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

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.25 by root, Sun Aug 21 03:25:47 2011 UTC vs.
Revision 1.60 by root, Tue Jul 30 23:53:43 2013 UTC

…		…
6		6
7	Simple uses:	7	Simple uses:
8		8
9	use AnyEvent;	9	use AnyEvent;
10		10
11	AE::log debug => "hit my knee";	11	AE::log fatal => "No config found, cannot continue!"; # never returns
12	AE::log warn => "it's a bit too hot";	12	AE::log alert => "The battery died!";
13	AE::log error => "the flag was false!";	13	AE::log crit => "The battery temperature is too hot!";
14	AE::log fatal => "the bit toggled! run!"; # never returns	14	AE::log error => "Division by zero attempted.";
		15	AE::log warn => "Couldn't delete the file.";
		16	AE::log note => "Wanted to create config, but config already exists.";
		17	AE::log info => "File soandso successfully deleted.";
		18	AE::log debug => "the function returned 3";
		19	AE::log trace => "going to call function abc";
15		20
		21	Log level overview:
		22
		23	LVL NAME SYSLOG PERL NOTE
		24	1 fatal emerg exit system unusable, aborts program!
		25	2 alert failure in primary system
		26	3 critical crit failure in backup system
		27	4 error err die non-urgent program errors, a bug
		28	5 warn warning possible problem, not necessarily error
		29	6 note notice unusual conditions
		30	7 info normal messages, no action required
		31	8 debug debugging messages for development
		32	9 trace copious tracing output
		33
16	"Complex" uses (for speed sensitive code):	34	"Complex" uses (for speed sensitive code, e.g. trace/debug messages):
17		35
18	use AnyEvent::Log;	36	use AnyEvent::Log;
19		37
20	my $tracer = AnyEvent::Log::logger trace => \$my $trace;	38	my $tracer = AnyEvent::Log::logger trace => \$my $trace;
21		39
…		…
32		50
33	# send all critical and higher priority messages to syslog,	51	# send all critical and higher priority messages to syslog,
34	# regardless of (most) other settings	52	# regardless of (most) other settings
35	$AnyEvent::Log::COLLECT->attach (new AnyEvent::Log::Ctx	53	$AnyEvent::Log::COLLECT->attach (new AnyEvent::Log::Ctx
36	level => "critical",	54	level => "critical",
37	log_to_syslog => 0,	55	log_to_syslog => "user",
38	);	56	);
39		57
40	=head1 DESCRIPTION	58	=head1 DESCRIPTION
41		59
42	This module implements a relatively simple "logging framework". It doesn't	60	This module implements a relatively simple "logging framework". It doesn't
43	attempt to be "the" logging solution or even "a" logging solution for	61	attempt to be "the" logging solution or even "a" logging solution for
44	AnyEvent - AnyEvent simply creates logging messages internally, and this	62	AnyEvent - AnyEvent simply creates logging messages internally, and this
45	module more or less exposes the mechanism, with some extra spiff to allow	63	module more or less exposes the mechanism, with some extra spiff to allow
46	using it from other modules as well.	64	using it from other modules as well.
47		65
48	Remember that the default verbosity level is C<0> (C<off>), so nothing	66	Remember that the default verbosity level is C<4> (C<error>), so only
49	will be logged, unless you set C<PERL_ANYEVENT_VERBOSE> to a higher number	67	errors and more important messages will be logged, unless you set
50	before starting your program, or change the logging level at runtime with	68	C<PERL_ANYEVENT_VERBOSE> to a higher number before starting your program
51	something like:	69	(C<AE_VERBOSE=5> is recommended during development), or change the logging
		70	level at runtime with something like:
52		71
53	use AnyEvent::Log;	72	use AnyEvent::Log;
54	AnyEvent::Log::FILTER->level ("info");	73	$AnyEvent::Log::FILTER->level ("info");
55		74
56	The design goal behind this module was to keep it simple (and small),	75	The design goal behind this module was to keep it simple (and small),
57	but make it powerful enough to be potentially useful for any module, and	76	but make it powerful enough to be potentially useful for any module, and
58	extensive enough for the most common tasks, such as logging to multiple	77	extensive enough for the most common tasks, such as logging to multiple
59	targets, or being able to log into a database.	78	targets, or being able to log into a database.
60		79
		80	The module is also usable before AnyEvent itself is initialised, in which
		81	case some of the functionality might be reduced.
		82
61	The amount of documentation might indicate otherwise, but the module is	83	The amount of documentation might indicate otherwise, but the runtime part
62	still just below 300 lines of code.	84	of the module is still just below 300 lines of code.
63		85
64	=head1 LOGGING LEVELS	86	=head1 LOGGING LEVELS
65		87
66	Logging levels in this module range from C<1> (highest priority) to C<9>	88	Logging levels in this module range from C<1> (highest priority) to C<9>
67	(lowest priority). Note that the lowest numerical value is the highest	89	(lowest priority). Note that the lowest numerical value is the highest
…		…
69	numerical value".	91	numerical value".
70		92
71	Instead of specifying levels by name you can also specify them by aliases:	93	Instead of specifying levels by name you can also specify them by aliases:
72		94
73	LVL NAME SYSLOG PERL NOTE	95	LVL NAME SYSLOG PERL NOTE
74	1 fatal emerg exit aborts program!	96	1 fatal emerg exit system unusable, aborts program!
75	2 alert	97	2 alert failure in primary system
76	3 critical crit	98	3 critical crit failure in backup system
77	4 error err die	99	4 error err die non-urgent program errors, a bug
78	5 warn warning	100	5 warn warning possible problem, not necessarily error
79	6 note notice	101	6 note notice unusual conditions
80	7 info	102	7 info normal messages, no action required
81	8 debug	103	8 debug debugging messages for development
82	9 trace	104	9 trace copious tracing output
83		105
84	As you can see, some logging levels have multiple aliases - the first one	106	As you can see, some logging levels have multiple aliases - the first one
85	is the "official" name, the second one the "syslog" name (if it differs)	107	is the "official" name, the second one the "syslog" name (if it differs)
86	and the third one the "perl" name, suggesting that you log C<die> messages	108	and the third one the "perl" name, suggesting (only!) that you log C<die>
87	at C<error> priority.	109	messages at C<error> priority. The NOTE column tries to provide some
		110	rationale on how to chose a logging level.
88		111
		112	As a rough guideline, levels 1..3 are primarily meant for users of the
		113	program (admins, staff), and are the only ones logged to STDERR by
		114	default. Levels 4..6 are meant for users and developers alike, while
		115	levels 7..9 are usually meant for developers.
