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

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.15 by root, Sat Aug 20 02:16:59 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
62	The amount of documentation might indicate otherwise, but the module is	64	The amount of documentation might indicate otherwise, but the runtime part
63	still just 240 lines or so.	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.
64		98
65	=head1 LOGGING FUNCTIONS	99	=head1 LOGGING FUNCTIONS
66		100
67	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
68	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
69	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
70	loaded.	104	loaded.
71		105
72	=over 4	106	=over 4
73		107
…		…
80		114
81	use AnyEvent (); BEGIN { AnyEvent::common_sense }	115	use AnyEvent (); BEGIN { AnyEvent::common_sense }
82	use AnyEvent::Util ();	116	use AnyEvent::Util ();
83		117
84	our $VERSION = $AnyEvent::VERSION;	118	our $VERSION = $AnyEvent::VERSION;
		119
		120	our ($COLLECT, $FILTER, $LOG);
85		121
86	our ($now_int, $now_str1, $now_str2);	122	our ($now_int, $now_str1, $now_str2);
87		123
88	# Format Time, not public - yet?	124	# Format Time, not public - yet?
89	sub ft($) {	125	sub ft($) {
…		…
94	if $now_int != $i;	130	if $now_int != $i;
95		131
96	"$now_str1$f$now_str2"	132	"$now_str1$f$now_str2"
97	}	133	}
98		134
99	our %CTX; # all logging contexts	135	our %CTX; # all package contexts
100		136
101	# creates a default package context object for the given package	137	# creates a default package context object for the given package
102	sub _pkg_ctx($) {	138	sub _pkg_ctx($) {
103	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";	139	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";
104		140
105	# link "parent" package	141	# link "parent" package
106	my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "AE::Log::Top";	142	my $parent = $_[0] =~ /^(.+)::/
		143	? $CTX{$1} \|\|= &_pkg_ctx ("$1")
		144	: $COLLECT;
107		145
108	$pkg = $CTX{$pkg} \|\|= &_pkg_ctx ($pkg);
109	$ctx->[2]{$pkg+0} = $pkg;	146	$ctx->[2]{$parent+0} = $parent;
110		147
111	$ctx	148	$ctx
112	}	149	}
113		150
114	=item AnyEvent::Log::log $level, $msg[, @args]	151	=item AnyEvent::Log::log $level, $msg[, @args]
115		152
116	Requests logging of the given C<$msg> with the given log level (1..9).	153	Requests logging of the given C<$msg> with the given log level, and
117	You can also use the following strings as log level: C<fatal> (1),	154	returns true if the message was logged I<somewhere>.
118	C<alert> (2), C<critical> (3), C<error> (4), C<warn> (5), C<note> (6),
119	C<info> (7), C<debug> (8), C<trace> (9).
120		155
121	For C<fatal> log levels, the program will abort.	156	For C<fatal> log levels, the program will abort.
122		157
123	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the	158	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the
124	C<$msg> is interpreted as an sprintf format string.	159	C<$msg> is interpreted as an sprintf format string.
…		…
130	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
131	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
132	message in the first place.	167	message in the first place.
133		168
134	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
135	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.
136		174
137	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
138	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
139	need any additional functionality), as those functions will load the	177	need any additional functionality), as those functions will load the
140	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.
