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

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.12 by root, Sat Aug 20 01:33:10 2011 UTC vs.
Revision 1.37 by root, Thu Aug 25 06:34:11 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
…		…
74		111
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 (); need to load this in a delayed fashion, as it uses AE::log
		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	$$renabled = 1; # TODO
305	}	348	}
306	}	349	}
307		350
308	sub _logger($;$) {	351	sub _logger {
309	my ($ctx, $level, $renabled) = @_;	352	my ($ctx, $level, $renabled) = @_;
310		353
311	$renabled \|\|= \my $enabled;
312
313	$$renabled = 1;	354	$$renabled = 1;
314		355
315	my $logger = [$ctx, $level, $renabled];	356	my $logger = [$ctx, $level, $renabled];
316		357
317	$LOGGER{$logger+0} = $logger;	358	$LOGGER{$logger+0} = $logger;
318		359
319	_reassess $logger+0;	360	_reassess $logger+0;
320		361
		362	require AnyEvent::Util;
321	my $guard = AnyEvent::Util::guard {	363	my $guard = AnyEvent::Util::guard (sub {
322	# "clean up"	364	# "clean up"
323	delete $LOGGER{$logger+0};	365	delete $LOGGER{$logger+0};
324	};	366	});
325		367
326	sub {	368	sub {
327	$guard if 0; # keep guard alive, but don't cause runtime overhead	369	$guard if 0; # keep guard alive, but don't cause runtime overhead
328		370
329	_log $ctx, $level, @_	371	_log $ctx, $level, @_
…		…
356	timestamp, context, level and string message and formats it in the way	398	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	399	it should be logged) and a logging callback (which is responsible for
358	actually logging the formatted message and telling C<AnyEvent::Log>	400	actually logging the formatted message and telling C<AnyEvent::Log>
359	whether it has consumed the message, or whether it should be propagated).	401	whether it has consumed the message, or whether it should be propagated).
360		402
361	For propagation, a context can have any number of attached I<parent	403	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	404	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	405	masked by the logging callback returning true will be passed to all slave
364	contexts.	406	contexts.
365		407
366	Each call to a logging function will log the message at most once per	408	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	409	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.	410	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	414	By default, all logging contexts have an full set of log levels ("all"), a
373	disabled logging callback and the default formatting callback.	415	disabled logging callback and the default formatting callback.
374		416
375	Package contexts have the package name as logging title by default.	417	Package contexts have the package name as logging title by default.
376		418
377	They have exactly one parent - the context of the "parent" package. The	419	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	420	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>,	421	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
380	and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the	422	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	423	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	424	package name in Perl is C<main>, the default slave of any top-level
383	C<AnyEvent::Log::Top>.	425	package context is C<$AnyEvent::Log::COLLECT>.
384		426
385	Since perl packages form only an approximate hierarchy, this parent	427	Since perl packages form only an approximate hierarchy, this slave
386	context can of course be removed.	428	context can of course be removed.
387		429
388	All other (anonymous) contexts have no parents and an empty title by	430	All other (anonymous) contexts have no slaves and an empty title by
389	default.	431	default.
390		432
391	When the module is loaded it creates the default context called	433	When the module is loaded it creates the C<$AnyEvent::Log::LOG> logging
392	C<AnyEvent::Log::Default> (also stored in C<$AnyEvent::Log::Default>),	434	context that simply logs everything via C<warn>, without propagating
393	which simply logs everything to STDERR and doesn't propagate anything
394	anywhere by default. The purpose of the default context is to provide	435	anything anywhere by default. The purpose of this context is to provide
395	a convenient place to override the global logging target or to attach	436	a convenient place to override the global logging target or to attach
396	additional log targets. It's not meant for filtering.	437	additional log targets. It's not meant for filtering.
397		438
398	It then creates the root context called C<AnyEvent::Log::Root> (also	439	It then creates the C<$AnyEvent::Log::FILTER> context whose
399	stored in C<$AnyEvent::Log::Root>) and sets its log level set to all	440	purpose is to suppress all messages with priority higher
400	levels up to the one specified by C<$ENV{PERL_ANYEVENT_VERBOSE}>. It	441	than C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the
401	then attached the default logging context to it. The purpose of the root	442	C<$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.	443	is to simply provide filtering according to some global log level.
