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

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.13 by root, Sat Aug 20 01:34:12 2011 UTC vs.
Revision 1.36 by root, Thu Aug 25 05:39:47 2011 UTC

…		…
2		2
3	AnyEvent::Log - simple logging "framework"	3	AnyEvent::Log - simple logging "framework"
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	# simple use	7	Simple uses:
		8
8	use AnyEvent;	9	use AnyEvent;
9		10
10	AE::log debug => "hit my knee";	11	AE::log debug => "hit my knee";
11	AE::log warn => "it's a bit too hot";	12	AE::log warn => "it's a bit too hot";
12	AE::log error => "the flag was false!";	13	AE::log error => "the flag was false!";
13	AE::log fatal => "the bit toggled! run!";	14	AE::log fatal => "the bit toggled! run!"; # never returns
14		15
15	# "complex" use	16	"Complex" uses (for speed sensitive code):
		17
16	use AnyEvent::Log;	18	use AnyEvent::Log;
17		19
18	my $tracer = AnyEvent::Log::logger trace => \$my $trace;	20	my $tracer = AnyEvent::Log::logger trace => \$my $trace;
19		21
20	$tracer->("i am here") if $trace;	22	$tracer->("i am here") if $trace;
21	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;	23	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;
22		24
23	# configuration	25	Configuration (also look at the EXAMPLES section):
24		26
25	# set logging for this package to maximum	27	# set logging for the current package to errors and higher only
26	AnyEvent::Log::ctx->level ("all");	28	AnyEvent::Log::ctx->level ("error");
27		29
28	# set logging globally to anything below debug	30	# set logging level to suppress anything below "notice"
29	(AnyEvent::Log::ctx "")->level ("notice");	31	$AnyEvent::Log::FILTER->level ("notice");
30		32
31	# see also EXAMPLES, below	33	# send all critical and higher priority messages to syslog,
32		34	# regardless of (most) other settings
33	# disable logging for package "AnyEvent" and all packages below it	35	$AnyEvent::Log::COLLECT->attach (new AnyEvent::Log::Ctx
34	AnyEvent->AnyEvent::Log::ctx->level (0);	36	level => "critical",
35		37	log_to_syslog => 0,
36	# log everything below debug to a file, for the whole program	38	);
37	my $ctx = AnyEvent::Log::ctx;
38	$ctx->log_cb (sub { print FILE shift; 0 });
39	(AnyEvent::Log::ctx "")->add ($ctx);
40		39
41	=head1 DESCRIPTION	40	=head1 DESCRIPTION
42		41
43	This module implements a relatively simple "logging framework". It doesn't	42	This module implements a relatively simple "logging framework". It doesn't
44	attempt to be "the" logging solution or even "a" logging solution for	43	attempt to be "the" logging solution or even "a" logging solution for
45	AnyEvent - AnyEvent simply creates logging messages internally, and this	44	AnyEvent - AnyEvent simply creates logging messages internally, and this
46	module more or less exposes the mechanism, with some extra spiff to allow	45	module more or less exposes the mechanism, with some extra spiff to allow
47	using it from other modules as well.	46	using it from other modules as well.
48		47
49	Remember that the default verbosity level is C<0>, so nothing will be	48	Remember that the default verbosity level is C<0> (C<off>), so nothing
50	logged, unless you set C<PERL_ANYEVENT_VERBOSE> to a higher number before	49	will be logged, unless you set C<PERL_ANYEVENT_VERBOSE> to a higher number
51	starting your program, or change the logging level at runtime with	50	before starting your program, or change the logging level at runtime with
52	something like:	51	something like:
53		52
54	use AnyEvent;	53	use AnyEvent::Log;
55	(AnyEvent::Log::ctx "")->level ("info");	54	$AnyEvent::Log::FILTER->level ("info");
56		55
57	The design goal behind this module was to keep it simple (and small),	56	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	57	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	58	extensive enough for the most common tasks, such as logging to multiple
60	targets, or being able to log into a database.	59	targets, or being able to log into a database.
61		60
		61	The module is also usable before AnyEvent itself is initialised, in which
		62	case some of the functionality might be reduced.
		63
		64	The amount of documentation might indicate otherwise, but the runtime part
		65	of the module is still just below 300 lines of code.
		66
		67	=head1 LOGGING LEVELS
		68
		69	Logging levels in this module range from C<1> (highest priority) to C<9>
		70	(lowest priority). Note that the lowest numerical value is the highest
		71	priority, so when this document says "higher priority" it means "lower
		72	numerical value".
		73
		74	Instead of specifying levels by name you can also specify them by aliases:
		75
		76	LVL NAME SYSLOG PERL NOTE
		77	1 fatal emerg exit aborts program!
		78	2 alert
		79	3 critical crit
		80	4 error err die
		81	5 warn warning
		82	6 note notice
		83	7 info
		84	8 debug
		85	9 trace
		86
		87	As you can see, some logging levels have multiple aliases - the first one
		88	is the "official" name, the second one the "syslog" name (if it differs)
		89	and the third one the "perl" name, suggesting that you log C<die> messages
		90	at C<error> priority.
		91
		92	You can normally only log a single message at highest priority level
		93	(C<1>, C<fatal>), because logging a fatal message will also quit the
		94	program - so use it sparingly :)
		95
		96	Some methods also offer some extra levels, such as C<0>, C<off>, C<none>
		97	or C<all> - these are only valid in the methods they are documented for.
		98
62	=head1 LOGGING FUNCTIONS	99	=head1 LOGGING FUNCTIONS
63		100
64	These functions allow you to log messages. They always use the caller's	101	These functions allow you to log messages. They always use the caller's
65	package as a "logging module/source". Also, the main logging function is	102	package as a "logging context". Also, the main logging function C<log> is
66	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is	103	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is
67	loaded.	104	loaded.
68		105
69	=over 4	106	=over 4
70		107
…		…
75	use Carp ();	112	use Carp ();
76	use POSIX ();	113	use POSIX ();
77		114
78	use AnyEvent (); BEGIN { AnyEvent::common_sense }	115	use AnyEvent (); BEGIN { AnyEvent::common_sense }
79	use AnyEvent::Util ();	116	use AnyEvent::Util ();
		117
		118	our $VERSION = $AnyEvent::VERSION;
		119
		120	our ($COLLECT, $FILTER, $LOG);
80		121
81	our ($now_int, $now_str1, $now_str2);	122	our ($now_int, $now_str1, $now_str2);
82		123
83	# Format Time, not public - yet?	124	# Format Time, not public - yet?