…		…
157		195
158	=cut	196	=cut
159		197
160	# also allow syslog equivalent names	198	# also allow syslog equivalent names
161	our %STR2LEVEL = (	199	our %STR2LEVEL = (
162	fatal => 1, emerg => 1,	200	fatal => 1, emerg => 1, exit => 1,
163	alert => 2,	201	alert => 2,
164	critical => 3, crit => 3,	202	critical => 3, crit => 3,
165	error => 4, err => 4,	203	error => 4, err => 4, die => 4,
166	warn => 5, warning => 5,	204	warn => 5, warning => 5,
167	note => 6, notice => 6,	205	note => 6, notice => 6,
168	info => 7,	206	info => 7,
169	debug => 8,	207	debug => 8,
170	trace => 9,	208	trace => 9,
…		…
200	? $level+0	238	? $level+0
201	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";	239	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";
202		240
203	my $mask = 1 << $level;	241	my $mask = 1 << $level;
204		242
205	my (%seen, @ctx, $now, $fmt);	243	my ($success, %seen, @ctx, $now, $fmt);
206		244
207	do	245	do
208	{	246	{
209	# skip if masked	247	# skip if masked
210	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {	248	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {
…		…
214	# now get raw message, unless we have it already	252	# now get raw message, unless we have it already
215	unless ($now) {	253	unless ($now) {
216	$format = $format->() if ref $format;	254	$format = $format->() if ref $format;
217	$format = sprintf $format, @args if @args;	255	$format = sprintf $format, @args if @args;
218	$format =~ s/\n$//;	256	$format =~ s/\n$//;
219	$now = AE::now;	257	$now = now;
220	};	258	};
221		259
222	# format msg	260	# format msg
223	my $str = $ctx->[4]	261	my $str = $ctx->[4]
224	? $ctx->[4]($now, $_[0], $level, $format)	262	? $ctx->[4]($now, $_[0], $level, $format)
225	: $fmt \|\|= _format $now, $_[0], $level, $format;	263	: ($fmt \|\|= _format $now, $_[0], $level, $format);
226		264
		265	$success = 1;
		266
227	$ctx->[3]($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
228	}	271	}
229
230	# not masked, not consumed - propagate to parent contexts
231	push @ctx, values %{ $ctx->[2] };
232	}	272	}
233	}	273	}
234	while $ctx = pop @ctx;	274	while $ctx = pop @ctx;
235		275
236	exit 1 if $level <= 1;	276	exit 1 if $level <= 1;
		277
		278	$success
237	}	279	}
238		280
239	sub log($$;@) {	281	sub log($$;@) {
240	_log	282	_log
241	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	283	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
…		…
245	AnyEvent::log = AE::log = \&log;	287	AnyEvent::log = AE::log = \&log;
246		288
247	=item $logger = AnyEvent::Log::logger $level[, \$enabled]	289	=item $logger = AnyEvent::Log::logger $level[, \$enabled]
248		290
249	Creates a code reference that, when called, acts as if the	291	Creates a code reference that, when called, acts as if the
250	C<AnyEvent::Log::log> function was called at this point with the givne	292	C<AnyEvent::Log::log> function was called at this point with the given
251	level. C<$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
252	the C<AnyEvent::Log::log> function:	294	the C<AnyEvent::Log::log> function:
253		295
254	my $debug_log = AnyEvent::Log::logger "debug";	296	my $debug_log = AnyEvent::Log::logger "debug";
255		297
…		…
280	# and later in your program	322	# and later in your program
281	$debug_log->("yo, stuff here") if $debug;	323	$debug_log->("yo, stuff here") if $debug;
282		324
283	$debug and $debug_log->("123");	325	$debug and $debug_log->("123");
284		326
285	Note: currently the enabled var is always true - that will be fixed in a
286	future version :)
287
288	=cut	327	=cut
289		328
290	our %LOGGER;	329	our %LOGGER;
291		330
292	# re-assess logging status for all loggers	331	# re-assess logging status for all loggers
293	sub _reassess {	332	sub _reassess {
		333	local $SIG{__DIE__};
		334	my $die = sub { die };
		335
294	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {	336	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {
295	my ($ctx, $level, $renabled) = @$_;	337	my ($ctx, $level, $renabled) = @$_;
296		338
297	# to detect whether a message would be logged, we # actually	339	# to detect whether a message would be logged, we actually
298	# 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
299	# sure that the logging decision is correct :)	341	# sure that the logging decision is correct :)
300		342
301	$$renabled = !eval {	343	$$renabled = !eval {
302	local $SIG{__DIE__};
303
304	_log $ctx, $level, sub { die };	344	_log $ctx, $level, $die;
305		345
306	1	346	1
307	};	347	};
308
309	$$renabled = 1; # TODO
310	}	348	}
311	}	349	}
312		350
313	sub _logger {	351	sub _logger {
314	my ($ctx, $level, $renabled) = @_;	352	my ($ctx, $level, $renabled) = @_;
…		…
359	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
360	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
361	actually logging the formatted message and telling C<AnyEvent::Log>	399	actually logging the formatted message and telling C<AnyEvent::Log>
362	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).
363		401
364	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
365	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
366	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
367	contexts.	405	contexts.
368		406
369	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
370	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
371	message can arrive at the same context via multiple paths.	409	message can arrive at the same context via multiple paths.
…		…
375	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
376	disabled logging callback and the default formatting callback.	414	disabled logging callback and the default formatting callback.
377		415
378	Package contexts have the package name as logging title by default.	416	Package contexts have the package name as logging title by default.