403		444
404	Finally it creates the top-level package context called	445	Finally it creates the top-level package context C<$AnyEvent::Log::COLLECT>
405	C<AnyEvent::Log::Top> (also stored in, you might have guessed,	446	and attaches the C<$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	447	leaves it at default config. Its purpose is simply to collect all log
408	system-wide.	448	messages system-wide.
409		449
410	These three special contexts can also be referred to by the	450	The hierarchy is then:
411	package/context names C<AE::Log::Default>, C<AE::Log::Root> and
412	C<AE::Log::Top>.
413		451
		452	any package, eventually -> $COLLECT -> $FILTER -> $LOG
		453
414	The effect of all this is that log messages, by default, wander up	454	The effect of all this is that log messages, by default, wander up to the
415	to the root context where log messages with lower priority then	455	C<$AnyEvent::Log::COLLECT> context where all messages normally end up,
		456	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	457	priority then C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered out and then
417	AnyEvent::Log::Default context to be logged to STDERR.	458	to the C<$AnyEvent::Log::LOG> context to be passed to C<warn>.
418		459
419	Splitting the top level context into three contexts makes it easy to set	460	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	461	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	462	messages to the $LOG target despite the global logging level, or to attach
423	log targets that log messages, regardless of the global logging level.	463	additional log targets that log messages, regardless of the global logging
		464	level.
424		465
425	It also makes it easy to replace the default STDERR-logger by something	466	It also makes it easy to modify the default warn-logger ($LOG) to
426	that logs to a file, or to attach additional logging targets.	467	something that logs to a file, or to attach additional logging targets
		468	(such as loggign to a file) by attaching it to $FILTER.
427		469
428	=head2 CREATING/FINDING/DESTROYING CONTEXTS	470	=head2 CREATING/FINDING/DESTROYING CONTEXTS
429		471
430	=over 4	472	=over 4
431		473
…		…
453	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"	495	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"
454	}	496	}
455		497
456	=item AnyEvent::Log::reset	498	=item AnyEvent::Log::reset
457		499
458	Deletes all contexts and recreates the default hierarchy, i.e. resets the	500	Resets all package contexts and recreates the default hierarchy if
459	logging subsystem to defaults.	501	necessary, i.e. resets the logging subsystem to defaults, as much as
		502	possible. This process keeps references to contexts held by other parts of
		503	the program intact.
460		504
461	This can be used to implement config-file (re-)loading: before loading a	505	This can be used to implement config-file (re-)loading: before loading a
462	configuration, reset all contexts.	506	configuration, reset all contexts.
463		507
464	=cut	508	=cut
465		509
466	sub reset {	510	sub reset {
467	@$_ = () for values %CTX; # just to be sure - to kill circular logging dependencies	511	# hard to kill complex data structures
468	%CTX = ();	512	# we "recreate" all package loggers and reset the hierarchy
		513	while (my ($k, $v) = each %CTX) {
		514	@$v = ($k, (1 << 10) - 1 - 1, { });
469		515
470	my $default = ctx undef;	516	$v->attach ($k =~ /^(.+)::/ ? $CTX{$1} : $AnyEvent::Log::COLLECT);
471	$default->title ("AnyEvent::Log::Default");
472	$default->log_cb (sub {
473	print STDERR shift;
474	0
475	});	517	}
476	$AnyEvent::Log::Default = $CTX{"AnyEvent::Log::Default"} = $CTX{"AE::Log::Default"} = $default;
477		518
478	my $root = ctx undef;	519	@$_ = ($_->[0], (1 << 10) - 1 - 1)
		520	for $LOG, $FILTER, $COLLECT;
		521
		522	#$LOG->slaves;
479	$root->title ("AnyEvent::Log::Root");	523	$LOG->title ('$AnyEvent::Log::LOG');
		524	$LOG->log_to_warn;
		525
		526	$FILTER->slaves ($LOG);
		527	$FILTER->title ('$AnyEvent::Log::FILTER');
480	$root->level ($AnyEvent::VERBOSE);	528	$FILTER->level ($AnyEvent::VERBOSE);