84	sub ft($) {	125	sub ft($) {
…		…
89	if $now_int != $i;	130	if $now_int != $i;
90		131
91	"$now_str1$f$now_str2"	132	"$now_str1$f$now_str2"
92	}	133	}
93		134
94	our %CTX; # all logging contexts	135	our %CTX; # all package contexts
95		136
96	# creates a default package context object for the given package	137	# creates a default package context object for the given package
97	sub _pkg_ctx($) {	138	sub _pkg_ctx($) {
98	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";	139	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";
99		140
100	# link "parent" package	141	# link "parent" package
101	my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "AE::Log::Top";	142	my $parent = $_[0] =~ /^(.+)::/
		143	? $CTX{$1} \|\|= &_pkg_ctx ("$1")
		144	: $COLLECT;
102		145
103	$pkg = $CTX{$pkg} \|\|= &_pkg_ctx ($pkg);
104	$ctx->[2]{$pkg+0} = $pkg;	146	$ctx->[2]{$parent+0} = $parent;
105		147
106	$ctx	148	$ctx
107	}	149	}
108		150
109	=item AnyEvent::Log::log $level, $msg[, @args]	151	=item AnyEvent::Log::log $level, $msg[, @args]
110		152
111	Requests logging of the given C<$msg> with the given log level (1..9).	153	Requests logging of the given C<$msg> with the given log level, and
112	You can also use the following strings as log level: C<fatal> (1),	154	returns true if the message was logged I<somewhere>.
113	C<alert> (2), C<critical> (3), C<error> (4), C<warn> (5), C<note> (6),
114	C<info> (7), C<debug> (8), C<trace> (9).
115		155
116	For C<fatal> log levels, the program will abort.	156	For C<fatal> log levels, the program will abort.
117		157
118	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the	158	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the
119	C<$msg> is interpreted as an sprintf format string.	159	C<$msg> is interpreted as an sprintf format string.
…		…
125	supposed to return the message. It will be called only then the message	165	supposed to return the message. It will be called only then the message
126	actually gets logged, which is useful if it is costly to create the	166	actually gets logged, which is useful if it is costly to create the
127	message in the first place.	167	message in the first place.
128		168
129	Whether the given message will be logged depends on the maximum log level	169	Whether the given message will be logged depends on the maximum log level
130	and the caller's package.	170	and the caller's package. The return value can be used to ensure that
		171	messages or not "lost" - for example, when L<AnyEvent::Debug> detects a
		172	runtime error it tries to log it at C<die> level, but if that message is
		173	lost it simply uses warn.
131		174
132	Note that you can (and should) call this function as C<AnyEvent::log> or	175	Note that you can (and should) call this function as C<AnyEvent::log> or
133	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't	176	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't
134	need any additional functionality), as those functions will load the	177	need any additional functionality), as those functions will load the
135	logging module on demand only. They are also much shorter to write.	178	logging module on demand only. They are also much shorter to write.
…		…
152		195
153	=cut	196	=cut
154		197
155	# also allow syslog equivalent names	198	# also allow syslog equivalent names
156	our %STR2LEVEL = (	199	our %STR2LEVEL = (
157	fatal => 1, emerg => 1,	200	fatal => 1, emerg => 1, exit => 1,
158	alert => 2,	201	alert => 2,
159	critical => 3, crit => 3,	202	critical => 3, crit => 3,
160	error => 4, err => 4,	203	error => 4, err => 4, die => 4,
161	warn => 5, warning => 5,	204	warn => 5, warning => 5,
162	note => 6, notice => 6,	205	note => 6, notice => 6,
163	info => 7,	206	info => 7,
164	debug => 8,	207	debug => 8,
165	trace => 9,	208	trace => 9,
…		…
195	? $level+0	238	? $level+0
196	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";	239	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";
197		240
198	my $mask = 1 << $level;	241	my $mask = 1 << $level;
199		242
200	my (%seen, @ctx, $now, $fmt);	243	my ($success, %seen, @ctx, $now, $fmt);
201		244
202	do	245	do
203	{	246	{
204	# skip if masked	247	# skip if masked
205	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {	248	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {
…		…
209	# now get raw message, unless we have it already	252	# now get raw message, unless we have it already
210	unless ($now) {	253	unless ($now) {
211	$format = $format->() if ref $format;	254	$format = $format->() if ref $format;
212	$format = sprintf $format, @args if @args;	255	$format = sprintf $format, @args if @args;
213	$format =~ s/\n$//;	256	$format =~ s/\n$//;
214	$now = AE::now;	257	$now = now;
215	};	258	};
216		259
217	# format msg	260	# format msg
218	my $str = $ctx->[4]	261	my $str = $ctx->[4]
219	? $ctx->[4]($now, $_[0], $level, $format)	262	? $ctx->[4]($now, $_[0], $level, $format)
220	: $fmt \|\|= _format $now, $_[0], $level, $format;	263	: ($fmt \|\|= _format $now, $_[0], $level, $format);
221		264
		265	$success = 1;
		266
222	$ctx->[3]($str);	267	$ctx->[3]($str)
		268	or push @ctx, values %{ $ctx->[2] }; # not consumed - propagate
		269	} else {
		270	push @ctx, values %{ $ctx->[2] }; # not masked - propagate
223	}	271	}
224
225	# not masked, not consumed - propagate to parent contexts
226	push @ctx, values %{ $ctx->[2] };
227	}	272	}
228	}	273	}
229	while $ctx = pop @ctx;	274	while $ctx = pop @ctx;
230		275
231	exit 1 if $level <= 1;	276	exit 1 if $level <= 1;
		277
		278	$success
232	}	279	}
233		280
234	sub log($$;@) {	281	sub log($$;@) {
235	_log	282	_log
236	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	283	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
…		…
240	AnyEvent::log = AE::log = \&log;	287	AnyEvent::log = AE::log = \&log;
241		288
242	=item $logger = AnyEvent::Log::logger $level[, \$enabled]	289	=item $logger = AnyEvent::Log::logger $level[, \$enabled]
243		290
244	Creates a code reference that, when called, acts as if the	291	Creates a code reference that, when called, acts as if the
245	C<AnyEvent::Log::log> function was called at this point with the givne	292	C<AnyEvent::Log::log> function was called at this point with the given
246	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with	293	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with
247	the C<AnyEvent::Log::log> function:	294	the C<AnyEvent::Log::log> function:
248		295
249	my $debug_log = AnyEvent::Log::logger "debug";	296	my $debug_log = AnyEvent::Log::logger "debug";
250		297
…		…
275	# and later in your program	322	# and later in your program