379		417
380	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
381	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
382	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,	420	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
383	and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the	421	and C<AnyEvent> becomes ... C<$AnyEvent::Log::COLLECT> which is the
384	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
385	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
386	C<AnyEvent::Log::Top>.	424	package context is C<$AnyEvent::Log::COLLECT>.
387		425
388	Since perl packages form only an approximate hierarchy, this parent	426	Since perl packages form only an approximate hierarchy, this slave
389	context can of course be removed.	427	context can of course be removed.
390		428
391	All other (anonymous) contexts have no parents and an empty title by	429	All other (anonymous) contexts have no slaves and an empty title by
392	default.	430	default.
393		431
394	When the module is loaded it creates the default context called	432	When the module is loaded it creates the C<$AnyEvent::Log::LOG> logging
395	C<AnyEvent::Log::Default> (also stored in C<$AnyEvent::Log::Default>),	433	context that simply logs everything via C<warn>, without propagating
396	which simply logs everything via C<warn> and doesn't propagate anything
397	anywhere by default. The purpose of the default context is to provide	434	anything anywhere by default. The purpose of this context is to provide
398	a convenient place to override the global logging target or to attach	435	a convenient place to override the global logging target or to attach
399	additional log targets. It's not meant for filtering.	436	additional log targets. It's not meant for filtering.
400		437
401	It then creates the root context called C<AnyEvent::Log::Root> (also	438	It then creates the C<$AnyEvent::Log::FILTER> context whose
402	stored in C<$AnyEvent::Log::Root>) and sets its log level set to all	439	purpose is to suppress all messages with priority higher
403	levels up to the one specified by C<$ENV{PERL_ANYEVENT_VERBOSE}>. It	440	than C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the
404	then attached the default logging context to it. The purpose of the root	441	C<$AnyEvent::Log::LOG> context to it. The purpose of the filter context
405	context is to simply provide filtering according to some global log level.	442	is to simply provide filtering according to some global log level.
406		443
407	Finally it creates the top-level package context called	444	Finally it creates the top-level package context C<$AnyEvent::Log::COLLECT>
408	C<AnyEvent::Log::Top> (also stored in, you might have guessed,	445	and attaches the C<$AnyEvent::Log::FILTER> context to it, but otherwise
409	C<$AnyEvent::Log::Top>) and attached the root context but otherwise leaves
410	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
411	system-wide.	447	messages system-wide.
412		448
413	These three special contexts can also be referred to by the	449	The hierarchy is then:
414	package/context names C<AE::Log::Default>, C<AE::Log::Root> and
415	C<AE::Log::Top>.
416		450
		451	any package, eventually -> $COLLECT -> $FILTER -> $LOG
		452
417	The effect of all this is that log messages, by default, wander up	453	The effect of all this is that log messages, by default, wander up to the
418	to the root context where log messages with lower priority then	454	C<$AnyEvent::Log::COLLECT> context where all messages normally end up,
		455	from there to C<$AnyEvent::Log::FILTER> where log messages with lower
419	C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered away and then to the	456	priority then C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered out and then
420	AnyEvent::Log::Default context to be passed to C<warn>.	457	to the C<$AnyEvent::Log::LOG> context to be passed to C<warn>.
421		458
422	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),
423	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
424	other contexts to log, for example, their debug and trace messages to the
425	default target despite the global logging level, or to attach additional	461	messages to the $LOG target despite the global logging level, or to attach
426	log targets that log messages, regardless of the global logging level.	462	additional log targets that log messages, regardless of the global logging
		463	level.
427		464
428	It also makes it easy to replace the default warn-logger by something that	465	It also makes it easy to modify the default warn-logger ($LOG) to
429	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 $FILTER.
430		468
431	=head2 CREATING/FINDING/DESTROYING CONTEXTS	469	=head2 CREATING/FINDING/DESTROYING CONTEXTS
432		470
433	=over 4	471	=over 4
434		472
…		…
456	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"	494	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"
457	}	495	}
458		496
459	=item AnyEvent::Log::reset	497	=item AnyEvent::Log::reset
460		498
461	Resets all package contexts contexts and recreates the default hierarchy	499	Resets all package contexts and recreates the default hierarchy if
462	if necessary, i.e. resets the logging subsystem to defaults.	500	necessary, i.e. resets the logging subsystem to defaults, as much as
		501	possible. This process keeps references to contexts held by other parts of
		502	the program intact.
463		503
464	This can be used to implement config-file (re-)loading: before loading a	504	This can be used to implement config-file (re-)loading: before loading a
465	configuration, reset all contexts.	505	configuration, reset all contexts.
