[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 1.38 by root, Fri Aug 26 00:32:45 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,
166	);	209	);
167		210
168	sub now () { time }	211	our $TIME_EXACT;
		212
		213	sub exact_time($) {
		214	$TIME_EXACT = shift;
		215	*_ts = $AnyEvent::MODEL
		216	? $TIME_EXACT ? \&AE::now : \&AE::time
		217	: sub () { $TIME_EXACT ? do { require Time::HiRes; Time::HiRes::time () } : time };
		218	}
		219
		220	BEGIN {
		221	exact_time 0;
		222	}
169		223
170	AnyEvent::post_detect {	224	AnyEvent::post_detect {
171	*now = \&AE::now;	225	exact_time $TIME_EXACT;
172	};	226	};
173		227
174	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);	228	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);
175		229
176	# time, ctx, level, msg	230	# time, ctx, level, msg
…		…
195	? $level+0	249	? $level+0
196	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";	250	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";
197		251
198	my $mask = 1 << $level;	252	my $mask = 1 << $level;
199		253
200	my (%seen, @ctx, $now, $fmt);	254	my ($success, %seen, @ctx, $now, $fmt);
201		255
202	do	256	do
203	{	257	{
204	# skip if masked	258	# skip if masked
205	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {	259	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {
…		…
209	# now get raw message, unless we have it already	263	# now get raw message, unless we have it already
210	unless ($now) {	264	unless ($now) {
211	$format = $format->() if ref $format;	265	$format = $format->() if ref $format;
212	$format = sprintf $format, @args if @args;	266	$format = sprintf $format, @args if @args;
213	$format =~ s/\n$//;	267	$format =~ s/\n$//;
214	$now = AE::now;	268	$now = _ts;
215	};	269	};
216		270
217	# format msg	271	# format msg
218	my $str = $ctx->[4]	272	my $str = $ctx->[4]
219	? $ctx->[4]($now, $_[0], $level, $format)	273	? $ctx->[4]($now, $_[0], $level, $format)
220	: $fmt \|\|= _format $now, $_[0], $level, $format;	274	: ($fmt \|\|= _format $now, $_[0], $level, $format);
221		275
		276	$success = 1;
		277
222	$ctx->[3]($str);	278	$ctx->[3]($str)
		279	or push @ctx, values %{ $ctx->[2] }; # not consumed - propagate
		280	} else {
		281	push @ctx, values %{ $ctx->[2] }; # not masked - propagate
223	}	282	}
224
225	# not masked, not consumed - propagate to parent contexts
226	push @ctx, values %{ $ctx->[2] };
227	}	283	}
228	}	284	}
229	while $ctx = pop @ctx;	285	while $ctx = pop @ctx;
230		286
231	exit 1 if $level <= 1;	287	exit 1 if $level <= 1;
		288
		289	$success
232	}	290	}
233		291
234	sub log($$;@) {	292	sub log($$;@) {
235	_log	293	_log
236	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	294	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
…		…
240	AnyEvent::log = AE::log = \&log;	298	AnyEvent::log = AE::log = \&log;
241		299
242	=item $logger = AnyEvent::Log::logger $level[, \$enabled]	300	=item $logger = AnyEvent::Log::logger $level[, \$enabled]
243		301
244	Creates a code reference that, when called, acts as if the	302	Creates a code reference that, when called, acts as if the
245	C<AnyEvent::Log::log> function was called at this point with the givne	303	C<AnyEvent::Log::log> function was called at this point with the given
246	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with	304	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with
247	the C<AnyEvent::Log::log> function:	305	the C<AnyEvent::Log::log> function:
248		306
249	my $debug_log = AnyEvent::Log::logger "debug";	307	my $debug_log = AnyEvent::Log::logger "debug";
250		308
…		…
275	# and later in your program	333	# and later in your program
276	$debug_log->("yo, stuff here") if $debug;	334	$debug_log->("yo, stuff here") if $debug;
277		335
278	$debug and $debug_log->("123");	336	$debug and $debug_log->("123");
279		337
280	Note: currently the enabled var is always true - that will be fixed in a
281	future version :)
282
283	=cut	338	=cut
284		339
285	our %LOGGER;	340	our %LOGGER;
286		341
287	# re-assess logging status for all loggers	342	# re-assess logging status for all loggers
288	sub _reassess {	343	sub _reassess {
		344	local $SIG{__DIE__};
		345	my $die = sub { die };
		346
289	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {	347	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {
290	my ($ctx, $level, $renabled) = @$_;	348	my ($ctx, $level, $renabled) = @$_;
291		349
292	# to detect whether a message would be logged, we # actually	350	# 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	351	# try to log one and die. this isn't fast, but we can be
294	# sure that the logging decision is correct :)	352	# sure that the logging decision is correct :)
295		353
296	$$renabled = !eval {	354	$$renabled = !eval {
297	local $SIG{__DIE__};
298
299	_log $ctx, $level, sub { die };	355	_log $ctx, $level, $die;
300		356
301	1	357	1
302	};	358	};
303
304	$$renabled = 1; # TODO
305	}	359	}
306	}	360	}
307		361
308	sub _logger($;$) {	362	sub _logger {
309	my ($ctx, $level, $renabled) = @_;	363	my ($ctx, $level, $renabled) = @_;