276	$debug_log->("yo, stuff here") if $debug;	323	$debug_log->("yo, stuff here") if $debug;
277		324
278	$debug and $debug_log->("123");	325	$debug and $debug_log->("123");
279		326
280	Note: currently the enabled var is always true - that will be fixed in a
281	future version :)
282
283	=cut	327	=cut
284		328
285	our %LOGGER;	329	our %LOGGER;
286		330
287	# re-assess logging status for all loggers	331	# re-assess logging status for all loggers
288	sub _reassess {	332	sub _reassess {
		333	local $SIG{__DIE__};
		334	my $die = sub { die };
		335
289	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {	336	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {
290	my ($ctx, $level, $renabled) = @$_;	337	my ($ctx, $level, $renabled) = @$_;
291		338
292	# to detect whether a message would be logged, we # actually	339	# to detect whether a message would be logged, we actually
293	# try to log one and die. this isn't fast, but we can be	340	# try to log one and die. this isn't fast, but we can be
294	# sure that the logging decision is correct :)	341	# sure that the logging decision is correct :)
295		342
296	$$renabled = !eval {	343	$$renabled = !eval {
297	local $SIG{__DIE__};
298
299	_log $ctx, $level, sub { die };	344	_log $ctx, $level, $die;
300		345
301	1	346	1
302	};	347	};
303
304	$$renabled = 1; # TODO
305	}	348	}
306	}	349	}
307		350
308	sub _logger($;$) {	351	sub _logger {
309	my ($ctx, $level, $renabled) = @_;	352	my ($ctx, $level, $renabled) = @_;
310
311	$renabled \|\|= \my $enabled;
312		353
313	$$renabled = 1;	354	$$renabled = 1;
314		355
315	my $logger = [$ctx, $level, $renabled];	356	my $logger = [$ctx, $level, $renabled];
316		357
…		…
356	timestamp, context, level and string message and formats it in the way	397	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	398	it should be logged) and a logging callback (which is responsible for
358	actually logging the formatted message and telling C<AnyEvent::Log>	399	actually logging the formatted message and telling C<AnyEvent::Log>
359	whether it has consumed the message, or whether it should be propagated).	400	whether it has consumed the message, or whether it should be propagated).
360		401
361	For propagation, a context can have any number of attached I<parent	402	For propagation, a context can have any number of attached I<slave
362	contexts>. Any message that is neither masked by the logging mask nor	403	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	404	masked by the logging callback returning true will be passed to all slave
364	contexts.	405	contexts.
365		406
366	Each call to a logging function will log the message at most once per	407	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	408	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.	409	message can arrive at the same context via multiple paths.
…		…
372	By default, all logging contexts have an full set of log levels ("all"), a	413	By default, all logging contexts have an full set of log levels ("all"), a
373	disabled logging callback and the default formatting callback.	414	disabled logging callback and the default formatting callback.
374		415
375	Package contexts have the package name as logging title by default.	416	Package contexts have the package name as logging title by default.
376		417
377	They have exactly one parent - the context of the "parent" package. The	418	They have exactly one slave - the context of the "parent" package. The
378	parent package is simply defined to be the package name without the last	419	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>,	420	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
380	and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the	421	and C<AnyEvent> becomes ... C<$AnyEvent::Log::COLLECT> which is the
381	exception of the rule - just like the parent of any package name in	422	exception of the rule - just like the "parent" of any single-component
382	Perl is C<main>, the default parent of any top-level package context is	423	package name in Perl is C<main>, the default slave of any top-level
383	C<AnyEvent::Log::Top>.	424	package context is C<$AnyEvent::Log::COLLECT>.
384		425
385	Since perl packages form only an approximate hierarchy, this parent	426	Since perl packages form only an approximate hierarchy, this slave
386	context can of course be removed.	427	context can of course be removed.
387		428
388	All other (anonymous) contexts have no parents and an empty title by	429	All other (anonymous) contexts have no slaves and an empty title by
389	default.	430	default.
390		431
391	When the module is loaded it creates the default context called	432	When the module is loaded it creates the C<$AnyEvent::Log::LOG> logging
392	C<AnyEvent::Log::Default> (also stored in C<$AnyEvent::Log::Default>),	433	context that simply logs everything via C<warn>, without propagating
393	which simply logs everything to STDERR and doesn't propagate anything
394	anywhere by default. The purpose of the default context is to provide	434	anything anywhere by default. The purpose of this context is to provide
395	a convenient place to override the global logging target or to attach	435	a convenient place to override the global logging target or to attach
396	additional log targets. It's not meant for filtering.	436	additional log targets. It's not meant for filtering.
397		437
398	It then creates the root context called C<AnyEvent::Log::Root> (also	438	It then creates the C<$AnyEvent::Log::FILTER> context whose
399	stored in C<$AnyEvent::Log::Root>) and sets its log level set to all	439	purpose is to suppress all messages with priority higher
400	levels up to the one specified by C<$ENV{PERL_ANYEVENT_VERBOSE}>. It	440	than C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the
401	then attached the default logging context to it. The purpose of the root	441	C<$AnyEvent::Log::LOG> context to it. The purpose of the filter context
402	context is to simply provide filtering according to some global log level.	442	is to simply provide filtering according to some global log level.
403		443
404	Finally it creates the top-level package context called	444	Finally it creates the top-level package context C<$AnyEvent::Log::COLLECT>
405	C<AnyEvent::Log::Top> (also stored in, you might have guessed,	445	and attaches the C<$AnyEvent::Log::FILTER> context to it, but otherwise
406	C<$AnyEvent::Log::Top>) and attached the root context but otherwise leaves
407	it at default config. It's purpose is simply to collect all log messages	446	leaves it at default config. Its purpose is simply to collect all log
408	system-wide.	447	messages system-wide.