		116
89	You can normally only log a single message at highest priority level	117	You can normally only log a message once at highest priority level (C<1>,
90	(C<1>, C<fatal>), because logging a fatal message will also quit the	118	C<fatal>), because logging a fatal message will also quit the program - so
91	program - so use it sparingly :)	119	use it sparingly :)
		120
		121	For example, a program that finds an unknown switch on the commandline
		122	might well use a fatal logging level to tell users about it - the "system"
		123	in this case would be the program, or module.
92		124
93	Some methods also offer some extra levels, such as C<0>, C<off>, C<none>	125	Some methods also offer some extra levels, such as C<0>, C<off>, C<none>
94	or C<all> - these are only valid in the methods they are documented for.	126	or C<all> - these are only valid for the methods that documented them.
95		127
96	=head1 LOGGING FUNCTIONS	128	=head1 LOGGING FUNCTIONS
97		129
98	These functions allow you to log messages. They always use the caller's	130	The following functions allow you to log messages. They always use the
99	package as a "logging context". Also, the main logging function C<log> is	131	caller's package as a "logging context". Also, the main logging function,
100	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is	132	C<log>, is aliased to C<AnyEvent::log> and C<AE::log> when the C<AnyEvent>
101	loaded.	133	module is loaded.
102		134
103	=over 4	135	=over 4
104		136
105	=cut	137	=cut
106		138
107	package AnyEvent::Log;	139	package AnyEvent::Log;
108		140
109	use Carp ();	141	use Carp ();
110	use POSIX ();	142	use POSIX ();
111		143
		144	# layout of a context
		145	# 0 1 2 3 4, 5
		146	# [$title, $level, %$slaves, &$logcb, &$fmtcb, $cap]
		147
112	use AnyEvent (); BEGIN { AnyEvent::common_sense }	148	use AnyEvent (); BEGIN { AnyEvent::common_sense }
113	use AnyEvent::Util ();	149	#use AnyEvent::Util (); need to load this in a delayed fashion, as it uses AE::log
114		150
115	our $VERSION = $AnyEvent::VERSION;	151	our $VERSION = $AnyEvent::VERSION;
116		152
117	our ($COLLECT, $FILTER, $LOG);	153	our ($COLLECT, $FILTER, $LOG);
118		154
119	our ($now_int, $now_str1, $now_str2);	155	our ($now_int, $now_str1, $now_str2);
120		156
121	# Format Time, not public - yet?	157	# Format Time, not public - yet?
122	sub ft($) {	158	sub format_time($) {
123	my $i = int $_[0];	159	my $i = int $_[0];
124	my $f = sprintf "%06d", 1e6 * ($_[0] - $i);	160	my $f = sprintf "%06d", 1e6 * ($_[0] - $i);
125		161
126	($now_int, $now_str1, $now_str2) = ($i, split /\x01/, POSIX::strftime "%Y-%m-%d %H:%M:%S.\x01 %z", localtime $i)	162	($now_int, $now_str1, $now_str2) = ($i, split /\x01/, POSIX::strftime "%Y-%m-%d %H:%M:%S.\x01 %z", localtime $i)
127	if $now_int != $i;	163	if $now_int != $i;
…		…
148	=item AnyEvent::Log::log $level, $msg[, @args]	184	=item AnyEvent::Log::log $level, $msg[, @args]
149		185
150	Requests logging of the given C<$msg> with the given log level, and	186	Requests logging of the given C<$msg> with the given log level, and
151	returns true if the message was logged I<somewhere>.	187	returns true if the message was logged I<somewhere>.
152		188
153	For C<fatal> log levels, the program will abort.	189	For loglevel C<fatal>, the program will abort.
154		190
155	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the	191	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the
156	C<$msg> is interpreted as an sprintf format string.	192	C<$msg> is interpreted as an sprintf format string.
157		193
158	The C<$msg> should not end with C<\n>, but may if that is convenient for	194	The C<$msg> should not end with C<\n>, but may if that is convenient for
…		…
160		196
161	Last not least, C<$msg> might be a code reference, in which case it is	197	Last not least, C<$msg> might be a code reference, in which case it is
162	supposed to return the message. It will be called only then the message	198	supposed to return the message. It will be called only then the message
163	actually gets logged, which is useful if it is costly to create the	199	actually gets logged, which is useful if it is costly to create the
164	message in the first place.	200	message in the first place.
		201
		202	This function takes care of saving and restoring C<$!> and C<$@>, so you
		203	don't have to.
165		204
166	Whether the given message will be logged depends on the maximum log level	205	Whether the given message will be logged depends on the maximum log level
167	and the caller's package. The return value can be used to ensure that	206	and the caller's package. The return value can be used to ensure that
168	messages or not "lost" - for example, when L<AnyEvent::Debug> detects a	207	messages or not "lost" - for example, when L<AnyEvent::Debug> detects a
169	runtime error it tries to log it at C<die> level, but if that message is	208	runtime error it tries to log it at C<die> level, but if that message is
…		…
203	info => 7,	242	info => 7,
204	debug => 8,	243	debug => 8,
205	trace => 9,	244	trace => 9,
206	);	245	);
207		246
208	sub now () { time }	247	our $TIME_EXACT;
		248
		249	sub exact_time($) {
		250	$TIME_EXACT = shift;
		251	*_ts = $AnyEvent::MODEL
		252	? $TIME_EXACT ? \&AE::now : \&AE::time
		253	: sub () { $TIME_EXACT ? do { require Time::HiRes; Time::HiRes::time () } : time };
		254	}
		255
		256	BEGIN {
		257	exact_time 0;
		258	}
209		259
210	AnyEvent::post_detect {	260	AnyEvent::post_detect {
211	*now = \&AE::now;	261	exact_time $TIME_EXACT;
212	};	262	};
213		263
214	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);	264	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);
215		265
216	# time, ctx, level, msg	266	# time, ctx, level, msg
217	sub _format($$$$) {	267	sub default_format($$$$) {
218	my $ts = ft $_[0];	268	my $ts = format_time $_[0];
219	my $ct = " ";	269	my $ct = " ";
220		270
221	my @res;	271	my @res;
222		272
223	for (split /\n/, sprintf "%-5s %s: %s", $LEVEL2STR[$_[2]], $_[1][0], $_[3]) {	273	for (split /\n/, sprintf "%-5s %s: %s", $LEVEL2STR[$_[2]], $_[1][0], $_[3]) {
…		…
226	}	276	}
227		277
228	join "", @res	278	join "", @res
229	}	279	}
230		280
		281	sub fatal_exit() {
		282	exit 1;
		283	}
		284
231	sub _log {	285	sub _log {
232	my ($ctx, $level, $format, @args) = @_;	286	my ($ctx, $level, $format, @args) = @_;