310		364
311	$renabled \|\|= \my $enabled;
312
313	$$renabled = 1;	365	$$renabled = 1;
314		366
315	my $logger = [$ctx, $level, $renabled];	367	my $logger = [$ctx, $level, $renabled];
316		368
317	$LOGGER{$logger+0} = $logger;	369	$LOGGER{$logger+0} = $logger;
318		370
319	_reassess $logger+0;	371	_reassess $logger+0;
320		372
		373	require AnyEvent::Util;
321	my $guard = AnyEvent::Util::guard {	374	my $guard = AnyEvent::Util::guard (sub {
322	# "clean up"	375	# "clean up"
323	delete $LOGGER{$logger+0};	376	delete $LOGGER{$logger+0};
324	};	377	});
325		378
326	sub {	379	sub {
327	$guard if 0; # keep guard alive, but don't cause runtime overhead	380	$guard if 0; # keep guard alive, but don't cause runtime overhead
328		381
329	_log $ctx, $level, @_	382	_log $ctx, $level, @_
…		…
334	sub logger($;$) {	387	sub logger($;$) {
335	_logger	388	_logger
336	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	389	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
337	@_	390	@_
338	}	391	}
		392
		393	=item AnyEvent::Log::exact_time $on
		394
		395	By default, C<AnyEvent::Log> will use C<AE::now>, i.e. the cached
		396	eventloop time, for the log timestamps. After calling this function with a
		397	true value it will instead resort to C<AE::time>, i.e. fetch the current
		398	time on each log message. This only makes a difference for event loops
		399	that actually cache the time (such as L<EV> or L<AnyEvent::Loop>).
		400
		401	Since C<AnyEvent::Log> has to work even before the L<AnyEvent> has been
		402	initialised, this switch will also decide whether to use C<CORE::time> or
		403	C<Time::HiRes::time> when logging a message before L<AnyEvent> becomes
		404	available.
339		405
340	=back	406	=back
341		407
342	=head1 LOGGING CONTEXTS	408	=head1 LOGGING CONTEXTS
343		409
…		…
356	timestamp, context, level and string message and formats it in the way	422	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	423	it should be logged) and a logging callback (which is responsible for
358	actually logging the formatted message and telling C<AnyEvent::Log>	424	actually logging the formatted message and telling C<AnyEvent::Log>
359	whether it has consumed the message, or whether it should be propagated).	425	whether it has consumed the message, or whether it should be propagated).
360		426
361	For propagation, a context can have any number of attached I<parent	427	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	428	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	429	masked by the logging callback returning true will be passed to all slave
364	contexts.	430	contexts.
365		431
366	Each call to a logging function will log the message at most once per	432	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	433	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.	434	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	438	By default, all logging contexts have an full set of log levels ("all"), a
373	disabled logging callback and the default formatting callback.	439	disabled logging callback and the default formatting callback.
374		440
375	Package contexts have the package name as logging title by default.	441	Package contexts have the package name as logging title by default.
376		442
377	They have exactly one parent - the context of the "parent" package. The	443	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	444	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>,	445	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
380	and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the	446	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	447	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	448	package name in Perl is C<main>, the default slave of any top-level
383	C<AnyEvent::Log::Top>.	449	package context is C<$AnyEvent::Log::COLLECT>.
384		450
385	Since perl packages form only an approximate hierarchy, this parent	451	Since perl packages form only an approximate hierarchy, this slave
386	context can of course be removed.	452	context can of course be removed.
387		453
388	All other (anonymous) contexts have no parents and an empty title by	454	All other (anonymous) contexts have no slaves and an empty title by
389	default.	455	default.
390		456
391	When the module is loaded it creates the default context called	457	When the module is loaded it creates the C<$AnyEvent::Log::LOG> logging
392	C<AnyEvent::Log::Default> (also stored in C<$AnyEvent::Log::Default>),	458	context that simply logs everything via C<warn>, without propagating
393	which simply logs everything to STDERR and doesn't propagate anything
394	anywhere by default. The purpose of the default context is to provide	459	anything anywhere by default. The purpose of this context is to provide
395	a convenient place to override the global logging target or to attach	460	a convenient place to override the global logging target or to attach
396	additional log targets. It's not meant for filtering.	461	additional log targets. It's not meant for filtering.