409		448
410	These three special contexts can also be referred to by the	449	The hierarchy is then:
411	package/context names C<AE::Log::Default>, C<AE::Log::Root> and
412	C<AE::Log::Top>.
413		450
		451	any package, eventually -> $COLLECT -> $FILTER -> $LOG
		452
414	The effect of all this is that log messages, by default, wander up	453	The effect of all this is that log messages, by default, wander up to the
415	to the root context where log messages with lower priority then	454	C<$AnyEvent::Log::COLLECT> context where all messages normally end up,
		455	from there to C<$AnyEvent::Log::FILTER> where log messages with lower
416	C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered away and then to the	456	priority then C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered out and then
417	AnyEvent::Log::Default context to be logged to STDERR.	457	to the C<$AnyEvent::Log::LOG> context to be passed to C<warn>.
418		458
419	Splitting the top level context into three contexts makes it easy to set	459	This makes it easy to set a global logging level (by modifying $FILTER),
420	a global logging level (by modifying the root context), but still allow	460	but still allow other contexts to send, for example, their debug and trace
421	other contexts to log, for example, their debug and trace messages to the
422	default target despite the global logging level, or to attach additional	461	messages to the $LOG target despite the global logging level, or to attach
423	log targets that log messages, regardless of the global logging level.	462	additional log targets that log messages, regardless of the global logging
		463	level.
424		464
425	It also makes it easy to replace the default STDERR-logger by something	465	It also makes it easy to modify the default warn-logger ($LOG) to
426	that logs to a file, or to attach additional logging targets.	466	something that logs to a file, or to attach additional logging targets
		467	(such as loggign to a file) by attaching it to $FILTER.
427		468
428	=head2 CREATING/FINDING/DESTROYING CONTEXTS	469	=head2 CREATING/FINDING/DESTROYING CONTEXTS
429		470
430	=over 4	471	=over 4
431		472
…		…
453	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"	494	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"
454	}	495	}
455		496
456	=item AnyEvent::Log::reset	497	=item AnyEvent::Log::reset
457		498
458	Deletes all contexts and recreates the default hierarchy, i.e. resets the	499	Resets all package contexts and recreates the default hierarchy if
459	logging subsystem to defaults.	500	necessary, i.e. resets the logging subsystem to defaults, as much as
		501	possible. This process keeps references to contexts held by other parts of
		502	the program intact.
460		503
461	This can be used to implement config-file (re-)loading: before loading a	504	This can be used to implement config-file (re-)loading: before loading a
462	configuration, reset all contexts.	505	configuration, reset all contexts.
463		506
464	=cut	507	=cut
465		508
466	sub reset {	509	sub reset {
467	@$_ = () for values %CTX; # just to be sure - to kill circular logging dependencies	510	# hard to kill complex data structures
468	%CTX = ();	511	# we "recreate" all package loggers and reset the hierarchy
		512	while (my ($k, $v) = each %CTX) {
		513	@$v = ($k, (1 << 10) - 1 - 1, { });
469		514
470	my $default = ctx undef;	515	$v->attach ($k =~ /^(.+)::/ ? $CTX{$1} : $AnyEvent::Log::COLLECT);
471	$default->title ("AnyEvent::Log::Default");
472	$default->log_cb (sub {
473	print STDERR shift;
474	0
475	});	516	}
476	$AnyEvent::Log::Default = $CTX{"AnyEvent::Log::Default"} = $CTX{"AE::Log::Default"} = $default;
477		517
478	my $root = ctx undef;	518	@$_ = ($_->[0], (1 << 10) - 1 - 1)
		519	for $LOG, $FILTER, $COLLECT;
		520
		521	#$LOG->slaves;
479	$root->title ("AnyEvent::Log::Root");	522	$LOG->title ('$AnyEvent::Log::LOG');
		523	$LOG->log_to_warn;
		524
		525	$FILTER->slaves ($LOG);
		526	$FILTER->title ('$AnyEvent::Log::FILTER');
480	$root->level ($AnyEvent::VERBOSE);	527	$FILTER->level ($AnyEvent::VERBOSE);
481	$root->attach ($default);
482	$AnyEvent::Log::Root = $CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $root;
483		528
484	my $top = ctx undef;	529	$COLLECT->slaves ($FILTER);
485	$top->title ("AnyEvent::Log::Top");	530	$COLLECT->title ('$AnyEvent::Log::COLLECT');
486	$top->attach ($root);	531
487	$AnyEvent::Log::Top = $CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $top;	532	_reassess;
488	}	533	}
		534
		535	# create the default logger contexts
		536	$LOG = ctx undef;
		537	$FILTER = ctx undef;
		538	$COLLECT = ctx undef;
489		539
490	AnyEvent::Log::reset;	540	AnyEvent::Log::reset;
491		541
492	# hello, CPAN, please catch me	542	# hello, CPAN, please catch me
493	package AnyEvent::Log::Default;
494	package AE::Log::Default;
495	package AnyEvent::Log::Root;
496	package AE::Log::Root;
497	package AnyEvent::Log::Top;	543	package AnyEvent::Log::LOG;
498	package AE::Log::Top;	544	package AE::Log::LOG;
		545	package AnyEvent::Log::FILTER;
		546	package AE::Log::FILTER;
		547	package AnyEvent::Log::COLLECT;
		548	package AE::Log::COLLECT;
499		549
500	package AnyEvent::Log::Ctx;	550	package AnyEvent::Log::Ctx;
501		551
502	# 0 1 2 3 4	552	# 0 1 2 3 4
503	# [$title, $level, %$parents, &$logcb, &$fmtcb]	553	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
504		554
505	=item $ctx = new AnyEvent::Log::Ctx methodname => param...	555	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
506		556
507	This is a convenience constructor that makes it simpler to construct	557	This is a convenience constructor that makes it simpler to construct
508	anonymous logging contexts.	558	anonymous logging contexts.