233		287
234	$level = $level > 0 && $level <= 9	288	$level = $level > 0 && $level <= 9
235	? $level+0	289	? $level+0
236	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";	290	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";
237		291
238	my $mask = 1 << $level;	292	my $mask = 1 << $level;
239		293
240	my ($success, %seen, @ctx, $now, $fmt);	294	my ($success, %seen, @ctx, $now, @fmt);
241		295
242	do	296	do
243	{	297	{
244	# skip if masked	298	# if !ref, then it's a level number
		299	if (!ref $ctx) {
		300	$level = $ctx;
245	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {	301	} elsif ($ctx->[1] & $mask and !$seen{$ctx+0}++) {
		302	# logging/recursing into this context
		303
		304	# level cap
		305	if ($ctx->[5] > $level) {
		306	push @ctx, $level; # restore level when going up in tree
		307	$level = $ctx->[5];
		308	}
		309
		310	# log if log cb
246	if ($ctx->[3]) {	311	if ($ctx->[3]) {
247	# logging target found	312	# logging target found
		313
		314	local ($!, $@);
248		315
249	# now get raw message, unless we have it already	316	# now get raw message, unless we have it already
250	unless ($now) {	317	unless ($now) {
251	$format = $format->() if ref $format;	318	$format = $format->() if ref $format;
252	$format = sprintf $format, @args if @args;	319	$format = sprintf $format, @args if @args;
253	$format =~ s/\n$//;	320	$format =~ s/\n$//;
254	$now = AE::now;	321	$now = _ts;
255	};	322	};
256		323
257	# format msg	324	# format msg
258	my $str = $ctx->[4]	325	my $str = $ctx->[4]
259	? $ctx->[4]($now, $_[0], $level, $format)	326	? $ctx->[4]($now, $_[0], $level, $format)
260	: ($fmt \|\|= _format $now, $_[0], $level, $format);	327	: ($fmt[$level] \|\|= default_format $now, $_[0], $level, $format);
261		328
262	$success = 1;	329	$success = 1;
263		330
264	$ctx->[3]($str)	331	$ctx->[3]($str)
265	or push @ctx, values %{ $ctx->[2] }; # not consumed - propagate	332	or push @ctx, values %{ $ctx->[2] }; # not consumed - propagate
…		…
268	}	335	}
269	}	336	}
270	}	337	}
271	while $ctx = pop @ctx;	338	while $ctx = pop @ctx;
272		339
273	exit 1 if $level <= 1;	340	fatal_exit if $level <= 1;
274		341
275	$success	342	$success
276	}	343	}
277		344
278	sub log($$;@) {	345	sub log($$;@) {
279	_log	346	_log
280	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	347	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
281	@_;	348	@_;
282	}	349	}
283		350
284	AnyEvent::log = AE::log = \&log;
285
286	=item $logger = AnyEvent::Log::logger $level[, \$enabled]	351	=item $logger = AnyEvent::Log::logger $level[, \$enabled]
287		352
288	Creates a code reference that, when called, acts as if the	353	Creates a code reference that, when called, acts as if the
289	C<AnyEvent::Log::log> function was called at this point with the given	354	C<AnyEvent::Log::log> function was called at this point with the given
290	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with	355	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with
…		…
354		419
355	$LOGGER{$logger+0} = $logger;	420	$LOGGER{$logger+0} = $logger;
356		421
357	_reassess $logger+0;	422	_reassess $logger+0;
358		423
		424	require AnyEvent::Util unless $AnyEvent::Util::VERSION;
359	my $guard = AnyEvent::Util::guard {	425	my $guard = AnyEvent::Util::guard (sub {
360	# "clean up"	426	# "clean up"
361	delete $LOGGER{$logger+0};	427	delete $LOGGER{$logger+0};
362	};	428	});
363		429
364	sub {	430	sub {
365	$guard if 0; # keep guard alive, but don't cause runtime overhead	431	$guard if 0; # keep guard alive, but don't cause runtime overhead
366		432
367	_log $ctx, $level, @_	433	_log $ctx, $level, @_
…		…
372	sub logger($;$) {	438	sub logger($;$) {
373	_logger	439	_logger
374	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	440	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
375	@_	441	@_
376	}	442	}
		443
		444	=item AnyEvent::Log::exact_time $on
		445
		446	By default, C<AnyEvent::Log> will use C<AE::now>, i.e. the cached
		447	eventloop time, for the log timestamps. After calling this function with a
		448	true value it will instead resort to C<AE::time>, i.e. fetch the current
		449	time on each log message. This only makes a difference for event loops
		450	that actually cache the time (such as L<EV> or L<AnyEvent::Loop>).
		451
		452	This setting can be changed at any time by calling this function.
		453
		454	Since C<AnyEvent::Log> has to work even before the L<AnyEvent> has been
		455	initialised, this switch will also decide whether to use C<CORE::time> or
		456	C<Time::HiRes::time> when logging a message before L<AnyEvent> becomes
		457	available.
		458
		459	=item AnyEvent::Log::format_time $timestamp
		460
		461	Formats a timestamp as returned by C<< AnyEvent->now > or C<<
		462	AnyEvent->time >> or many other functions in the same way as
		463	C<AnyEvent::Log> does.
		464
		465	In your main program (as opposed to in your module) you can override
		466	the default timestamp display format by loading this module and then
		467	redefining this function.
		468
		469	Most commonly, this function can be used in formatting callbacks.
		470
		471	=item AnyEvent::Log::default_format $time, $ctx, $level, $msg
		472
		473	Format a log message using the given timestamp, logging context, log level
		474	and log message.
		475
		476	This is the formatting function used to format messages when no custom
		477	function is provided.
		478
		479	In your main program (as opposed to in your module) you can override the
		480	default message format by loading this module and then redefining this
		481	function.
		482
		483	=item AnyEvent::Log::fatal_exit
		484
		485	This is the function that is called after logging a C<fatal> log
		486	message. It must not return.
		487
		488	The default implementation simpl calls C<exit 1>.
		489
		490	In your main program (as opposed to in your module) you can override
		491	the fatal exit function by loading this module and then redefining this
		492	function. Make sure you don't return.
377		493
378	=back	494	=back
379		495
380	=head1 LOGGING CONTEXTS	496	=head1 LOGGING CONTEXTS
381		497
…		…
501	This can be used to implement config-file (re-)loading: before loading a	617	This can be used to implement config-file (re-)loading: before loading a
502	configuration, reset all contexts.	618	configuration, reset all contexts.