397		462
398	It then creates the root context called C<AnyEvent::Log::Root> (also	463	It then creates the C<$AnyEvent::Log::FILTER> context whose
399	stored in C<$AnyEvent::Log::Root>) and sets its log level set to all	464	purpose is to suppress all messages with priority higher
400	levels up to the one specified by C<$ENV{PERL_ANYEVENT_VERBOSE}>. It	465	than C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the
401	then attached the default logging context to it. The purpose of the root	466	C<$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.	467	is to simply provide filtering according to some global log level.
403		468
404	Finally it creates the top-level package context called	469	Finally it creates the top-level package context C<$AnyEvent::Log::COLLECT>
405	C<AnyEvent::Log::Top> (also stored in, you might have guessed,	470	and attaches the C<$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	471	leaves it at default config. Its purpose is simply to collect all log
408	system-wide.	472	messages system-wide.
409		473
410	These three special contexts can also be referred to by the	474	The hierarchy is then:
411	package/context names C<AE::Log::Default>, C<AE::Log::Root> and
412	C<AE::Log::Top>.
413		475
		476	any package, eventually -> $COLLECT -> $FILTER -> $LOG
		477
414	The effect of all this is that log messages, by default, wander up	478	The effect of all this is that log messages, by default, wander up to the
415	to the root context where log messages with lower priority then	479	C<$AnyEvent::Log::COLLECT> context where all messages normally end up,
		480	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	481	priority then C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered out and then
417	AnyEvent::Log::Default context to be logged to STDERR.	482	to the C<$AnyEvent::Log::LOG> context to be passed to C<warn>.
418		483
419	Splitting the top level context into three contexts makes it easy to set	484	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	485	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	486	messages to the $LOG target despite the global logging level, or to attach
423	log targets that log messages, regardless of the global logging level.	487	additional log targets that log messages, regardless of the global logging
		488	level.
424		489
425	It also makes it easy to replace the default STDERR-logger by something	490	It also makes it easy to modify the default warn-logger ($LOG) to
426	that logs to a file, or to attach additional logging targets.	491	something that logs to a file, or to attach additional logging targets
		492	(such as loggign to a file) by attaching it to $FILTER.
427		493
428	=head2 CREATING/FINDING/DESTROYING CONTEXTS	494	=head2 CREATING/FINDING/DESTROYING CONTEXTS
429		495
430	=over 4	496	=over 4
431		497
…		…
453	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"	519	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"
454	}	520	}
455		521
456	=item AnyEvent::Log::reset	522	=item AnyEvent::Log::reset
457		523
458	Deletes all contexts and recreates the default hierarchy, i.e. resets the	524	Resets all package contexts and recreates the default hierarchy if
459	logging subsystem to defaults.	525	necessary, i.e. resets the logging subsystem to defaults, as much as
		526	possible. This process keeps references to contexts held by other parts of
		527	the program intact.
460		528
461	This can be used to implement config-file (re-)loading: before loading a	529	This can be used to implement config-file (re-)loading: before loading a
462	configuration, reset all contexts.	530	configuration, reset all contexts.
463		531
464	=cut	532	=cut
465		533
466	sub reset {	534	sub reset {
467	@$_ = () for values %CTX; # just to be sure - to kill circular logging dependencies	535	# hard to kill complex data structures
468	%CTX = ();	536	# we "recreate" all package loggers and reset the hierarchy
		537	while (my ($k, $v) = each %CTX) {
		538	@$v = ($k, (1 << 10) - 1 - 1, { });
469		539
470	my $default = ctx undef;	540	$v->attach ($k =~ /^(.+)::/ ? $CTX{$1} : $AnyEvent::Log::COLLECT);
471	$default->title ("AnyEvent::Log::Default");
472	$default->log_cb (sub {
473	print STDERR shift;
474	0
475	});	541	}
476	$AnyEvent::Log::Default = $CTX{"AnyEvent::Log::Default"} = $CTX{"AE::Log::Default"} = $default;
477		542
478	my $root = ctx undef;	543	@$_ = ($_->[0], (1 << 10) - 1 - 1)
		544	for $LOG, $FILTER, $COLLECT;
		545
		546	#$LOG->slaves;
479	$root->title ("AnyEvent::Log::Root");	547	$LOG->title ('$AnyEvent::Log::LOG');
		548	$LOG->log_to_warn;
		549
		550	$FILTER->slaves ($LOG);
		551	$FILTER->title ('$AnyEvent::Log::FILTER');
480	$root->level ($AnyEvent::VERBOSE);	552	$FILTER->level ($AnyEvent::VERBOSE);
481	$root->attach ($default);
482	$AnyEvent::Log::Root = $CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $root;
483		553
484	my $top = ctx undef;	554	$COLLECT->slaves ($FILTER);
485	$top->title ("AnyEvent::Log::Top");	555	$COLLECT->title ('$AnyEvent::Log::COLLECT');
486	$top->attach ($root);	556
487	$AnyEvent::Log::Top = $CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $top;	557	_reassess;
488	}	558	}
		559
		560	# create the default logger contexts
		561	$LOG = ctx undef;
		562	$FILTER = ctx undef;
		563	$COLLECT = ctx undef;
489		564
490	AnyEvent::Log::reset;	565	AnyEvent::Log::reset;
491		566
492	# hello, CPAN, please catch me	567	# hello, CPAN, please catch me
493	package AnyEvent::Log::Default;
494	package AE::Log::Default;
495	package AnyEvent::Log::Root;
496	package AE::Log::Root;
497	package AnyEvent::Log::Top;	568	package AnyEvent::Log::LOG;
498	package AE::Log::Top;	569	package AE::Log::LOG;
		570	package AnyEvent::Log::FILTER;
		571	package AE::Log::FILTER;
		572	package AnyEvent::Log::COLLECT;
		573	package AE::Log::COLLECT;
499		574
500	package AnyEvent::Log::Ctx;	575	package AnyEvent::Log::Ctx;
501		576
502	# 0 1 2 3 4	577	# 0 1 2 3 4
503	# [$title, $level, %$parents, &$logcb, &$fmtcb]	578	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
504		579
505	=item $ctx = new AnyEvent::Log::Ctx methodname => param...	580	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
506		581
507	This is a convenience constructor that makes it simpler to construct	582	This is a convenience constructor that makes it simpler to construct
508	anonymous logging contexts.	583	anonymous logging contexts.