…		…
511	name as the key with the value as parameter, unless the value is an	561	name as the key with the value as parameter, unless the value is an
512	arrayref, in which case it calls the method with the contents of the	562	arrayref, in which case it calls the method with the contents of the
513	array. The methods are called in the same order as specified.	563	array. The methods are called in the same order as specified.
514		564
515	Example: create a new logging context and set both the default logging	565	Example: create a new logging context and set both the default logging
516	level, some parent contexts and a logging callback.	566	level, some slave contexts and a logging callback.
517		567
518	$ctx = new AnyEvent::Log::Ctx	568	$ctx = new AnyEvent::Log::Ctx
519	title => "dubious messages",	569	title => "dubious messages",
520	level => "error",	570	level => "error",
521	log_cb => sub { print STDOUT shift; 0 },	571	log_cb => sub { print STDOUT shift; 0 },
522	parents => [$ctx1, $ctx, $ctx2],	572	slaves => [$ctx1, $ctx, $ctx2],
523	;	573	;
524		574
525	=back	575	=back
526		576
527	=cut	577	=cut
…		…
640	AnyEvent::Log::_reassess;	690	AnyEvent::Log::_reassess;
641	}	691	}
642		692
643	=back	693	=back
644		694
645	=head3 PARENT CONTEXTS	695	=head3 SLAVE CONTEXTS
646		696
647	The following methods attach and detach another logging context to a	697	The following methods attach and detach another logging context to a
648	logging context.	698	logging context.
649		699
650	Log messages are propagated to all parent contexts, unless the logging	700	Log messages are propagated to all slave contexts, unless the logging
651	callback consumes the message.	701	callback consumes the message.
652		702
653	=over 4	703	=over 4
654		704
655	=item $ctx->attach ($ctx2[, $ctx3...])	705	=item $ctx->attach ($ctx2[, $ctx3...])
656		706
657	Attaches the given contexts as parents to this context. It is not an error	707	Attaches the given contexts as slaves to this context. It is not an error
658	to add a context twice (the second add will be ignored).	708	to add a context twice (the second add will be ignored).
659		709
660	A context can be specified either as package name or as a context object.	710	A context can be specified either as package name or as a context object.
661		711
662	=item $ctx->detach ($ctx2[, $ctx3...])	712	=item $ctx->detach ($ctx2[, $ctx3...])
663		713
664	Removes the given parents from this context - it's not an error to attempt	714	Removes the given slaves from this context - it's not an error to attempt
665	to remove a context that hasn't been added.	715	to remove a context that hasn't been added.
666		716
667	A context can be specified either as package name or as a context object.	717	A context can be specified either as package name or as a context object.
668		718
669	=item $ctx->parents ($ctx2[, $ctx3...])	719	=item $ctx->slaves ($ctx2[, $ctx3...])
670		720
671	Replaces all parents attached to this context by the ones given.	721	Replaces all slaves attached to this context by the ones given.
672		722
673	=cut	723	=cut
674		724
675	sub attach {	725	sub attach {
676	my $ctx = shift;	726	my $ctx = shift;
…		…
684		734
685	delete $ctx->[2]{$_+0}	735	delete $ctx->[2]{$_+0}
686	for map { AnyEvent::Log::ctx $_ } @_;	736	for map { AnyEvent::Log::ctx $_ } @_;
687	}	737	}
688		738
689	sub parents {	739	sub slaves {
690	undef $_[0][2];	740	undef $_[0][2];
691	&attach;	741	&attach;
692	}	742	}
693		743
694	=back	744	=back
695		745
696	=head3 MESSAGE LOGGING	746	=head3 LOG TARGETS
697		747
698	The following methods configure how the logging context actually does	748	The following methods configure how the logging context actually does
699	the logging (which consists of formatting the message and printing it or	749	the logging (which consists of formatting the message and printing it or
700	whatever it wants to do with it) and also allows you to log messages	750	whatever it wants to do with it).
701	directly to a context, without going via your package context.
702		751
703	=over 4	752	=over 4
704		753
705	=item $ctx->log_cb ($cb->($str))	754	=item $ctx->log_cb ($cb->($str)
706		755
707	Replaces the logging callback on the context (C<undef> disables the	756	Replaces the logging callback on the context (C<undef> disables the
708	logging callback).	757	logging callback).
709		758
710	The logging callback is responsible for handling formatted log messages	759	The logging callback is responsible for handling formatted log messages
711	(see C<fmt_cb> below) - normally simple text strings that end with a	760	(see C<fmt_cb> below) - normally simple text strings that end with a
712	newline (and are possibly multiline themselves).	761	newline (and are possibly multiline themselves).
713		762
714	It also has to return true iff it has consumed the log message, and false	763	It also has to return true iff it has consumed the log message, and false
715	if it hasn't. Consuming a message means that it will not be sent to any	764	if it hasn't. Consuming a message means that it will not be sent to any
716	parent context. When in doubt, return C<0> from your logging callback.	765	slave context. When in doubt, return C<0> from your logging callback.
717		766
718	Example: a very simple logging callback, simply dump the message to STDOUT	767	Example: a very simple logging callback, simply dump the message to STDOUT
719	and do not consume it.	768	and do not consume it.
720		769
721	$ctx->log_cb (sub { print STDERR shift; 0 });	770	$ctx->log_cb (sub { print STDERR shift; 0 });
…		…
729	your program.	778	your program.
730		779
731	$ctx->levels ("debug", "trace");	780	$ctx->levels ("debug", "trace");
732	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages	781	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages
733		782
734	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	783	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $orig_ctx, $level, $message))
735		784
736	Replaces the formatting callback on the context (C<undef> restores the	785	Replaces the formatting callback on the context (C<undef> restores the
737	default formatter).	786	default formatter).
738		787
739	The callback is passed the (possibly fractional) timestamp, the original	788	The callback is passed the (possibly fractional) timestamp, the original
740	logging context, the (numeric) logging level and the raw message string and needs to	789	logging context, the (numeric) logging level and the raw message string
741	return a formatted log message. In most cases this will be a string, but	790	and needs to return a formatted log message. In most cases this will be a
742	it could just as well be an array reference that just stores the values.	791	string, but it could just as well be an array reference that just stores
		792	the values.
		793
		794	If, for some reason, you want to use C<caller> to find out more baout the
		795	logger then you should walk up the call stack until you are no longer
		796	inside the C<AnyEvent::Log> package.