466		506
467	Note that this currently destroys all logger callbacks - bug me if you
468	need this fixed :)
469
470	=cut	507	=cut
471		508
472	sub reset {	509	sub reset {
473	# hard to kill complex data structures	510	# hard to kill complex data structures
474	# we recreate all package loggers and reset the hierarchy	511	# we "recreate" all package loggers and reset the hierarchy
475	while (my ($k, $v) = each %CTX) {	512	while (my ($k, $v) = each %CTX) {
476	@$v = ($k, (1 << 10) - 1 - 1, { });	513	@$v = ($k, (1 << 10) - 1 - 1, { });
477		514
478	my $pkg = $k =~ /^(.+)::/ ? $1 : "AE::Log::Top";	515	$v->attach ($k =~ /^(.+)::/ ? $CTX{$1} : $AnyEvent::Log::COLLECT);
479	$v->attach ($CTX{$pkg});
480	}	516	}
481		517
482	$AnyEvent::Log::Default->parents;	518	@$_ = ($_->[0], (1 << 10) - 1 - 1)
483	$AnyEvent::Log::Default->title ("AnyEvent::Log::Default");	519	for $LOG, $FILTER, $COLLECT;
484	$AnyEvent::Log::Default->log_cb (sub {
485	warn shift;
486	0
487	});
488	$CTX{"AnyEvent::Log::Default"} = $CTX{"AE::Log::Default"} = $AnyEvent::Log::Default;
489		520
490	$AnyEvent::Log::Root->parents ($AnyEvent::Log::Default);	521	#$LOG->slaves;
491	$AnyEvent::Log::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');
492	$AnyEvent::Log::Root->level ($AnyEvent::VERBOSE);	527	$FILTER->level ($AnyEvent::VERBOSE);
493	$CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $AnyEvent::Log::Root;
494		528
495	$AnyEvent::Log::Top->parents ($AnyEvent::Log::Root);	529	$COLLECT->slaves ($FILTER);
496	$AnyEvent::Log::Top->title ("AnyEvent::Log::Top");	530	$COLLECT->title ('$AnyEvent::Log::COLLECT');
497	$CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $AnyEvent::Log::Top;
498		531
499	_reassess;	532	_reassess;
500	}	533	}
501		534
502	# create the default logger contexts	535	# create the default logger contexts
503	$AnyEvent::Log::Default = ctx undef;	536	$LOG = ctx undef;
504	$AnyEvent::Log::Root = ctx undef;	537	$FILTER = ctx undef;
505	$AnyEvent::Log::Top = ctx undef;	538	$COLLECT = ctx undef;
506		539
507	AnyEvent::Log::reset;	540	AnyEvent::Log::reset;
508		541
509	# hello, CPAN, please catch me	542	# hello, CPAN, please catch me
510	package AnyEvent::Log::Default;
511	package AE::Log::Default;
512	package AnyEvent::Log::Root;
513	package AE::Log::Root;
514	package AnyEvent::Log::Top;	543	package AnyEvent::Log::LOG;
515	package AE::Log::Top;	544	package AE::Log::LOG;
		545	package AnyEvent::Log::FILTER;
		546	package AE::Log::FILTER;
		547	package AnyEvent::Log::COLLECT;
		548	package AE::Log::COLLECT;
516		549
517	package AnyEvent::Log::Ctx;	550	package AnyEvent::Log::Ctx;
518		551
519	# 0 1 2 3 4	552	# 0 1 2 3 4
520	# [$title, $level, %$parents, &$logcb, &$fmtcb]	553	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
521		554
522	=item $ctx = new AnyEvent::Log::Ctx methodname => param...	555	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
523		556
524	This is a convenience constructor that makes it simpler to construct	557	This is a convenience constructor that makes it simpler to construct
525	anonymous logging contexts.	558	anonymous logging contexts.
…		…
528	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
529	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
530	array. The methods are called in the same order as specified.	563	array. The methods are called in the same order as specified.
531		564
532	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
533	level, some parent contexts and a logging callback.	566	level, some slave contexts and a logging callback.