…		…
511	name as the key with the value as parameter, unless the value is an	586	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	587	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.	588	array. The methods are called in the same order as specified.
514		589
515	Example: create a new logging context and set both the default logging	590	Example: create a new logging context and set both the default logging
516	level, some parent contexts and a logging callback.	591	level, some slave contexts and a logging callback.
517		592
518	$ctx = new AnyEvent::Log::Ctx	593	$ctx = new AnyEvent::Log::Ctx
519	title => "dubious messages",	594	title => "dubious messages",
520	level => "error",	595	level => "error",
521	log_cb => sub { print STDOUT shift; 0 },	596	log_cb => sub { print STDOUT shift; 0 },
522	parents => [$ctx1, $ctx, $ctx2],	597	slaves => [$ctx1, $ctx, $ctx2],
523	;	598	;
524		599
525	=back	600	=back
526		601
527	=cut	602	=cut
…		…
640	AnyEvent::Log::_reassess;	715	AnyEvent::Log::_reassess;
641	}	716	}
642		717
643	=back	718	=back
644		719
645	=head3 PARENT CONTEXTS	720	=head3 SLAVE CONTEXTS
646		721
647	The following methods attach and detach another logging context to a	722	The following methods attach and detach another logging context to a
648	logging context.	723	logging context.
649		724
650	Log messages are propagated to all parent contexts, unless the logging	725	Log messages are propagated to all slave contexts, unless the logging
651	callback consumes the message.	726	callback consumes the message.
652		727
653	=over 4	728	=over 4
654		729
655	=item $ctx->attach ($ctx2[, $ctx3...])	730	=item $ctx->attach ($ctx2[, $ctx3...])
656		731
657	Attaches the given contexts as parents to this context. It is not an error	732	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).	733	to add a context twice (the second add will be ignored).
659		734
660	A context can be specified either as package name or as a context object.	735	A context can be specified either as package name or as a context object.
661		736
662	=item $ctx->detach ($ctx2[, $ctx3...])	737	=item $ctx->detach ($ctx2[, $ctx3...])
663		738
664	Removes the given parents from this context - it's not an error to attempt	739	Removes the given slaves from this context - it's not an error to attempt
665	to remove a context that hasn't been added.	740	to remove a context that hasn't been added.
666		741
667	A context can be specified either as package name or as a context object.	742	A context can be specified either as package name or as a context object.
668		743
669	=item $ctx->parents ($ctx2[, $ctx3...])	744	=item $ctx->slaves ($ctx2[, $ctx3...])
670		745
671	Replaces all parents attached to this context by the ones given.	746	Replaces all slaves attached to this context by the ones given.
672		747
673	=cut	748	=cut
674		749
675	sub attach {	750	sub attach {
676	my $ctx = shift;	751	my $ctx = shift;
…		…
684		759
685	delete $ctx->[2]{$_+0}	760	delete $ctx->[2]{$_+0}
686	for map { AnyEvent::Log::ctx $_ } @_;	761	for map { AnyEvent::Log::ctx $_ } @_;
687	}	762	}
688		763
689	sub parents {	764	sub slaves {
690	undef $_[0][2];	765	undef $_[0][2];
691	&attach;	766	&attach;
692	}	767	}
693		768
694	=back	769	=back
695		770
696	=head3 MESSAGE LOGGING	771	=head3 LOG TARGETS
697		772
698	The following methods configure how the logging context actually does	773	The following methods configure how the logging context actually does
699	the logging (which consists of formatting the message and printing it or	774	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	775	whatever it wants to do with it).