481	$root->attach ($default);
482	$AnyEvent::Log::Root = $CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $root;
483		529
484	my $top = ctx undef;	530	$COLLECT->slaves ($FILTER);
485	$top->title ("AnyEvent::Log::Top");	531	$COLLECT->title ('$AnyEvent::Log::COLLECT');
486	$top->attach ($root);	532
487	$AnyEvent::Log::Top = $CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $top;	533	_reassess;
488	}	534	}
		535
		536	# create the default logger contexts
		537	$LOG = ctx undef;
		538	$FILTER = ctx undef;
		539	$COLLECT = ctx undef;
489		540
490	AnyEvent::Log::reset;	541	AnyEvent::Log::reset;
491		542
492	# hello, CPAN, please catch me	543	# hello, CPAN, please catch me
493	package AnyEvent::Log::Default;
494	package AE::Log::Default;
495	package AnyEvent::Log::Root;
496	package AE::Log::Root;
497	package AnyEvent::Log::Top;	544	package AnyEvent::Log::LOG;
498	package AE::Log::Top;	545	package AE::Log::LOG;
		546	package AnyEvent::Log::FILTER;
		547	package AE::Log::FILTER;
		548	package AnyEvent::Log::COLLECT;
		549	package AE::Log::COLLECT;
499		550
500	package AnyEvent::Log::Ctx;	551	package AnyEvent::Log::Ctx;
501		552
502	# 0 1 2 3 4	553	# 0 1 2 3 4
503	# [$title, $level, %$parents, &$logcb, &$fmtcb]	554	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
504		555
505	=item $ctx = new AnyEvent::Log::Ctx methodname => param...	556	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
506		557
507	This is a convenience constructor that makes it simpler to construct	558	This is a convenience constructor that makes it simpler to construct
508	anonymous logging contexts.	559	anonymous logging contexts.
…		…
511	name as the key with the value as parameter, unless the value is an	562	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	563	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.	564	array. The methods are called in the same order as specified.
514		565
515	Example: create a new logging context and set both the default logging	566	Example: create a new logging context and set both the default logging
516	level, some parent contexts and a logging callback.	567	level, some slave contexts and a logging callback.
517		568
518	$ctx = new AnyEvent::Log::Ctx	569	$ctx = new AnyEvent::Log::Ctx
519	title => "dubious messages",	570	title => "dubious messages",
520	level => "error",	571	level => "error",
521	log_cb => sub { print STDOUT shift; 0 },	572	log_cb => sub { print STDOUT shift; 0 },
522	parents => [$ctx1, $ctx, $ctx2],	573	slaves => [$ctx1, $ctx, $ctx2],
523	;	574	;
524		575
525	=back	576	=back
526		577
527	=cut	578	=cut
…		…
640	AnyEvent::Log::_reassess;	691	AnyEvent::Log::_reassess;
641	}	692	}
642		693
643	=back	694	=back
644		695
645	=head3 PARENT CONTEXTS	696	=head3 SLAVE CONTEXTS
646		697
647	The following methods attach and detach another logging context to a	698	The following methods attach and detach another logging context to a
648	logging context.	699	logging context.
649		700
650	Log messages are propagated to all parent contexts, unless the logging	701	Log messages are propagated to all slave contexts, unless the logging
651	callback consumes the message.	702	callback consumes the message.
652		703
653	=over 4	704	=over 4
654		705
655	=item $ctx->attach ($ctx2[, $ctx3...])	706	=item $ctx->attach ($ctx2[, $ctx3...])
656		707
657	Attaches the given contexts as parents to this context. It is not an error	708	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).	709	to add a context twice (the second add will be ignored).
659		710
660	A context can be specified either as package name or as a context object.	711	A context can be specified either as package name or as a context object.
661		712
662	=item $ctx->detach ($ctx2[, $ctx3...])	713	=item $ctx->detach ($ctx2[, $ctx3...])
663		714
664	Removes the given parents from this context - it's not an error to attempt	715	Removes the given slaves from this context - it's not an error to attempt
665	to remove a context that hasn't been added.	716	to remove a context that hasn't been added.