503		619
504	=cut	620	=cut
505		621
		622	our $ORIG_VERBOSE = $AnyEvent::VERBOSE;
		623	$AnyEvent::VERBOSE = 9;
		624
506	sub reset {	625	sub reset {
507	# hard to kill complex data structures	626	# hard to kill complex data structures
508	# we "recreate" all package loggers and reset the hierarchy	627	# we "recreate" all package loggers and reset the hierarchy
509	while (my ($k, $v) = each %CTX) {	628	while (my ($k, $v) = each %CTX) {
510	@$v = ($k, (1 << 10) - 1 - 1, { });	629	@$v = ($k, (1 << 10) - 1 - 1, { });
…		…
513	}	632	}
514		633
515	@$_ = ($_->[0], (1 << 10) - 1 - 1)	634	@$_ = ($_->[0], (1 << 10) - 1 - 1)
516	for $LOG, $FILTER, $COLLECT;	635	for $LOG, $FILTER, $COLLECT;
517		636
518	$LOG->slaves;	637	#$LOG->slaves;
519	$LOG->title ('$AnyEvent::Log::LOG');	638	$LOG->title ('$AnyEvent::Log::LOG');
520	$LOG->log_cb (sub {	639	$LOG->log_to_warn;
521	warn shift;
522	0
523	});
524		640
525	$FILTER->slaves ($LOG);	641	$FILTER->slaves ($LOG);
526	$FILTER->title ('$AnyEvent::Log::FILTER');	642	$FILTER->title ('$AnyEvent::Log::FILTER');
527	$FILTER->level ($AnyEvent::VERBOSE);	643	$FILTER->level ($ORIG_VERBOSE);
528		644
529	$COLLECT->slaves ($FILTER);	645	$COLLECT->slaves ($FILTER);
530	$COLLECT->title ('$AnyEvent::Log::COLLECT');	646	$COLLECT->title ('$AnyEvent::Log::COLLECT');
531		647
532	_reassess;	648	_reassess;
533	}	649	}
		650
		651	# override AE::log/logger
		652	AnyEvent::log = AE::log = \&log;
		653	AnyEvent::logger = AE::logger = \&logger;
		654
		655	# convert AnyEvent loggers to AnyEvent::Log loggers
		656	$_->[0] = ctx $_->[0] # convert "pkg" to "ctx"
		657	for values %LOGGER;
534		658
535	# create the default logger contexts	659	# create the default logger contexts
536	$LOG = ctx undef;	660	$LOG = ctx undef;
537	$FILTER = ctx undef;	661	$FILTER = ctx undef;
538	$COLLECT = ctx undef;	662	$COLLECT = ctx undef;
…		…
547	package AnyEvent::Log::COLLECT;	671	package AnyEvent::Log::COLLECT;
548	package AE::Log::COLLECT;	672	package AE::Log::COLLECT;
549		673
550	package AnyEvent::Log::Ctx;	674	package AnyEvent::Log::Ctx;
551		675
552	# 0 1 2 3 4
553	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
554
555	=item $ctx = new AnyEvent::Log::Ctx methodname => param...	676	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
556		677
557	This is a convenience constructor that makes it simpler to construct	678	This is a convenience constructor that makes it simpler to construct
558	anonymous logging contexts.	679	anonymous logging contexts.
559		680
…		…
646		767
647	=item $ctx->disable ($level[, $level...])	768	=item $ctx->disable ($level[, $level...])
648		769
649	Disables logging for the given levels, leaving all others unchanged.	770	Disables logging for the given levels, leaving all others unchanged.
650		771
		772	=item $ctx->cap ($level)
		773
		774	Caps the maximum priority to the given level, for all messages logged
		775	to, or passing through, this context. That is, while this doesn't affect
		776	whether a message is logged or passed on, the maximum priority of messages
		777	will be limited to the specified level - messages with a higher priority
		778	will be set to the specified priority.
		779
		780	Another way to view this is that C<< ->level >> filters out messages with
		781	a too low priority, while C<< ->cap >> modifies messages with a too high
		782	priority.
		783
		784	This is useful when different log targets have different interpretations
		785	of priority. For example, for a specific command line program, a wrong
		786	command line switch might well result in a C<fatal> log message, while the
		787	same message, logged to syslog, is likely I<not> fatal to the system or
		788	syslog facility as a whole, but more likely a mere C<error>.
		789
		790	This can be modeled by having a stderr logger that logs messages "as-is"
		791	and a syslog logger that logs messages with a level cap of, say, C<error>,
		792	or, for truly system-critical components, actually C<critical>.
		793
651	=cut	794	=cut
652		795
653	sub _lvl_lst {	796	sub _lvl_lst {
654	map {	797	map {
655	$_ > 0 && $_ <= 9 ? $_+0	798	$_ > 0 && $_ <= 9 ? $_+0
656	: $_ eq "all" ? (1 .. 9)	799	: $_ eq "all" ? (1 .. 9)
657	: $STR2LEVEL{$_} \|\| Carp::croak "$_: not a valid logging level, caught"	800	: $STR2LEVEL{$_} \|\| Carp::croak "$_: not a valid logging level, caught"
658	} @_	801	} @_
659	}	802	}
660		803
		804	sub _lvl {
		805	$_[0] =~ /^(?:0\|off\|none)$/ ? 0 : (_lvl_lst $_[0])[-1]
		806	}
		807
661	our $NOP_CB = sub { 0 };	808	our $NOP_CB = sub { 0 };
662		809
663	sub levels {	810	sub levels {
664	my $ctx = shift;	811	my $ctx = shift;
665	$ctx->[1] = 0;	812	$ctx->[1] = 0;
…		…
668	AnyEvent::Log::_reassess;	815	AnyEvent::Log::_reassess;
669	}	816	}
670		817
671	sub level {	818	sub level {
672	my $ctx = shift;	819	my $ctx = shift;
673	my $lvl = $_[0] =~ /^(?:0\|off\|none)$/ ? 0 : (_lvl_lst $_[0])[-1];
674
675	$ctx->[1] = ((1 << $lvl) - 1) << 1;	820	$ctx->[1] = ((1 << &_lvl) - 1) << 1;
676	AnyEvent::Log::_reassess;	821	AnyEvent::Log::_reassess;
677	}	822	}
678		823
679	sub enable {	824	sub enable {
680	my $ctx = shift;	825	my $ctx = shift;
…		…
688	$ctx->[1] &= ~(1 << $_)	833	$ctx->[1] &= ~(1 << $_)
689	for &_lvl_lst;	834	for &_lvl_lst;
690	AnyEvent::Log::_reassess;	835	AnyEvent::Log::_reassess;
691	}	836	}
692		837
		838	sub cap {
		839	my $ctx = shift;
		840	$ctx->[5] = &_lvl;
		841	}
		842
693	=back	843	=back
694		844
695	=head3 SLAVE CONTEXTS	845	=head3 SLAVE CONTEXTS
696		846
697	The following methods attach and detach another logging context to a	847	The following methods attach and detach another logging context to a
…		…
749	the logging (which consists of formatting the message and printing it or	899	the logging (which consists of formatting the message and printing it or
750	whatever it wants to do with it).	900	whatever it wants to do with it).