701	directly to a context, without going via your package context.
702		776
703	=over 4	777	=over 4
704		778
705	=item $ctx->log_cb ($cb->($str))	779	=item $ctx->log_cb ($cb->($str)
706		780
707	Replaces the logging callback on the context (C<undef> disables the	781	Replaces the logging callback on the context (C<undef> disables the
708	logging callback).	782	logging callback).
709		783
710	The logging callback is responsible for handling formatted log messages	784	The logging callback is responsible for handling formatted log messages
711	(see C<fmt_cb> below) - normally simple text strings that end with a	785	(see C<fmt_cb> below) - normally simple text strings that end with a
712	newline (and are possibly multiline themselves).	786	newline (and are possibly multiline themselves).
713		787
714	It also has to return true iff it has consumed the log message, and false	788	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	789	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.	790	slave context. When in doubt, return C<0> from your logging callback.
717		791
718	Example: a very simple logging callback, simply dump the message to STDOUT	792	Example: a very simple logging callback, simply dump the message to STDOUT
719	and do not consume it.	793	and do not consume it.
720		794
721	$ctx->log_cb (sub { print STDERR shift; 0 });	795	$ctx->log_cb (sub { print STDERR shift; 0 });
…		…
729	your program.	803	your program.
730		804
731	$ctx->levels ("debug", "trace");	805	$ctx->levels ("debug", "trace");
732	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages	806	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages
733		807
734	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	808	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $orig_ctx, $level, $message))
735		809
736	Replaces the formatting callback on the context (C<undef> restores the	810	Replaces the formatting callback on the context (C<undef> restores the
737	default formatter).	811	default formatter).
738		812
739	The callback is passed the (possibly fractional) timestamp, the original	813	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	814	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	815	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.	816	string, but it could just as well be an array reference that just stores
		817	the values.
		818
		819	If, for some reason, you want to use C<caller> to find out more baout the
		820	logger then you should walk up the call stack until you are no longer
		821	inside the C<AnyEvent::Log> package.
743		822
744	Example: format just the raw message, with numeric log level in angle	823	Example: format just the raw message, with numeric log level in angle
745	brackets.	824	brackets.
746		825
747	$ctx->fmt_cb (sub {	826	$ctx->fmt_cb (sub {
…		…
764	"$msg->[3]";	843	"$msg->[3]";
765		844
766	0	845	0
767	});	846	});
768		847
		848	=item $ctx->log_to_warn
		849
		850	Sets the C<log_cb> to simply use C<CORE::warn> to report any messages
		851	(usually this logs to STDERR).
		852
		853	=item $ctx->log_to_file ($path)
		854
		855	Sets the C<log_cb> to log to a file (by appending), unbuffered.
		856
		857	=item $ctx->log_to_path ($path)
		858
		859	Same as C<< ->log_to_file >>, but opens the file for each message. This
		860	is much slower, but allows you to change/move/rename/delete the file at
		861	basically any time.
		862
		863	Needless(?) to say, if you do not want to be bitten by some evil person
		864	calling C<chdir>, the path should be absolute. Doesn't help with
		865	C<chroot>, but hey...
		866
		867	=item $ctx->log_to_syslog ([$log_flags])
		868
		869	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and all
		870	the others in the obvious way. If specified, then the C<$log_flags> are
		871	simply or'ed onto the priority argument and can contain any C<LOG_xxx>
		872	flags valid for Sys::Syslog::syslog, except for the priority levels.
		873
		874	Note that this function also sets a C<fmt_cb> - the logging part requires
		875	an array reference with [$level, $str] as input.
		876
769	=cut	877	=cut
770		878
771	sub log_cb {	879	sub log_cb {
772	my ($ctx, $cb) = @_;	880	my ($ctx, $cb) = @_;
773		881
…		…
778	my ($ctx, $cb) = @_;	886	my ($ctx, $cb) = @_;
779		887
780	$ctx->[4] = $cb;	888	$ctx->[4] = $cb;
781	}	889	}
782		890
783	=item $ctx->log ($level, $msg[, @params])	891	sub log_to_warn {
		892	my ($ctx, $path) = @_;
784		893
785	Same as C<AnyEvent::Log::log>, but uses the given context as log context.	894	$ctx->log_cb (sub {
		895	warn shift;
		896	0
		897	});
		898	}
786		899
787	=item $logger = $ctx->logger ($level[, \$enabled])	900	sub log_to_file {
788		901	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		902
820	open my $fh, ">>", $path	903	open my $fh, ">>", $path
821	or die "$path: $!";	904	or die "$path: $!";
822		905
823	$AnyEvent::Log::Default->log_cb (sub {	906	$ctx->log_cb (sub {
824	syswrite $fh, shift;	907	syswrite $fh, shift;
825	0	908	0
826	});	909	});
		910	}
		911
		912	sub log_to_path {
		913	my ($ctx, $path) = @_;
		914
		915	$ctx->log_cb (sub {
		916	open my $fh, ">>", $path
		917	or die "$path: $!";
		918
		919	syswrite $fh, shift;
		920	0
		921	});
		922	}
		923
		924	sub log_to_syslog {
		925	my ($ctx, $flags) = @_;
		926
		927	require Sys::Syslog;
		928
		929	$ctx->fmt_cb (sub {
		930	my $str = $_[3];
		931	$str =~ s/\n(?=.)/\n+ /g;
		932
		933	[$_[2], "($_[1][0]) $str"]
		934	});
		935
		936	$ctx->log_cb (sub {
		937	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;
		938
		939	Sys::Syslog::syslog ($flags \| ($lvl - 1), $_)
		940	for split /\n/, $_[0][1];
		941
		942	0
		943	});
		944	}
		945
		946	=back
		947
		948	=head3 MESSAGE LOGGING
		949
		950	These methods allow you to log messages directly to a context, without
		951	going via your package context.