666		717
667	A context can be specified either as package name or as a context object.	718	A context can be specified either as package name or as a context object.
668		719
669	=item $ctx->parents ($ctx2[, $ctx3...])	720	=item $ctx->slaves ($ctx2[, $ctx3...])
670		721
671	Replaces all parents attached to this context by the ones given.	722	Replaces all slaves attached to this context by the ones given.
672		723
673	=cut	724	=cut
674		725
675	sub attach {	726	sub attach {
676	my $ctx = shift;	727	my $ctx = shift;
…		…
684		735
685	delete $ctx->[2]{$_+0}	736	delete $ctx->[2]{$_+0}
686	for map { AnyEvent::Log::ctx $_ } @_;	737	for map { AnyEvent::Log::ctx $_ } @_;
687	}	738	}
688		739
689	sub parents {	740	sub slaves {
690	undef $_[0][2];	741	undef $_[0][2];
691	&attach;	742	&attach;
692	}	743	}
693		744
694	=back	745	=back
695		746
696	=head3 MESSAGE LOGGING	747	=head3 LOG TARGETS
697		748
698	The following methods configure how the logging context actually does	749	The following methods configure how the logging context actually does
699	the logging (which consists of formatting the message and printing it or	750	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	751	whatever it wants to do with it).
701	directly to a context, without going via your package context.
702		752
703	=over 4	753	=over 4
704		754
705	=item $ctx->log_cb ($cb->($str))	755	=item $ctx->log_cb ($cb->($str)
706		756
707	Replaces the logging callback on the context (C<undef> disables the	757	Replaces the logging callback on the context (C<undef> disables the
708	logging callback).	758	logging callback).
709		759
710	The logging callback is responsible for handling formatted log messages	760	The logging callback is responsible for handling formatted log messages
711	(see C<fmt_cb> below) - normally simple text strings that end with a	761	(see C<fmt_cb> below) - normally simple text strings that end with a
712	newline (and are possibly multiline themselves).	762	newline (and are possibly multiline themselves).
713		763
714	It also has to return true iff it has consumed the log message, and false	764	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	765	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.	766	slave context. When in doubt, return C<0> from your logging callback.
717		767
718	Example: a very simple logging callback, simply dump the message to STDOUT	768	Example: a very simple logging callback, simply dump the message to STDOUT
719	and do not consume it.	769	and do not consume it.
720		770
721	$ctx->log_cb (sub { print STDERR shift; 0 });	771	$ctx->log_cb (sub { print STDERR shift; 0 });
…		…
729	your program.	779	your program.
730		780
731	$ctx->levels ("debug", "trace");	781	$ctx->levels ("debug", "trace");
732	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages	782	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages
733		783
734	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	784	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $orig_ctx, $level, $message))
735		785
736	Replaces the formatting callback on the context (C<undef> restores the	786	Replaces the formatting callback on the context (C<undef> restores the
737	default formatter).	787	default formatter).
738		788
739	The callback is passed the (possibly fractional) timestamp, the original	789	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	790	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	791	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.	792	string, but it could just as well be an array reference that just stores
		793	the values.
		794
		795	If, for some reason, you want to use C<caller> to find out more baout the
		796	logger then you should walk up the call stack until you are no longer
		797	inside the C<AnyEvent::Log> package.
743		798
744	Example: format just the raw message, with numeric log level in angle	799	Example: format just the raw message, with numeric log level in angle
745	brackets.	800	brackets.
746		801
747	$ctx->fmt_cb (sub {	802	$ctx->fmt_cb (sub {
…		…
764	"$msg->[3]";	819	"$msg->[3]";
765		820
766	0	821	0
767	});	822	});
768		823
		824	=item $ctx->log_to_warn
		825
		826	Sets the C<log_cb> to simply use C<CORE::warn> to report any messages
		827	(usually this logs to STDERR).
		828
		829	=item $ctx->log_to_file ($path)
		830
		831	Sets the C<log_cb> to log to a file (by appending), unbuffered.
		832
		833	=item $ctx->log_to_path ($path)
		834
		835	Same as C<< ->log_to_file >>, but opens the file for each message. This
		836	is much slower, but allows you to change/move/rename/delete the file at
		837	basically any time.