743		797
744	Example: format just the raw message, with numeric log level in angle	798	Example: format just the raw message, with numeric log level in angle
745	brackets.	799	brackets.
746		800
747	$ctx->fmt_cb (sub {	801	$ctx->fmt_cb (sub {
…		…
764	"$msg->[3]";	818	"$msg->[3]";
765		819
766	0	820	0
767	});	821	});
768		822
		823	=item $ctx->log_to_warn
		824
		825	Sets the C<log_cb> to simply use C<CORE::warn> to report any messages
		826	(usually this logs to STDERR).
		827
		828	=item $ctx->log_to_file ($path)
		829
		830	Sets the C<log_cb> to log to a file (by appending), unbuffered.
		831
		832	=item $ctx->log_to_path ($path)
		833
		834	Same as C<< ->log_to_file >>, but opens the file for each message. This
		835	is much slower, but allows you to change/move/rename/delete the file at
		836	basically any time.
		837
		838	Needless(?) to say, if you do not want to be bitten by some evil person
		839	calling C<chdir>, the path should be absolute. Doesn't help with
		840	C<chroot>, but hey...
		841
		842	=item $ctx->log_to_syslog ([$log_flags])
		843
		844	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and all
		845	the others in the obvious way. If specified, then the C<$log_flags> are
		846	simply or'ed onto the priority argument and can contain any C<LOG_xxx>
		847	flags valid for Sys::Syslog::syslog, except for the priority levels.
		848
		849	Note that this function also sets a C<fmt_cb> - the logging part requires
		850	an array reference with [$level, $str] as input.
		851
769	=cut	852	=cut
770		853
771	sub log_cb {	854	sub log_cb {
772	my ($ctx, $cb) = @_;	855	my ($ctx, $cb) = @_;
773		856
…		…
778	my ($ctx, $cb) = @_;	861	my ($ctx, $cb) = @_;
779		862
780	$ctx->[4] = $cb;	863	$ctx->[4] = $cb;
781	}	864	}
782		865
783	=item $ctx->log ($level, $msg[, @params])	866	sub log_to_warn {
		867	my ($ctx, $path) = @_;
784		868
785	Same as C<AnyEvent::Log::log>, but uses the given context as log context.	869	$ctx->log_cb (sub {
		870	warn shift;
		871	0
		872	});
		873	}
786		874
787	=item $logger = $ctx->logger ($level[, \$enabled])	875	sub log_to_file {
788		876	my ($ctx, $path) = @_;
789	Same as C<AnyEvent::Log::logger>, but uses the given context as log
790	context.
791
792	=cut
793
794	*log = \&AnyEvent::Log::_log;
795	*logger = \&AnyEvent::Log::_logger;
796
797	1;
798
799	=back
800
801	=head1 EXAMPLES
802
803	This section shows some common configurations.
804
805	=over 4
806
807	=item Setting the global logging level.
808
809	Either put PERL_ANYEVENT_VERBOSE=<number> into your environment before
810	running your program, or modify the log level of the root context:
811
812	PERL_ANYEVENT_VERBOSE=5 ./myprog
813
814	$AnyEvent::Log::Root->level ("warn");
815
816	=item Append all messages to a file instead of sending them to STDERR.
817
818	This is affected by the global logging level.
819		877
820	open my $fh, ">>", $path	878	open my $fh, ">>", $path
821	or die "$path: $!";	879	or die "$path: $!";
822		880
823	$AnyEvent::Log::Default->log_cb (sub {	881	$ctx->log_cb (sub {
824	syswrite $fh, shift;	882	syswrite $fh, shift;
825	0	883	0
826	});	884	});
		885	}
		886
		887	sub log_to_path {
		888	my ($ctx, $path) = @_;
		889
		890	$ctx->log_cb (sub {
		891	open my $fh, ">>", $path
		892	or die "$path: $!";
		893
		894	syswrite $fh, shift;
		895	0
		896	});
		897	}
		898
		899	sub log_to_syslog {
		900	my ($ctx, $flags) = @_;
		901
		902	require Sys::Syslog;
		903
		904	$ctx->fmt_cb (sub {
		905	my $str = $_[3];
		906	$str =~ s/\n(?=.)/\n+ /g;
		907
		908	[$_[2], "($_[1][0]) $str"]
		909	});
		910
		911	$ctx->log_cb (sub {
		912	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;
		913
		914	Sys::Syslog::syslog ($flags \| ($lvl - 1), $_)
		915	for split /\n/, $_[0][1];
		916
		917	0
		918	});
		919	}
		920
		921	=back
		922
		923	=head3 MESSAGE LOGGING
		924
		925	These methods allow you to log messages directly to a context, without
		926	going via your package context.
		927
		928	=over 4
		929
		930	=item $ctx->log ($level, $msg[, @params])
		931
		932	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
		933
		934	=item $logger = $ctx->logger ($level[, \$enabled])
		935
		936	Same as C<AnyEvent::Log::logger>, but uses the given context as log
		937	context.
		938
		939	=cut
		940
		941	*log = \&AnyEvent::Log::_log;
		942	*logger = \&AnyEvent::Log::_logger;
		943
		944	=back
		945
		946	=cut
		947
		948	package AnyEvent::Log;
		949
		950	=head1 CONFIGURATION VIA $ENV{PERL_ANYEVENT_LOG}
		951
		952	Logging can also be configured by setting the environment variable
		953	C<PERL_ANYEVENT_LOG> (or C<AE_LOG>).
		954
		955	The value consists of one or more logging context specifications separated
		956	by C<:> or whitespace. Each logging specification in turn starts with a
		957	context name, followed by C<=>, followed by zero or more comma-separated
		958	configuration directives, here are some examples:
		959
		960	# set default logging level
		961	filter=warn
		962
		963	# log to file instead of to stderr
		964	log=file=/tmp/mylog
		965
		966	# log to file in addition to stderr
		967	log=+%file:%file=file=/tmp/mylog
		968
		969	# enable debug log messages, log warnings and above to syslog
		970	filter=debug:log=+%warnings:%warnings=warn,syslog=LOG_LOCAL0
		971
		972	# log trace messages (only) from AnyEvent::Debug to file
		973	AnyEvent::Debug=+%trace:%trace=only,trace,file=/tmp/tracelog
		974
		975	A context name in the log specification can be any of the following:
		976
		977	=over 4
		978
		979	=item C<collect>, C<filter>, C<log>
		980
		981	Correspond to the three predefined C<$AnyEvent::Log::COLLECT>,
		982	C<AnyEvent::Log::FILTER> and C<$AnyEvent::Log::LOG> contexts.
		983
		984	=item C<%name>
		985
		986	Context names starting with a C<%> are anonymous contexts created when the
		987	name is first mentioned. The difference to package contexts is that by
		988	default they have no attached slaves.