		952
		953	=over 4
		954
		955	=item $ctx->log ($level, $msg[, @params])
		956
		957	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
		958
		959	=item $logger = $ctx->logger ($level[, \$enabled])
		960
		961	Same as C<AnyEvent::Log::logger>, but uses the given context as log
		962	context.
		963
		964	=cut
		965
		966	*log = \&AnyEvent::Log::_log;
		967	*logger = \&AnyEvent::Log::_logger;
		968
		969	=back
		970
		971	=cut
		972
		973	package AnyEvent::Log;
		974
		975	=head1 CONFIGURATION VIA $ENV{PERL_ANYEVENT_LOG}
		976
		977	Logging can also be configured by setting the environment variable
		978	C<PERL_ANYEVENT_LOG> (or C<AE_LOG>).
		979
		980	The value consists of one or more logging context specifications separated
		981	by C<:> or whitespace. Each logging specification in turn starts with a
		982	context name, followed by C<=>, followed by zero or more comma-separated
		983	configuration directives, here are some examples:
		984
		985	# set default logging level
		986	filter=warn
		987
		988	# log to file instead of to stderr
		989	log=file=/tmp/mylog
		990
		991	# log to file in addition to stderr
		992	log=+%file:%file=file=/tmp/mylog
		993
		994	# enable debug log messages, log warnings and above to syslog
		995	filter=debug:log=+%warnings:%warnings=warn,syslog=LOG_LOCAL0
		996
		997	# log trace messages (only) from AnyEvent::Debug to file
		998	AnyEvent::Debug=+%trace:%trace=only,trace,file=/tmp/tracelog
		999
		1000	A context name in the log specification can be any of the following:
		1001
		1002	=over 4
		1003
		1004	=item C<collect>, C<filter>, C<log>
		1005
		1006	Correspond to the three predefined C<$AnyEvent::Log::COLLECT>,
		1007	C<AnyEvent::Log::FILTER> and C<$AnyEvent::Log::LOG> contexts.
		1008
		1009	=item C<%name>
		1010
		1011	Context names starting with a C<%> are anonymous contexts created when the
		1012	name is first mentioned. The difference to package contexts is that by
		1013	default they have no attached slaves.
		1014
		1015	=item a perl package name
		1016
		1017	Any other string references the logging context associated with the given
		1018	Perl C<package>. In the unlikely case where you want to specify a package
		1019	context that matches on of the other context name forms, you can add a
		1020	C<::> to the package name to force interpretation as a package.
		1021
		1022	=back
		1023
		1024	The configuration specifications can be any number of the following:
		1025
		1026	=over 4
		1027
		1028	=item C<stderr>
		1029
		1030	Configures the context to use Perl's C<warn> function (which typically
		1031	logs to C<STDERR>). Works like C<log_to_warn>.
		1032
		1033	=item C<file=>I<path>
		1034
		1035	Configures the context to log to a file with the given path. Works like
		1036	C<log_to_file>.
		1037
		1038	=item C<path=>I<path>
		1039
		1040	Configures the context to log to a file with the given path. Works like
		1041	C<log_to_path>.
		1042
		1043	=item C<syslog> or C<syslog=>I<expr>
		1044
		1045	Configures the context to log to syslog. If I<expr> is given, then it is
		1046	evaluated in the L<Sys::Syslog> package, so you could use:
		1047
		1048	log=syslog=LOG_LOCAL0
		1049
		1050	=item C<nolog>
		1051
		1052	Configures the context to not log anything by itself, which is the
		1053	default. Same as C<< $ctx->log_cb (undef) >>.
		1054
		1055	=item C<0> or C<off>
		1056
		1057	Sets the logging level of the context ot C<0>, i.e. all messages will be
		1058	filtered out.
		1059
		1060	=item C<all>
		1061
		1062	Enables all logging levels, i.e. filtering will effectively be switched
		1063	off (the default).