751		901
752	=over 4	902	=over 4
753		903
754	=item $ctx->log_cb ($cb->($str)	904	=item $ctx->log_cb ($cb->($str))
755		905
756	Replaces the logging callback on the context (C<undef> disables the	906	Replaces the logging callback on the context (C<undef> disables the
757	logging callback).	907	logging callback).
758		908
759	The logging callback is responsible for handling formatted log messages	909	The logging callback is responsible for handling formatted log messages
…		…
784		934
785	Replaces the formatting callback on the context (C<undef> restores the	935	Replaces the formatting callback on the context (C<undef> restores the
786	default formatter).	936	default formatter).
787		937
788	The callback is passed the (possibly fractional) timestamp, the original	938	The callback is passed the (possibly fractional) timestamp, the original
789	logging context, the (numeric) logging level and the raw message string	939	logging context (object, not title), the (numeric) logging level and
790	and needs to return a formatted log message. In most cases this will be a	940	the raw message string and needs to return a formatted log message. In
791	string, but it could just as well be an array reference that just stores	941	most cases this will be a string, but it could just as well be an array
792	the values.	942	reference that just stores the values.
793		943
794	If, for some reaosn, you want to use C<caller> to find out more baout the	944	If, for some reason, you want to use C<caller> to find out more about the
795	logger then you should walk up the call stack until you are no longer	945	logger then you should walk up the call stack until you are no longer
796	inside the C<AnyEvent::Log> package.	946	inside the C<AnyEvent::Log> package.
797		947
		948	To implement your own logging callback, you might find the
		949	C<AnyEvent::Log::format_time> and C<AnyEvent::Log::default_format>
		950	functions useful.
		951
		952	Example: format the message just as AnyEvent::Log would, by letting
		953	AnyEvent::Log do the work. This is a good basis to design a formatting
		954	callback that only changes minor aspects of the formatting.
		955
		956	$ctx->fmt_cb (sub {
		957	my ($time, $ctx, $lvl, $msg) = @_;
		958
		959	AnyEvent::Log::default_format $time, $ctx, $lvl, $msg
		960	});
		961
798	Example: format just the raw message, with numeric log level in angle	962	Example: format just the raw message, with numeric log level in angle
799	brackets.	963	brackets.
800		964
801	$ctx->fmt_cb (sub {	965	$ctx->fmt_cb (sub {
802	my ($time, $ctx, $lvl, $msg) = @_;	966	my ($time, $ctx, $lvl, $msg) = @_;
803		967
804	"<$lvl>$msg\n"	968	"<$lvl>$msg\n"
805	});	969	});
806		970
807	Example: return an array reference with just the log values, and use	971	Example: return an array reference with just the log values, and use
808	C<PApp::SQL::sql_exec> to store the emssage in a database.	972	C<PApp::SQL::sql_exec> to store the message in a database.
809		973
810	$ctx->fmt_cb (sub { \@_ });	974	$ctx->fmt_cb (sub { \@_ });
811	$ctx->log_cb (sub {	975	$ctx->log_cb (sub {
812	my ($msg) = @_;	976	my ($msg) = @_;
813		977
…		…
818	"$msg->[3]";	982	"$msg->[3]";
819		983
820	0	984	0
821	});	985	});
822		986
		987	=item $ctx->log_to_warn
		988
		989	Sets the C<log_cb> to simply use C<CORE::warn> to report any messages
		990	(usually this logs to STDERR).
		991
823	=item $ctx->log_to_file ($path)	992	=item $ctx->log_to_file ($path)
824		993
825	Sets the C<log_cb> to log to a file (by appending), unbuffered.	994	Sets the C<log_cb> to log to a file (by appending), unbuffered. The
		995	function might return before the log file has been opened or created.
826		996
827	=item $ctx->log_to_path ($path)	997	=item $ctx->log_to_path ($path)
828		998
829	Same as C<< ->log_to_file >>, but opens the file for each message. This	999	Same as C<< ->log_to_file >>, but opens the file for each message. This
830	is much slower, but allows you to change/move/rename/delete the file at	1000	is much slower, but allows you to change/move/rename/delete the file at
831	basically any time.	1001	basically any time.
832		1002
		1003	Needless(?) to say, if you do not want to be bitten by some evil person
		1004	calling C<chdir>, the path should be absolute. Doesn't help with
		1005	C<chroot>, but hey...
		1006
833	=item $ctx->log_to_syslog ([$log_flags])	1007	=item $ctx->log_to_syslog ([$facility])
834		1008
835	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and all	1009	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and
836	the others in the obvious way. If specified, then the C<$log_flags> are	1010	all the others in the obvious way. If specified, then the C<$facility> is
837	simply or'ed onto the priority argument and can contain any C<LOG_xxx>	1011	used as the facility (C<user>, C<auth>, C<local0> and so on). The default
838	flags valid for Sys::Syslog::syslog, except for the priority levels.	1012	facility is C<user>.
839		1013
840	Note that this function also sets a C<fmt_cb> - the logging part requires	1014	Note that this function also sets a C<fmt_cb> - the logging part requires
841	an array reference with [$level, $str] as input.	1015	an array reference with [$level, $str] as input.
842		1016
843	=cut	1017	=cut
…		…
852	my ($ctx, $cb) = @_;	1026	my ($ctx, $cb) = @_;
853		1027
854	$ctx->[4] = $cb;	1028	$ctx->[4] = $cb;
855	}	1029	}
856		1030
		1031	sub log_to_warn {
		1032	my ($ctx, $path) = @_;
		1033
		1034	$ctx->log_cb (sub {
		1035	warn shift;
		1036	0
		1037	});
		1038	}
		1039
		1040	# this function is a good example of why threads are a must,
		1041	# simply for priority inversion.
		1042	sub _log_to_disk {
		1043	# eval'uating this at runtime saves 220kb rss - perl has become
		1044	# an insane memory waster.