		838
		839	Needless(?) to say, if you do not want to be bitten by some evil person
		840	calling C<chdir>, the path should be absolute. Doesn't help with
		841	C<chroot>, but hey...
		842
		843	=item $ctx->log_to_syslog ([$log_flags])
		844
		845	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and all
		846	the others in the obvious way. If specified, then the C<$log_flags> are
		847	simply or'ed onto the priority argument and can contain any C<LOG_xxx>
		848	flags valid for Sys::Syslog::syslog, except for the priority levels.
		849
		850	Note that this function also sets a C<fmt_cb> - the logging part requires
		851	an array reference with [$level, $str] as input.
		852
769	=cut	853	=cut
770		854
771	sub log_cb {	855	sub log_cb {
772	my ($ctx, $cb) = @_;	856	my ($ctx, $cb) = @_;
773		857
…		…
778	my ($ctx, $cb) = @_;	862	my ($ctx, $cb) = @_;
779		863
780	$ctx->[4] = $cb;	864	$ctx->[4] = $cb;
781	}	865	}
782		866
783	=item $ctx->log ($level, $msg[, @params])	867	sub log_to_warn {
		868	my ($ctx, $path) = @_;
784		869
785	Same as C<AnyEvent::Log::log>, but uses the given context as log context.	870	$ctx->log_cb (sub {
		871	warn shift;
		872	0
		873	});
		874	}
786		875
787	=item $logger = $ctx->logger ($level[, \$enabled])	876	sub log_to_file {
788		877	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		878
820	open my $fh, ">>", $path	879	open my $fh, ">>", $path
821	or die "$path: $!";	880	or die "$path: $!";
822		881
823	$AnyEvent::Log::Default->log_cb (sub {	882	$ctx->log_cb (sub {
824	syswrite $fh, shift;	883	syswrite $fh, shift;
825	0	884	0
826	});	885	});
		886	}
		887
		888	sub log_to_path {
		889	my ($ctx, $path) = @_;
		890
		891	$ctx->log_cb (sub {
		892	open my $fh, ">>", $path
		893	or die "$path: $!";
		894
		895	syswrite $fh, shift;
		896	0
		897	});
		898	}
		899
		900	sub log_to_syslog {
		901	my ($ctx, $flags) = @_;
		902
		903	require Sys::Syslog;
		904
		905	$ctx->fmt_cb (sub {
		906	my $str = $_[3];
		907	$str =~ s/\n(?=.)/\n+ /g;
		908
		909	[$_[2], "($_[1][0]) $str"]
		910	});
		911
		912	$ctx->log_cb (sub {
		913	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;
		914
		915	Sys::Syslog::syslog ($flags \| ($lvl - 1), $_)
		916	for split /\n/, $_[0][1];
		917
		918	0
		919	});
		920	}
		921
		922	=back
		923
		924	=head3 MESSAGE LOGGING
		925
		926	These methods allow you to log messages directly to a context, without
		927	going via your package context.
		928
		929	=over 4
		930
		931	=item $ctx->log ($level, $msg[, @params])
		932
		933	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
		934
		935	=item $logger = $ctx->logger ($level[, \$enabled])
		936
		937	Same as C<AnyEvent::Log::logger>, but uses the given context as log
		938	context.
		939
		940	=cut
		941
		942	*log = \&AnyEvent::Log::_log;
		943	*logger = \&AnyEvent::Log::_logger;
		944
		945	=back
		946
		947	=cut
		948
		949	package AnyEvent::Log;