		989
		990	=item a perl package name
		991
		992	Any other string references the logging context associated with the given
		993	Perl C<package>. In the unlikely case where you want to specify a package
		994	context that matches on of the other context name forms, you can add a
		995	C<::> to the package name to force interpretation as a package.
		996
		997	=back
		998
		999	The configuration specifications can be any number of the following:
		1000
		1001	=over 4
		1002
		1003	=item C<stderr>
		1004
		1005	Configures the context to use Perl's C<warn> function (which typically
		1006	logs to C<STDERR>). Works like C<log_to_warn>.
		1007
		1008	=item C<file=>I<path>
		1009
		1010	Configures the context to log to a file with the given path. Works like
		1011	C<log_to_file>.
		1012
		1013	=item C<path=>I<path>
		1014
		1015	Configures the context to log to a file with the given path. Works like
		1016	C<log_to_path>.
		1017
		1018	=item C<syslog> or C<syslog=>I<expr>
		1019
		1020	Configures the context to log to syslog. If I<expr> is given, then it is
		1021	evaluated in the L<Sys::Syslog> package, so you could use:
		1022
		1023	log=syslog=LOG_LOCAL0
		1024
		1025	=item C<nolog>
		1026
		1027	Configures the context to not log anything by itself, which is the
		1028	default. Same as C<< $ctx->log_cb (undef) >>.
		1029
		1030	=item C<0> or C<off>
		1031
		1032	Sets the logging level of the context ot C<0>, i.e. all messages will be
		1033	filtered out.
		1034
		1035	=item C<all>
		1036
		1037	Enables all logging levels, i.e. filtering will effectively be switched
		1038	off (the default).
		1039
		1040	=item C<only>
		1041
		1042	Disables all logging levels, and changes the interpretation of following
		1043	level specifications to enable the specified level only.
		1044
		1045	Example: only enable debug messages for a context.
		1046
		1047	context=only,debug
		1048
		1049	=item C<except>
		1050
		1051	Enables all logging levels, and changes the interpretation of following
		1052	level specifications to disable that level. Rarely used.
		1053
		1054	Example: enable all logging levels except fatal and trace (this is rather
		1055	nonsensical).
		1056
		1057	filter=exept,fatal,trace
		1058
		1059	=item C<level>
		1060
		1061	Enables all logging levels, and changes the interpretation of following
		1062	level specifications to be "that level or any higher priority
		1063	message". This is the default.
		1064
		1065	Example: log anything at or above warn level.
		1066
		1067	filter=warn
		1068
		1069	# or, more verbose
		1070	filter=only,level,warn
		1071
		1072	=item C<1>..C<9> or a logging level name (C<error>, C<debug> etc.)
		1073
		1074	A numeric loglevel or the name of a loglevel will be interpreted according
		1075	to the most recent C<only>, C<except> or C<level> directive. By default,
		1076	specifying a logging level enables that and any higher priority messages.
		1077
		1078	=item C<+>I<context>
		1079
		1080	Attaches the named context as slave to the context.
		1081
		1082	=item C<+>
		1083
		1084	A line C<+> detaches all contexts, i.e. clears the slave list from the
		1085	context. Anonymous (C<%name>) contexts have no attached slaves by default,
		1086	but package contexts have the parent context as slave by default.
		1087
		1088	Example: log messages from My::Module to a file, do not send them to the
		1089	default log collector.
		1090
		1091	My::Module=+,file=/tmp/mymodulelog
		1092
		1093	=back
		1094
		1095	Any character can be escaped by prefixing it with a C<\> (backslash), as
		1096	usual, so to log to a file containing a comma, colon, backslash and some
		1097	spaces in the filename, you would do this:
		1098
		1099	PERL_ANYEVENT_LOG='log=file=/some\ \:file\ with\,\ \\-escapes'
		1100
		1101	Since whitespace (which includes newlines) is allowed, it is fine to
		1102	specify multiple lines in C<PERL_ANYEVENT_LOG>, e.g.:
		1103
		1104	PERL_ANYEVENT_LOG="
		1105	filter=warn
		1106	AnyEvent::Debug=+%trace
		1107	%trace=only,trace,+log
		1108	" myprog
		1109
		1110	Also, in the unlikely case when you want to concatenate specifications,
		1111	use whitespace as separator, as C<::> will be interpreted as part of a
		1112	module name, an empty spec with two separators:
		1113
		1114	PERL_ANYEVENT_LOG="$PERL_ANYEVENT_LOG MyMod=debug"
		1115
		1116	=cut
		1117
		1118	for (my $spec = $ENV{PERL_ANYEVENT_LOG}) {
		1119	my %anon;
		1120
		1121	my $pkg = sub {
		1122	$_[0] eq "log" ? $LOG
		1123	: $_[0] eq "filter" ? $FILTER
		1124	: $_[0] eq "collect" ? $COLLECT
		1125	: $_[0] =~ /^%(.+)$/ ? ($anon{$1} \|\|= ctx undef)
		1126	: $_[0] =~ /^(.*?)(?:::)?$/ ? ctx "$1" # egad :/
		1127	: die # never reached?