		1064
		1065	=item C<only>
		1066
		1067	Disables all logging levels, and changes the interpretation of following
		1068	level specifications to enable the specified level only.
		1069
		1070	Example: only enable debug messages for a context.
		1071
		1072	context=only,debug
		1073
		1074	=item C<except>
		1075
		1076	Enables all logging levels, and changes the interpretation of following
		1077	level specifications to disable that level. Rarely used.
		1078
		1079	Example: enable all logging levels except fatal and trace (this is rather
		1080	nonsensical).
		1081
		1082	filter=exept,fatal,trace
		1083
		1084	=item C<level>
		1085
		1086	Enables all logging levels, and changes the interpretation of following
		1087	level specifications to be "that level or any higher priority
		1088	message". This is the default.
		1089
		1090	Example: log anything at or above warn level.
		1091
		1092	filter=warn
		1093
		1094	# or, more verbose
		1095	filter=only,level,warn
		1096
		1097	=item C<1>..C<9> or a logging level name (C<error>, C<debug> etc.)
		1098
		1099	A numeric loglevel or the name of a loglevel will be interpreted according
		1100	to the most recent C<only>, C<except> or C<level> directive. By default,
		1101	specifying a logging level enables that and any higher priority messages.
		1102
		1103	=item C<+>I<context>
		1104
		1105	Attaches the named context as slave to the context.
		1106
		1107	=item C<+>
		1108
		1109	A line C<+> detaches all contexts, i.e. clears the slave list from the
		1110	context. Anonymous (C<%name>) contexts have no attached slaves by default,
		1111	but package contexts have the parent context as slave by default.
		1112
		1113	Example: log messages from My::Module to a file, do not send them to the
		1114	default log collector.
		1115
		1116	My::Module=+,file=/tmp/mymodulelog
		1117
		1118	=back
		1119
		1120	Any character can be escaped by prefixing it with a C<\> (backslash), as
		1121	usual, so to log to a file containing a comma, colon, backslash and some
		1122	spaces in the filename, you would do this:
		1123
		1124	PERL_ANYEVENT_LOG='log=file=/some\ \:file\ with\,\ \\-escapes'
		1125
		1126	Since whitespace (which includes newlines) is allowed, it is fine to
		1127	specify multiple lines in C<PERL_ANYEVENT_LOG>, e.g.:
		1128
		1129	PERL_ANYEVENT_LOG="
		1130	filter=warn
		1131	AnyEvent::Debug=+%trace
		1132	%trace=only,trace,+log
		1133	" myprog
		1134
		1135	Also, in the unlikely case when you want to concatenate specifications,
		1136	use whitespace as separator, as C<::> will be interpreted as part of a
		1137	module name, an empty spec with two separators:
		1138
		1139	PERL_ANYEVENT_LOG="$PERL_ANYEVENT_LOG MyMod=debug"
		1140
		1141	=cut
		1142
		1143	for (my $spec = $ENV{PERL_ANYEVENT_LOG}) {
		1144	my %anon;
		1145
		1146	my $pkg = sub {
		1147	$_[0] eq "log" ? $LOG
		1148	: $_[0] eq "filter" ? $FILTER
		1149	: $_[0] eq "collect" ? $COLLECT
		1150	: $_[0] =~ /^%(.+)$/ ? ($anon{$1} \|\|= ctx undef)
		1151	: $_[0] =~ /^(.*?)(?:::)?$/ ? ctx "$1" # egad :/
		1152	: die # never reached?
		1153	};
		1154
		1155	/\G[[:space:]]+/gc; # skip initial whitespace
		1156
		1157	while (/\G((?:[^:=[:space:]]+\|::\|\\.)+)=/gc) {
		1158	my $ctx = $pkg->($1);
		1159	my $level = "level";
		1160
		1161	while (/\G((?:[^,:[:space:]]+\|::\|\\.)+)/gc) {
		1162	for ("$1") {
		1163	if ($_ eq "stderr" ) { $ctx->log_to_warn;
		1164	} elsif (/^file=(.+)/ ) { $ctx->log_to_file ("$1");
		1165	} elsif (/^path=(.+)/ ) { $ctx->log_to_path ("$1");
		1166	} elsif (/syslog(?:=(.*))?/ ) { require Sys::Syslog; $ctx->log_to_syslog (eval "package Sys::Syslog; $1");
		1167	} elsif ($_ eq "nolog" ) { $ctx->log_cb (undef);
		1168	} elsif (/^\+(.+)$/ ) { $ctx->attach ($pkg->("$1"));
		1169	} elsif ($_ eq "+" ) { $ctx->slaves;
		1170	} elsif ($_ eq "off" or $_ eq "0") { $ctx->level (0);
		1171	} elsif ($_ eq "all" ) { $ctx->level ("all");
		1172	} elsif ($_ eq "level" ) { $ctx->level ("all"); $level = "level";
		1173	} elsif ($_ eq "only" ) { $ctx->level ("off"); $level = "enable";
		1174	} elsif ($_ eq "except" ) { $ctx->level ("all"); $level = "disable";
		1175	} elsif (/^\d$/ ) { $ctx->$level ($_);
		1176	} elsif (exists $STR2LEVEL{$_} ) { $ctx->$level ($_);
		1177	} else { die "PERL_ANYEVENT_LOG ($spec): parse error at '$_'\n";
		1178	}
		1179	}
		1180
		1181	/\G,/gc or last;
		1182	}
		1183
		1184	/\G[:[:space:]]+/gc or last;
		1185	}
		1186
		1187	/\G[[:space:]]+/gc; # skip trailing whitespace
		1188
		1189	if (/\G(.+)/g) {
		1190	die "PERL_ANYEVENT_LOG ($spec): parse error at '$1'\n";
		1191	}
		1192	}
		1193
		1194	1;