		950
		951	=head1 CONFIGURATION VIA $ENV{PERL_ANYEVENT_LOG}
		952
		953	Logging can also be configured by setting the environment variable
		954	C<PERL_ANYEVENT_LOG> (or C<AE_LOG>).
		955
		956	The value consists of one or more logging context specifications separated
		957	by C<:> or whitespace. Each logging specification in turn starts with a
		958	context name, followed by C<=>, followed by zero or more comma-separated
		959	configuration directives, here are some examples:
		960
		961	# set default logging level
		962	filter=warn
		963
		964	# log to file instead of to stderr
		965	log=file=/tmp/mylog
		966
		967	# log to file in addition to stderr
		968	log=+%file:%file=file=/tmp/mylog
		969
		970	# enable debug log messages, log warnings and above to syslog
		971	filter=debug:log=+%warnings:%warnings=warn,syslog=LOG_LOCAL0
		972
		973	# log trace messages (only) from AnyEvent::Debug to file
		974	AnyEvent::Debug=+%trace:%trace=only,trace,file=/tmp/tracelog
		975
		976	A context name in the log specification can be any of the following:
		977
		978	=over 4
		979
		980	=item C<collect>, C<filter>, C<log>
		981
		982	Correspond to the three predefined C<$AnyEvent::Log::COLLECT>,
		983	C<AnyEvent::Log::FILTER> and C<$AnyEvent::Log::LOG> contexts.
		984
		985	=item C<%name>
		986
		987	Context names starting with a C<%> are anonymous contexts created when the
		988	name is first mentioned. The difference to package contexts is that by
		989	default they have no attached slaves.
		990
		991	=item a perl package name
		992
		993	Any other string references the logging context associated with the given
		994	Perl C<package>. In the unlikely case where you want to specify a package
		995	context that matches on of the other context name forms, you can add a
		996	C<::> to the package name to force interpretation as a package.
		997
		998	=back
		999
		1000	The configuration specifications can be any number of the following:
		1001
		1002	=over 4
		1003
		1004	=item C<stderr>
		1005
		1006	Configures the context to use Perl's C<warn> function (which typically
		1007	logs to C<STDERR>). Works like C<log_to_warn>.
		1008
		1009	=item C<file=>I<path>
		1010
		1011	Configures the context to log to a file with the given path. Works like
		1012	C<log_to_file>.
		1013
		1014	=item C<path=>I<path>
		1015
		1016	Configures the context to log to a file with the given path. Works like
		1017	C<log_to_path>.
		1018
		1019	=item C<syslog> or C<syslog=>I<expr>
		1020
		1021	Configures the context to log to syslog. If I<expr> is given, then it is
		1022	evaluated in the L<Sys::Syslog> package, so you could use:
		1023
		1024	log=syslog=LOG_LOCAL0
		1025
		1026	=item C<nolog>
		1027
		1028	Configures the context to not log anything by itself, which is the
		1029	default. Same as C<< $ctx->log_cb (undef) >>.
		1030
		1031	=item C<0> or C<off>
		1032
		1033	Sets the logging level of the context ot C<0>, i.e. all messages will be
		1034	filtered out.
		1035
		1036	=item C<all>
		1037
		1038	Enables all logging levels, i.e. filtering will effectively be switched
		1039	off (the default).
		1040
		1041	=item C<only>
		1042
		1043	Disables all logging levels, and changes the interpretation of following
		1044	level specifications to enable the specified level only.
		1045
		1046	Example: only enable debug messages for a context.
		1047
		1048	context=only,debug
		1049
		1050	=item C<except>
		1051
		1052	Enables all logging levels, and changes the interpretation of following
		1053	level specifications to disable that level. Rarely used.
		1054
		1055	Example: enable all logging levels except fatal and trace (this is rather
		1056	nonsensical).
		1057
		1058	filter=exept,fatal,trace
		1059
		1060	=item C<level>
		1061
		1062	Enables all logging levels, and changes the interpretation of following
		1063	level specifications to be "that level or any higher priority
		1064	message". This is the default.
		1065
		1066	Example: log anything at or above warn level.
		1067
		1068	filter=warn
		1069
		1070	# or, more verbose
		1071	filter=only,level,warn
		1072
		1073	=item C<1>..C<9> or a logging level name (C<error>, C<debug> etc.)
		1074
		1075	A numeric loglevel or the name of a loglevel will be interpreted according
		1076	to the most recent C<only>, C<except> or C<level> directive. By default,
		1077	specifying a logging level enables that and any higher priority messages.
		1078
		1079	=item C<+>I<context>
		1080
		1081	Attaches the named context as slave to the context.
		1082
		1083	=item C<+>
		1084
		1085	A line C<+> detaches all contexts, i.e. clears the slave list from the
		1086	context. Anonymous (C<%name>) contexts have no attached slaves by default,
		1087	but package contexts have the parent context as slave by default.