		1128	};
		1129
		1130	/\G[[:space:]]+/gc; # skip initial whitespace
		1131
		1132	while (/\G((?:[^:=[:space:]]+\|::\|\\.)+)=/gc) {
		1133	my $ctx = $pkg->($1);
		1134	my $level = "level";
		1135
		1136	while (/\G((?:[^,:[:space:]]+\|::\|\\.)+)/gc) {
		1137	for ("$1") {
		1138	if ($_ eq "stderr" ) { $ctx->log_to_warn;
		1139	} elsif (/^file=(.+)/ ) { $ctx->log_to_file ("$1");
		1140	} elsif (/^path=(.+)/ ) { $ctx->log_to_path ("$1");
		1141	} elsif (/syslog(?:=(.*))?/ ) { require Sys::Syslog; $ctx->log_to_syslog (eval "package Sys::Syslog; $1");
		1142	} elsif ($_ eq "nolog" ) { $ctx->log_cb (undef);
		1143	} elsif (/^\+(.+)$/ ) { $ctx->attach ($pkg->("$1"));
		1144	} elsif ($_ eq "+" ) { $ctx->slaves;
		1145	} elsif ($_ eq "off" or $_ eq "0") { $ctx->level (0);
		1146	} elsif ($_ eq "all" ) { $ctx->level ("all");
		1147	} elsif ($_ eq "level" ) { $ctx->level ("all"); $level = "level";
		1148	} elsif ($_ eq "only" ) { $ctx->level ("off"); $level = "enable";
		1149	} elsif ($_ eq "except" ) { $ctx->level ("all"); $level = "disable";
		1150	} elsif (/^\d$/ ) { $ctx->$level ($_);
		1151	} elsif (exists $STR2LEVEL{$_} ) { $ctx->$level ($_);
		1152	} else { die "PERL_ANYEVENT_LOG ($spec): parse error at '$_'\n";
		1153	}
		1154	}
		1155
		1156	/\G,/gc or last;
		1157	}
		1158
		1159	/\G[:[:space:]]+/gc or last;
		1160	}
		1161
		1162	/\G[[:space:]]+/gc; # skip trailing whitespace
		1163
		1164	if (/\G(.+)/g) {
		1165	die "PERL_ANYEVENT_LOG ($spec): parse error at '$1'\n";
		1166	}
		1167	}
		1168
		1169	1;
		1170
		1171	=head1 EXAMPLES
		1172
		1173	This section shows some common configurations, both as code, and as
		1174	C<PERL_ANYEVENT_LOG> string.
		1175
		1176	=over 4
		1177
		1178	=item Setting the global logging level.
		1179
		1180	Either put C<PERL_ANYEVENT_VERBOSE=><number> into your environment before
		1181	running your program, use C<PERL_ANYEVENT_LOG> or modify the log level of
		1182	the root context at runtime:
		1183
		1184	PERL_ANYEVENT_VERBOSE=5 ./myprog
		1185
		1186	PERL_ANYEVENT_LOG=log=warn
		1187
		1188	$AnyEvent::Log::FILTER->level ("warn");
		1189
		1190	=item Append all messages to a file instead of sending them to STDERR.
		1191
		1192	This is affected by the global logging level.
		1193
		1194	$AnyEvent::Log::LOG->log_to_file ($path);
		1195
		1196	PERL_ANYEVENT_LOG=log=file=/some/path
827		1197
828	=item Write all messages with priority C<error> and higher to a file.	1198	=item Write all messages with priority C<error> and higher to a file.
829		1199
830	This writes them only when the global logging level allows it, because	1200	This writes them only when the global logging level allows it, because
831	it is attached to the default context which is invoked I<after> global	1201	it is attached to the default context which is invoked I<after> global
832	filtering.	1202	filtering.
833		1203
834	open my $fh, ">>", $path	1204	$AnyEvent::Log::FILTER->attach
835	or die "$path: $!";	1205	new AnyEvent::Log::Ctx log_to_file => $path);
836		1206
837	$AnyEvent::Log::Default->attach (new AnyEvent::Log::Ctx	1207	PERL_ANYEVENT_LOG=filter=+%filelogger:%filelogger=file=/some/path
838	log_cb => sub { syswrite $fh, shift; 0 });
839		1208
840	This writes them regardless of the global logging level, because it is	1209	This writes them regardless of the global logging level, because it is
841	attached to the toplevel context, which receives all messages I<before>	1210	attached to the toplevel context, which receives all messages I<before>
842	the global filtering.	1211	the global filtering.
843		1212
844	$AnyEvent::Log::Top->attach (new AnyEvent::Log::Ctx	1213	$AnyEvent::Log::COLLECT->attach (
845	log_cb => sub { syswrite $fh, shift; 0 });	1214	new AnyEvent::Log::Ctx log_to_file => $path);
846		1215
		1216	PERL_ANYEVENT_LOG=%filelogger=file=/some/path:collect=+%filelogger
		1217
847	In both cases, messages are still written to STDOUT.	1218	In both cases, messages are still written to STDERR.
848		1219
849	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).	1220	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
850		1221
851	Attach the CyAnyEvent::Log::Default> context to the C<AnyEvent::Debug>	1222	Attach the C<$AnyEvent::Log::LOG> context to the C<AnyEvent::Debug>
852	context and increase the C<AnyEvent::Debug> logging level - this simply
853	circumvents the global filtering for trace messages.	1223	context - this simply circumvents the global filtering for trace messages.
854		1224
855	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;	1225	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
856	$debug->attach ($AnyEvent::Log::Default);	1226	$debug->attach ($AnyEvent::Log::LOG);
857	$debug->levels ("trace"); # not "level"!
858		1227
859	This of course works for any package.	1228	PERL_ANYEVENT_LOG=AnyEvent::Debug=+log
		1229
		1230	This of course works for any package, not just L<AnyEvent::Debug>, but
		1231	assumes the log level for AnyEvent::Debug hasn't been changed from the
		1232	default.
860		1233
861	=back	1234	=back
862		1235
863	=head1 AUTHOR	1236	=head1 AUTHOR
864		1237
865	Marc Lehmann <schmorp@schmorp.de>	1238	Marc Lehmann <schmorp@schmorp.de>
866	http://home.schmorp.de/	1239	http://home.schmorp.de/
867		1240
868	=cut	1241	=cut
		1242

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents): Revision 1.13 by root, Sat Aug 20 01:34:12 2011 UTC vs. Revision 1.36 by root, Thu Aug 25 05:39:47 2011 UTC

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.13 by root, Sat Aug 20 01:34:12 2011 UTC vs.
Revision 1.36 by root, Thu Aug 25 05:39:47 2011 UTC