		1045	eval q{ # poor man's autoloading {}
		1046	sub _log_to_disk {
		1047	my ($ctx, $path, $keepopen) = @_;
		1048
		1049	my $fh;
		1050	my @queue;
		1051	my $delay;
		1052	my $disable;
		1053
		1054	use AnyEvent::IO ();
		1055
		1056	my $kick = sub {
		1057	undef $delay;
		1058	return unless @queue;
		1059	$delay = 1;
		1060
		1061	# we pass $kick to $kick, so $kick itself doesn't keep a reference to $kick.
		1062	my $kick = shift;
		1063
		1064	# write one or more messages
		1065	my $write = sub {
		1066	# we write as many messages as have been queued
		1067	my $data = join "", @queue;
		1068	@queue = ();
		1069
		1070	AnyEvent::IO::aio_write $fh, $data, sub {
		1071	$disable = 1;
		1072	@_
		1073	? ($_[0] == length $data or AE::log 4 => "unable to write to logfile '$path': short write")
		1074	: AE::log 4 => "unable to write to logfile '$path': $!";
		1075	undef $disable;
		1076
		1077	if ($keepopen) {
		1078	$kick->($kick);
		1079	} else {
		1080	AnyEvent::IO::aio_close ($fh, sub {
		1081	undef $fh;
		1082	$kick->($kick);
		1083	});
		1084	}
		1085	};
		1086	};
		1087
		1088	if ($fh) {
		1089	$write->();
		1090	} else {
		1091	AnyEvent::IO::aio_open
		1092	$path,
		1093	AnyEvent::IO::O_CREAT \| AnyEvent::IO::O_WRONLY \| AnyEvent::IO::O_APPEND,
		1094	0666,
		1095	sub {
		1096	$fh = shift
		1097	or do {
		1098	$disable = 1;
		1099	AE::log 4 => "unable to open logfile '$path': $!";
		1100	undef $disable;
		1101	return;
		1102	};
		1103
		1104	$write->();
		1105	}
		1106	;
		1107	}
		1108	};
		1109
		1110	$ctx->log_cb (sub {
		1111	return if $disable;
		1112	push @queue, shift;
		1113	$kick->($kick) unless $delay;
		1114	0
		1115	});
		1116
		1117	$kick->($kick) if $keepopen; # initial open
		1118	};
		1119	};
		1120	die if $@;
		1121	&_log_to_disk
		1122	}
		1123
857	sub log_to_file {	1124	sub log_to_file {
858	my ($ctx, $path) = @_;	1125	my ($ctx, $path) = @_;
859		1126
860	open my $fh, ">>", $path	1127	_log_to_disk $ctx, $path, 1;
861	or die "$path: $!";
862
863	$ctx->log_cb (sub {
864	syswrite $fh, shift;
865	0
866	});
867	}	1128	}
868		1129
869	sub log_to_file {	1130	sub log_to_path {
870	my ($ctx, $path) = @_;	1131	my ($ctx, $path) = @_;
871		1132
872	$ctx->log_cb (sub {	1133	_log_to_disk $ctx, $path, 0;
873	open my $fh, ">>", $path
874	or die "$path: $!";
875
876	syswrite $fh, shift;
877	0
878	});
879	}	1134	}
880		1135
881	sub log_to_syslog {	1136	sub log_to_syslog {
882	my ($ctx, $flags) = @_;	1137	my ($ctx, $facility) = @_;
883		1138
884	require Sys::Syslog;	1139	require Sys::Syslog;
885		1140
886	$ctx->fmt_cb (sub {	1141	$ctx->fmt_cb (sub {
887	my $str = $_[3];	1142	my $str = $_[3];
888	$str =~ s/\n(?=.)/\n+ /g;	1143	$str =~ s/\n(?=.)/\n+ /g;
889		1144
890	[$_[2], "($_[1][0]) $str"]	1145	[$_[2], "($_[1][0]) $str"]
891	});	1146	});
892		1147
		1148	$facility \|\|= "user";
		1149
893	$ctx->log_cb (sub {	1150	$ctx->log_cb (sub {
894	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;	1151	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;
895		1152
896	Sys::Syslog::syslog ($flags \| ($lvl - 1), $_)	1153	Sys::Syslog::syslog ("$facility\|" . ($lvl - 1), $_)
897	for split /\n/, $_[0][1];	1154	for split /\n/, $_[0][1];
898		1155
899	0	1156	0
900	});	1157	});
901	}	1158	}
…		…
911		1168
912	=item $ctx->log ($level, $msg[, @params])	1169	=item $ctx->log ($level, $msg[, @params])
913		1170
914	Same as C<AnyEvent::Log::log>, but uses the given context as log context.	1171	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
915		1172
		1173	Example: log a message in the context of another package.
		1174
		1175	(AnyEvent::Log::ctx "Other::Package")->log (warn => "heely bo");
		1176
916	=item $logger = $ctx->logger ($level[, \$enabled])	1177	=item $logger = $ctx->logger ($level[, \$enabled])
917		1178
918	Same as C<AnyEvent::Log::logger>, but uses the given context as log	1179	Same as C<AnyEvent::Log::logger>, but uses the given context as log
919	context.	1180	context.
920		1181
921	=cut	1182	=cut
922		1183
923	*log = \&AnyEvent::Log::_log;	1184	*log = \&AnyEvent::Log::_log;
924	*logger = \&AnyEvent::Log::_logger;	1185	*logger = \&AnyEvent::Log::_logger;
925		1186
926	1;
927
928	=back	1187	=back
929		1188
		1189	=cut
		1190
		1191	package AnyEvent::Log;
		1192
		1193	=head1 CONFIGURATION VIA $ENV{PERL_ANYEVENT_LOG}
		1194
		1195	Logging can also be configured by setting the environment variable
		1196	C<PERL_ANYEVENT_LOG> (or C<AE_LOG>).
		1197
		1198	The value consists of one or more logging context specifications separated
		1199	by C<:> or whitespace. Each logging specification in turn starts with a
		1200	context name, followed by C<=>, followed by zero or more comma-separated
		1201	configuration directives, here are some examples:
		1202
		1203	# set default logging level
		1204	filter=warn
		1205
		1206	# log to file instead of to stderr
		1207	log=file=/tmp/mylog
		1208
		1209	# log to file in addition to stderr
		1210	log=+%file:%file=file=/tmp/mylog
		1211
		1212	# enable debug log messages, log warnings and above to syslog
		1213	filter=debug:log=+%warnings:%warnings=warn,syslog=LOG_LOCAL0
		1214
		1215	# log trace messages (only) from AnyEvent::Debug to file
		1216	AnyEvent::Debug=+%trace:%trace=only,trace,file=/tmp/tracelog
		1217
		1218	A context name in the log specification can be any of the following:
		1219
		1220	=over 4
		1221
		1222	=item C<collect>, C<filter>, C<log>
		1223
		1224	Correspond to the three predefined C<$AnyEvent::Log::COLLECT>,
		1225	C<AnyEvent::Log::FILTER> and C<$AnyEvent::Log::LOG> contexts.
		1226
		1227	=item C<%name>
		1228
		1229	Context names starting with a C<%> are anonymous contexts created when the
		1230	name is first mentioned. The difference to package contexts is that by
		1231	default they have no attached slaves.