		1088
		1089	Example: log messages from My::Module to a file, do not send them to the
		1090	default log collector.
		1091
		1092	My::Module=+,file=/tmp/mymodulelog
		1093
		1094	=back
		1095
		1096	Any character can be escaped by prefixing it with a C<\> (backslash), as
		1097	usual, so to log to a file containing a comma, colon, backslash and some
		1098	spaces in the filename, you would do this:
		1099
		1100	PERL_ANYEVENT_LOG='log=file=/some\ \:file\ with\,\ \\-escapes'
		1101
		1102	Since whitespace (which includes newlines) is allowed, it is fine to
		1103	specify multiple lines in C<PERL_ANYEVENT_LOG>, e.g.:
		1104
		1105	PERL_ANYEVENT_LOG="
		1106	filter=warn
		1107	AnyEvent::Debug=+%trace
		1108	%trace=only,trace,+log
		1109	" myprog
		1110
		1111	Also, in the unlikely case when you want to concatenate specifications,
		1112	use whitespace as separator, as C<::> will be interpreted as part of a
		1113	module name, an empty spec with two separators:
		1114
		1115	PERL_ANYEVENT_LOG="$PERL_ANYEVENT_LOG MyMod=debug"
		1116
		1117	=cut
		1118
		1119	for (my $spec = $ENV{PERL_ANYEVENT_LOG}) {
		1120	my %anon;
		1121
		1122	my $pkg = sub {
		1123	$_[0] eq "log" ? $LOG
		1124	: $_[0] eq "filter" ? $FILTER
		1125	: $_[0] eq "collect" ? $COLLECT
		1126	: $_[0] =~ /^%(.+)$/ ? ($anon{$1} \|\|= ctx undef)
		1127	: $_[0] =~ /^(.*?)(?:::)?$/ ? ctx "$1" # egad :/
		1128	: die # never reached?
		1129	};
		1130
		1131	/\G[[:space:]]+/gc; # skip initial whitespace
		1132
		1133	while (/\G((?:[^:=[:space:]]+\|::\|\\.)+)=/gc) {
		1134	my $ctx = $pkg->($1);
		1135	my $level = "level";
		1136
		1137	while (/\G((?:[^,:[:space:]]+\|::\|\\.)+)/gc) {
		1138	for ("$1") {
		1139	if ($_ eq "stderr" ) { $ctx->log_to_warn;
		1140	} elsif (/^file=(.+)/ ) { $ctx->log_to_file ("$1");
		1141	} elsif (/^path=(.+)/ ) { $ctx->log_to_path ("$1");
		1142	} elsif (/syslog(?:=(.*))?/ ) { require Sys::Syslog; $ctx->log_to_syslog (eval "package Sys::Syslog; $1");
		1143	} elsif ($_ eq "nolog" ) { $ctx->log_cb (undef);
		1144	} elsif (/^\+(.+)$/ ) { $ctx->attach ($pkg->("$1"));
		1145	} elsif ($_ eq "+" ) { $ctx->slaves;
		1146	} elsif ($_ eq "off" or $_ eq "0") { $ctx->level (0);
		1147	} elsif ($_ eq "all" ) { $ctx->level ("all");
		1148	} elsif ($_ eq "level" ) { $ctx->level ("all"); $level = "level";
		1149	} elsif ($_ eq "only" ) { $ctx->level ("off"); $level = "enable";
		1150	} elsif ($_ eq "except" ) { $ctx->level ("all"); $level = "disable";
		1151	} elsif (/^\d$/ ) { $ctx->$level ($_);
		1152	} elsif (exists $STR2LEVEL{$_} ) { $ctx->$level ($_);
		1153	} else { die "PERL_ANYEVENT_LOG ($spec): parse error at '$_'\n";
		1154	}
		1155	}
		1156
		1157	/\G,/gc or last;
		1158	}
		1159
		1160	/\G[:[:space:]]+/gc or last;
		1161	}
		1162
		1163	/\G[[:space:]]+/gc; # skip trailing whitespace
		1164
		1165	if (/\G(.+)/g) {
		1166	die "PERL_ANYEVENT_LOG ($spec): parse error at '$1'\n";
		1167	}
		1168	}
		1169
		1170	1;
		1171
		1172	=head1 EXAMPLES
		1173
		1174	This section shows some common configurations, both as code, and as
		1175	C<PERL_ANYEVENT_LOG> string.
		1176
		1177	=over 4
		1178
		1179	=item Setting the global logging level.
