 2011 UTC vs.
Revision 1.11 by root, Sat Aug 20 01:03:09 2011 UTC