534		567
535	$ctx = new AnyEvent::Log::Ctx	568	$ctx = new AnyEvent::Log::Ctx
536	title => "dubious messages",	569	title => "dubious messages",
537	level => "error",	570	level => "error",
538	log_cb => sub { print STDOUT shift; 0 },	571	log_cb => sub { print STDOUT shift; 0 },
539	parents => [$ctx1, $ctx, $ctx2],	572	slaves => [$ctx1, $ctx, $ctx2],
540	;	573	;
541		574
542	=back	575	=back
543		576
544	=cut	577	=cut
…		…
657	AnyEvent::Log::_reassess;	690	AnyEvent::Log::_reassess;
658	}	691	}
659		692
660	=back	693	=back
661		694
662	=head3 PARENT CONTEXTS	695	=head3 SLAVE CONTEXTS
663		696
664	The following methods attach and detach another logging context to a	697	The following methods attach and detach another logging context to a
665	logging context.	698	logging context.
666		699
667	Log messages are propagated to all parent contexts, unless the logging	700	Log messages are propagated to all slave contexts, unless the logging
668	callback consumes the message.	701	callback consumes the message.
669		702
670	=over 4	703	=over 4
671		704
672	=item $ctx->attach ($ctx2[, $ctx3...])	705	=item $ctx->attach ($ctx2[, $ctx3...])
673		706
674	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
675	to add a context twice (the second add will be ignored).	708	to add a context twice (the second add will be ignored).
676		709
677	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.
678		711
679	=item $ctx->detach ($ctx2[, $ctx3...])	712	=item $ctx->detach ($ctx2[, $ctx3...])
680		713
681	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
682	to remove a context that hasn't been added.	715	to remove a context that hasn't been added.
683		716
684	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.
685		718
686	=item $ctx->parents ($ctx2[, $ctx3...])	719	=item $ctx->slaves ($ctx2[, $ctx3...])
687		720
688	Replaces all parents attached to this context by the ones given.	721	Replaces all slaves attached to this context by the ones given.
689		722
690	=cut	723	=cut
691		724
692	sub attach {	725	sub attach {
693	my $ctx = shift;	726	my $ctx = shift;
…		…
701		734
702	delete $ctx->[2]{$_+0}	735	delete $ctx->[2]{$_+0}
703	for map { AnyEvent::Log::ctx $_ } @_;	736	for map { AnyEvent::Log::ctx $_ } @_;
704	}	737	}
705		738
706	sub parents {	739	sub slaves {
707	undef $_[0][2];	740	undef $_[0][2];
708	&attach;	741	&attach;
709	}	742	}
710		743
711	=back	744	=back
712		745
713	=head3 MESSAGE LOGGING	746	=head3 LOG TARGETS
714		747
715	The following methods configure how the logging context actually does	748	The following methods configure how the logging context actually does
716	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
717	whatever it wants to do with it) and also allows you to log messages	750	whatever it wants to do with it).
718	directly to a context, without going via your package context.
719		751
720	=over 4	752	=over 4
721		753
722	=item $ctx->log_cb ($cb->($str))	754	=item $ctx->log_cb ($cb->($str)
723		755
724	Replaces the logging callback on the context (C<undef> disables the	756	Replaces the logging callback on the context (C<undef> disables the
725	logging callback).	757	logging callback).
726		758
727	The logging callback is responsible for handling formatted log messages	759	The logging callback is responsible for handling formatted log messages
728	(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
729	newline (and are possibly multiline themselves).	761	newline (and are possibly multiline themselves).
730		762
731	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
732	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
733	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.
734		766
735	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
736	and do not consume it.	768	and do not consume it.
737		769
738	$ctx->log_cb (sub { print STDERR shift; 0 });	770	$ctx->log_cb (sub { print STDERR shift; 0 });
…		…
746	your program.	778	your program.
747		779
748	$ctx->levels ("debug", "trace");	780	$ctx->levels ("debug", "trace");
749	$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
750		782
751	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	783	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $orig_ctx, $level, $message))
752		784
753	Replaces the formatting callback on the context (C<undef> restores the	785	Replaces the formatting callback on the context (C<undef> restores the
754	default formatter).	786	default formatter).
755		787
756	The callback is passed the (possibly fractional) timestamp, the original	788	The callback is passed the (possibly fractional) timestamp, the original
757	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
758	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
759	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.
760		797
761	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
762	brackets.	799	brackets.
763		800
764	$ctx->fmt_cb (sub {	801	$ctx->fmt_cb (sub {
…		…
781	"$msg->[3]";	818	"$msg->[3]";
782		819
783	0	820	0
784	});	821	});
785		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, $str] as input.