		1180
		1181	Either put C<PERL_ANYEVENT_VERBOSE=><number> into your environment before
		1182	running your program, use C<PERL_ANYEVENT_LOG> or modify the log level of
		1183	the root context at runtime:
		1184
		1185	PERL_ANYEVENT_VERBOSE=5 ./myprog
		1186
		1187	PERL_ANYEVENT_LOG=log=warn
		1188
		1189	$AnyEvent::Log::FILTER->level ("warn");
		1190
		1191	=item Append all messages to a file instead of sending them to STDERR.
		1192
		1193	This is affected by the global logging level.
		1194
		1195	$AnyEvent::Log::LOG->log_to_file ($path);
		1196
		1197	PERL_ANYEVENT_LOG=log=file=/some/path
827		1198
828	=item Write all messages with priority C<error> and higher to a file.	1199	=item Write all messages with priority C<error> and higher to a file.
829		1200
830	This writes them only when the global logging level allows it, because	1201	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	1202	it is attached to the default context which is invoked I<after> global
832	filtering.	1203	filtering.
833		1204
834	open my $fh, ">>", $path	1205	$AnyEvent::Log::FILTER->attach
835	or die "$path: $!";	1206	new AnyEvent::Log::Ctx log_to_file => $path);
836		1207
837	$AnyEvent::Log::Default->attach (new AnyEvent::Log::Ctx	1208	PERL_ANYEVENT_LOG=filter=+%filelogger:%filelogger=file=/some/path
838	log_cb => sub { syswrite $fh, shift; 0 });
839		1209
840	This writes them regardless of the global logging level, because it is	1210	This writes them regardless of the global logging level, because it is
841	attached to the toplevel context, which receives all messages I<before>	1211	attached to the toplevel context, which receives all messages I<before>
842	the global filtering.	1212	the global filtering.
843		1213
844	$AnyEvent::Log::Top->attach (new AnyEvent::Log::Ctx	1214	$AnyEvent::Log::COLLECT->attach (
845	log_cb => sub { syswrite $fh, shift; 0 });	1215	new AnyEvent::Log::Ctx log_to_file => $path);
846		1216
		1217	PERL_ANYEVENT_LOG=%filelogger=file=/some/path:collect=+%filelogger
		1218
847	In both cases, messages are still written to STDOUT.	1219	In both cases, messages are still written to STDERR.
848		1220
849	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).	1221	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
850		1222
851	Attach the CyAnyEvent::Log::Default> context to the C<AnyEvent::Debug>	1223	Attach the C<$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.	1224	context - this simply circumvents the global filtering for trace messages.
854		1225
855	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;	1226	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
856	$debug->attach ($AnyEvent::Log::Default);	1227	$debug->attach ($AnyEvent::Log::LOG);
857	$debug->levels ("trace"); # not "level"!	1228
		1229	PERL_ANYEVENT_LOG=AnyEvent::Debug=+log
		1230
		1231	This of course works for any package, not just L<AnyEvent::Debug>, but
		1232	assumes the log level for AnyEvent::Debug hasn't been changed from the
		1233	default.
858		1234
859	=back	1235	=back
860		1236
861	=head1 AUTHOR	1237	=head1 AUTHOR
862		1238
863	Marc Lehmann <schmorp@schmorp.de>	1239	Marc Lehmann <schmorp@schmorp.de>
864	http://home.schmorp.de/	1240	http://home.schmorp.de/
865		1241
866	=cut	1242	=cut
		1243

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents): Revision 1.12 by root, Sat Aug 20 01:33:10 2011 UTC vs. Revision 1.37 by root, Thu Aug 25 06:34:11 2011 UTC

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.12 by root, Sat Aug 20 01:33:10 2011 UTC vs.
Revision 1.37 by root, Thu Aug 25 06:34:11 2011 UTC