		1232
		1233	=item a perl package name
		1234
		1235	Any other string references the logging context associated with the given
		1236	Perl C<package>. In the unlikely case where you want to specify a package
		1237	context that matches on of the other context name forms, you can add a
		1238	C<::> to the package name to force interpretation as a package.
		1239
		1240	=back
		1241
		1242	The configuration specifications can be any number of the following:
		1243
		1244	=over 4
		1245
		1246	=item C<stderr>
		1247
		1248	Configures the context to use Perl's C<warn> function (which typically
		1249	logs to C<STDERR>). Works like C<log_to_warn>.
		1250
		1251	=item C<file=>I<path>
		1252
		1253	Configures the context to log to a file with the given path. Works like
		1254	C<log_to_file>.
		1255
		1256	=item C<path=>I<path>
		1257
		1258	Configures the context to log to a file with the given path. Works like
		1259	C<log_to_path>.
		1260
		1261	=item C<syslog> or C<syslog=>I<expr>
		1262
		1263	Configures the context to log to syslog. If I<expr> is given, then it is
		1264	evaluated in the L<Sys::Syslog> package, so you could use:
		1265
		1266	log=syslog=LOG_LOCAL0
		1267
		1268	=item C<nolog>
		1269
		1270	Configures the context to not log anything by itself, which is the
		1271	default. Same as C<< $ctx->log_cb (undef) >>.
		1272
		1273	=item C<cap=>I<level>
		1274
		1275	Caps logging messages entering this context at the given level, i.e.
		1276	reduces the priority of messages with higher priority than this level. The
		1277	default is C<0> (or C<off>), meaning the priority will not be touched.
		1278
		1279	=item C<0> or C<off>
		1280
		1281	Sets the logging level of the context to C<0>, i.e. all messages will be
		1282	filtered out.
		1283
		1284	=item C<all>
		1285
		1286	Enables all logging levels, i.e. filtering will effectively be switched
		1287	off (the default).
		1288
		1289	=item C<only>
		1290
		1291	Disables all logging levels, and changes the interpretation of following
		1292	level specifications to enable the specified level only.
		1293
		1294	Example: only enable debug messages for a context.
		1295
		1296	context=only,debug
		1297
		1298	=item C<except>
		1299
		1300	Enables all logging levels, and changes the interpretation of following
		1301	level specifications to disable that level. Rarely used.
		1302
		1303	Example: enable all logging levels except fatal and trace (this is rather
		1304	nonsensical).
		1305
		1306	filter=exept,fatal,trace
		1307
		1308	=item C<level>
		1309
		1310	Enables all logging levels, and changes the interpretation of following
		1311	level specifications to be "that level or any higher priority
		1312	message". This is the default.
		1313
		1314	Example: log anything at or above warn level.
		1315
		1316	filter=warn
		1317
		1318	# or, more verbose
		1319	filter=only,level,warn
		1320
		1321	=item C<1>..C<9> or a logging level name (C<error>, C<debug> etc.)
		1322
		1323	A numeric loglevel or the name of a loglevel will be interpreted according
		1324	to the most recent C<only>, C<except> or C<level> directive. By default,
		1325	specifying a logging level enables that and any higher priority messages.
		1326
		1327	=item C<+>I<context>
		1328
		1329	Attaches the named context as slave to the context.
		1330
		1331	=item C<+>
		1332
		1333	A lone C<+> detaches all contexts, i.e. clears the slave list from the
		1334	context. Anonymous (C<%name>) contexts have no attached slaves by default,
		1335	but package contexts have the parent context as slave by default.
		1336
		1337	Example: log messages from My::Module to a file, do not send them to the
		1338	default log collector.
		1339
		1340	My::Module=+,file=/tmp/mymodulelog
		1341
		1342	=back
		1343
		1344	Any character can be escaped by prefixing it with a C<\> (backslash), as
		1345	usual, so to log to a file containing a comma, colon, backslash and some
		1346	spaces in the filename, you would do this:
		1347
		1348	PERL_ANYEVENT_LOG='log=file=/some\ \:file\ with\,\ \\-escapes'
		1349
		1350	Since whitespace (which includes newlines) is allowed, it is fine to
		1351	specify multiple lines in C<PERL_ANYEVENT_LOG>, e.g.:
		1352
		1353	PERL_ANYEVENT_LOG="
		1354	filter=warn
		1355	AnyEvent::Debug=+%trace
		1356	%trace=only,trace,+log
		1357	" myprog
		1358
		1359	Also, in the unlikely case when you want to concatenate specifications,
		1360	use whitespace as separator, as C<::> will be interpreted as part of a
		1361	module name, an empty spec with two separators:
		1362
		1363	PERL_ANYEVENT_LOG="$PERL_ANYEVENT_LOG MyMod=debug"
		1364
		1365	=cut
		1366
		1367	for (my $spec = $ENV{PERL_ANYEVENT_LOG}) {
		1368	my %anon;
		1369
		1370	my $pkg = sub {
		1371	$_[0] eq "log" ? $LOG
		1372	: $_[0] eq "filter" ? $FILTER
		1373	: $_[0] eq "collect" ? $COLLECT
		1374	: $_[0] =~ /^%(.+)$/ ? ($anon{$1} \|\|= do { my $ctx = ctx undef; $ctx->[0] = $_[0]; $ctx })
		1375	: $_[0] =~ /^(.*?)(?:::)?$/ ? ctx "$1" # egad :/
		1376	: die # never reached?