		851
786	=cut	852	=cut
787		853
788	sub log_cb {	854	sub log_cb {
789	my ($ctx, $cb) = @_;	855	my ($ctx, $cb) = @_;
790		856
…		…
795	my ($ctx, $cb) = @_;	861	my ($ctx, $cb) = @_;
796		862
797	$ctx->[4] = $cb;	863	$ctx->[4] = $cb;
798	}	864	}
799		865
800	=item $ctx->log ($level, $msg[, @params])	866	sub log_to_warn {
		867	my ($ctx, $path) = @_;
801		868
802	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	}
803		874
804	=item $logger = $ctx->logger ($level[, \$enabled])	875	sub log_to_file {
805		876	my ($ctx, $path) = @_;
806	Same as C<AnyEvent::Log::logger>, but uses the given context as log
807	context.
808
809	=cut
810
811	*log = \&AnyEvent::Log::_log;
812	*logger = \&AnyEvent::Log::_logger;
813
814	1;
815
816	=back
817
818	=head1 EXAMPLES
819
820	This section shows some common configurations.
821
822	=over 4
823
824	=item Setting the global logging level.
825
826	Either put PERL_ANYEVENT_VERBOSE=<number> into your environment before
827	running your program, or modify the log level of the root context:
828
829	PERL_ANYEVENT_VERBOSE=5 ./myprog
830
831	$AnyEvent::Log::Root->level ("warn");
832
833	=item Append all messages to a file instead of sending them to STDERR.
834
835	This is affected by the global logging level.
836		877
837	open my $fh, ">>", $path	878	open my $fh, ">>", $path
838	or die "$path: $!";	879	or die "$path: $!";
839		880
840	$AnyEvent::Log::Default->log_cb (sub {	881	$ctx->log_cb (sub {
841	syswrite $fh, shift;	882	syswrite $fh, shift;
842	0	883	0
843	});	884	});
		885	}
		886
		887	sub log_to_path {
		888	my ($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
844		1197
845	=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.
846		1199
847	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
848	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
849	filtering.	1202	filtering.
850		1203
851	open my $fh, ">>", $path	1204	$AnyEvent::Log::FILTER->attach
852	or die "$path: $!";	1205	new AnyEvent::Log::Ctx log_to_file => $path);
853		1206
854	$AnyEvent::Log::Default->attach (new AnyEvent::Log::Ctx	1207	PERL_ANYEVENT_LOG=filter=+%filelogger:%filelogger=file=/some/path
855	log_cb => sub { syswrite $fh, shift; 0 });
856		1208
857	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
858	attached to the toplevel context, which receives all messages I<before>	1210	attached to the toplevel context, which receives all messages I<before>
859	the global filtering.	1211	the global filtering.
860		1212
861	$AnyEvent::Log::Top->attach (new AnyEvent::Log::Ctx	1213	$AnyEvent::Log::COLLECT->attach (
862	log_cb => sub { syswrite $fh, shift; 0 });	1214	new AnyEvent::Log::Ctx log_to_file => $path);
863		1215
		1216	PERL_ANYEVENT_LOG=%filelogger=file=/some/path:collect=+%filelogger
		1217
864	In both cases, messages are still written to STDOUT.	1218	In both cases, messages are still written to STDERR.
865		1219
866	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).	1220	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
867		1221
868	Attach the CyAnyEvent::Log::Default> context to the C<AnyEvent::Debug>	1222	Attach the C<$AnyEvent::Log::LOG> context to the C<AnyEvent::Debug>
869	context and increase the C<AnyEvent::Debug> logging level - this simply
870	circumvents the global filtering for trace messages.	1223	context - this simply circumvents the global filtering for trace messages.
871		1224
872	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;	1225	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
873	$debug->attach ($AnyEvent::Log::Default);	1226	$debug->attach ($AnyEvent::Log::LOG);
874	$debug->levels ("trace"); # not "level"!
875		1227
876	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.
877		1233
878	=back	1234	=back
879		1235
880	=head1 AUTHOR	1236	=head1 AUTHOR
881		1237
882	Marc Lehmann <schmorp@schmorp.de>	1238	Marc Lehmann <schmorp@schmorp.de>
883	http://home.schmorp.de/	1239	http://home.schmorp.de/
884		1240
885	=cut	1241	=cut
		1242

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents): Revision 1.15 by root, Sat Aug 20 02:16:59 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 1.15 by root, Sat Aug 20 02:16:59 2011 UTC vs.
Revision 1.36 by root, Thu Aug 25 05:39:47 2011 UTC