		1195
		1196	=head1 EXAMPLES
		1197
		1198	This section shows some common configurations, both as code, and as
		1199	C<PERL_ANYEVENT_LOG> string.
		1200
		1201	=over 4
		1202
		1203	=item Setting the global logging level.
		1204
		1205	Either put C<PERL_ANYEVENT_VERBOSE=><number> into your environment before
		1206	running your program, use C<PERL_ANYEVENT_LOG> or modify the log level of
		1207	the root context at runtime:
		1208
		1209	PERL_ANYEVENT_VERBOSE=5 ./myprog
		1210
		1211	PERL_ANYEVENT_LOG=log=warn
		1212
		1213	$AnyEvent::Log::FILTER->level ("warn");
		1214
		1215	=item Append all messages to a file instead of sending them to STDERR.
		1216
		1217	This is affected by the global logging level.
		1218
		1219	$AnyEvent::Log::LOG->log_to_file ($path);
		1220
		1221	PERL_ANYEVENT_LOG=log=file=/some/path
827		1222
828	=item Write all messages with priority C<error> and higher to a file.	1223	=item Write all messages with priority C<error> and higher to a file.
829		1224
830	This writes them only when the global logging level allows it, because	1225	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	1226	it is attached to the default context which is invoked I<after> global
832	filtering.	1227	filtering.
833		1228
834	open my $fh, ">>", $path	1229	$AnyEvent::Log::FILTER->attach
835	or die "$path: $!";	1230	new AnyEvent::Log::Ctx log_to_file => $path);
836		1231
837	$AnyEvent::Log::Default->attach (new AnyEvent::Log::Ctx	1232	PERL_ANYEVENT_LOG=filter=+%filelogger:%filelogger=file=/some/path
838	log_cb => sub { syswrite $fh, shift; 0 });
839		1233
840	This writes them regardless of the global logging level, because it is	1234	This writes them regardless of the global logging level, because it is
841	attached to the toplevel context, which receives all messages I<before>	1235	attached to the toplevel context, which receives all messages I<before>
842	the global filtering.	1236	the global filtering.
843		1237
844	$AnyEvent::Log::Top->attach (new AnyEvent::Log::Ctx	1238	$AnyEvent::Log::COLLECT->attach (
845	log_cb => sub { syswrite $fh, shift; 0 });	1239	new AnyEvent::Log::Ctx log_to_file => $path);
846		1240
		1241	PERL_ANYEVENT_LOG=%filelogger=file=/some/path:collect=+%filelogger
		1242
847	In both cases, messages are still written to STDOUT.	1243	In both cases, messages are still written to STDERR.
848		1244
849	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).	1245	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
850		1246
851	Attach the CyAnyEvent::Log::Default> context to the C<AnyEvent::Debug>	1247	Attach the C<$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.	1248	context - this simply circumvents the global filtering for trace messages.
854		1249
855	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;	1250	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
856	$debug->attach ($AnyEvent::Log::Default);	1251	$debug->attach ($AnyEvent::Log::LOG);
857	$debug->levels ("trace"); # not "level"!	1252
		1253	PERL_ANYEVENT_LOG=AnyEvent::Debug=+log
		1254
		1255	This of course works for any package, not just L<AnyEvent::Debug>, but
		1256	assumes the log level for AnyEvent::Debug hasn't been changed from the
		1257	default.
858		1258
859	=back	1259	=back
860		1260
861	=head1 AUTHOR	1261	=head1 AUTHOR
862		1262
863	Marc Lehmann <schmorp@schmorp.de>	1263	Marc Lehmann <schmorp@schmorp.de>
864	http://home.schmorp.de/	1264	http://home.schmorp.de/
865		1265
866	=cut	1266	=cut
		1267

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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 1.38 by root, Fri Aug 26 00:32:45 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 1.38 by root, Fri Aug 26 00:32:45 2011 UTC