		1377	};
		1378
		1379	/\G[[:space:]]+/gc; # skip initial whitespace
		1380
		1381	while (/\G((?:[^:=[:space:]]+\|::\|\\.)+)=/gc) {
		1382	my $ctx = $pkg->($1);
		1383	my $level = "level";
		1384
		1385	while (/\G((?:[^,:[:space:]]+\|::\|\\.)+)/gc) {
		1386	for ("$1") {
		1387	if ($_ eq "stderr" ) { $ctx->log_to_warn;
		1388	} elsif (/^file=(.+)/ ) { $ctx->log_to_file ("$1");
		1389	} elsif (/^path=(.+)/ ) { $ctx->log_to_path ("$1");
		1390	} elsif (/^syslog(?:=(.*))?/ ) { require Sys::Syslog; $ctx->log_to_syslog ("$1");
		1391	} elsif ($_ eq "nolog" ) { $ctx->log_cb (undef);
		1392	} elsif (/^cap=(.+)/ ) { $ctx->cap ("$1");
		1393	} elsif (/^\+(.+)$/ ) { $ctx->attach ($pkg->("$1"));
		1394	} elsif ($_ eq "+" ) { $ctx->slaves;
		1395	} elsif ($_ eq "off" or $_ eq "0") { $ctx->level (0);
		1396	} elsif ($_ eq "all" ) { $ctx->level ("all");
		1397	} elsif ($_ eq "level" ) { $ctx->level ("all"); $level = "level";
		1398	} elsif ($_ eq "only" ) { $ctx->level ("off"); $level = "enable";
		1399	} elsif ($_ eq "except" ) { $ctx->level ("all"); $level = "disable";
		1400	} elsif (/^\d$/ ) { $ctx->$level ($_);
		1401	} elsif (exists $STR2LEVEL{$_} ) { $ctx->$level ($_);
		1402	} else { die "PERL_ANYEVENT_LOG ($spec): parse error at '$_'\n";
		1403	}
		1404	}
		1405
		1406	/\G,/gc or last;
		1407	}
		1408
		1409	/\G[:[:space:]]+/gc or last;
		1410	}
		1411
		1412	/\G[[:space:]]+/gc; # skip trailing whitespace
		1413
		1414	if (/\G(.+)/g) {
		1415	die "PERL_ANYEVENT_LOG ($spec): parse error at '$1'\n";
		1416	}
		1417	}
		1418
930	=head1 EXAMPLES	1419	=head1 EXAMPLES
931		1420
932	This section shows some common configurations.	1421	This section shows some common configurations, both as code, and as
		1422	C<PERL_ANYEVENT_LOG> string.
933		1423
934	=over 4	1424	=over 4
935		1425
936	=item Setting the global logging level.	1426	=item Setting the global logging level.
937		1427
938	Either put PERL_ANYEVENT_VERBOSE=<number> into your environment before	1428	Either put C<PERL_ANYEVENT_VERBOSE=><number> into your environment before
939	running your program, or modify the log level of the root context:	1429	running your program, use C<PERL_ANYEVENT_LOG> or modify the log level of
		1430	the root context at runtime:
940		1431
941	PERL_ANYEVENT_VERBOSE=5 ./myprog	1432	PERL_ANYEVENT_VERBOSE=5 ./myprog
942		1433
		1434	PERL_ANYEVENT_LOG=log=warn
		1435
943	$AnyEvent::Log::FILTER->level ("warn");	1436	$AnyEvent::Log::FILTER->level ("warn");
944		1437
945	=item Append all messages to a file instead of sending them to STDERR.	1438	=item Append all messages to a file instead of sending them to STDERR.
946		1439
947	This is affected by the global logging level.	1440	This is affected by the global logging level.
948		1441
949	$AnyEvent::Log::LOG->log_to_file ($path); (sub {	1442	$AnyEvent::Log::LOG->log_to_file ($path);
		1443
		1444	PERL_ANYEVENT_LOG=log=file=/some/path
950		1445
951	=item Write all messages with priority C<error> and higher to a file.	1446	=item Write all messages with priority C<error> and higher to a file.
952		1447
953	This writes them only when the global logging level allows it, because	1448	This writes them only when the global logging level allows it, because
954	it is attached to the default context which is invoked I<after> global	1449	it is attached to the default context which is invoked I<after> global
955	filtering.	1450	filtering.
956		1451
957	$AnyEvent::Log::FILTER->attach	1452	$AnyEvent::Log::FILTER->attach (
958	new AnyEvent::Log::Ctx log_to_file => $path);	1453	new AnyEvent::Log::Ctx log_to_file => $path);
		1454
		1455	PERL_ANYEVENT_LOG=filter=+%filelogger:%filelogger=file=/some/path
959		1456
960	This writes them regardless of the global logging level, because it is	1457	This writes them regardless of the global logging level, because it is
961	attached to the toplevel context, which receives all messages I<before>	1458	attached to the toplevel context, which receives all messages I<before>
962	the global filtering.	1459	the global filtering.
963		1460
964	$AnyEvent::Log::COLLECT->attach (	1461	$AnyEvent::Log::COLLECT->attach (
965	new AnyEvent::Log::Ctx log_to_file => $path);	1462	new AnyEvent::Log::Ctx log_to_file => $path);
966		1463
		1464	PERL_ANYEVENT_LOG=%filelogger=file=/some/path:collect=+%filelogger
		1465
967	In both cases, messages are still written to STDERR.	1466	In both cases, messages are still written to STDERR.
		1467
		1468	=item Additionally log all messages with C<warn> and higher priority to
		1469	C<syslog>, but cap at C<error>.
		1470
		1471	This logs all messages to the default log target, but also logs messages
		1472	with priority C<warn> or higher (and not filtered otherwise) to syslog
		1473	facility C<user>. Messages with priority higher than C<error> will be
		1474	logged with level C<error>.
		1475
		1476	$AnyEvent::Log::LOG->attach (
		1477	new AnyEvent::Log::Ctx
		1478	level => "warn",
		1479	cap => "error",
		1480	syslog => "user",
		1481	);
		1482
		1483	PERL_ANYEVENT_LOG=log=+%syslog:%syslog=warn,cap=error,syslog
968		1484
969	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).	1485	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
970		1486
971	Attach the C<$AnyEvent::Log::LOG> context to the C<AnyEvent::Debug>	1487	Attach the C<$AnyEvent::Log::LOG> context to the C<AnyEvent::Debug>
972	context - this simply circumvents the global filtering for trace messages.	1488	context - this simply circumvents the global filtering for trace messages.
973		1489
974	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;	1490	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
975	$debug->attach ($AnyEvent::Log::LOG);	1491	$debug->attach ($AnyEvent::Log::LOG);
		1492
		1493	PERL_ANYEVENT_LOG=AnyEvent::Debug=+log
976		1494
977	This of course works for any package, not just L<AnyEvent::Debug>, but	1495	This of course works for any package, not just L<AnyEvent::Debug>, but
978	assumes the log level for AnyEvent::Debug hasn't been changed from the	1496	assumes the log level for AnyEvent::Debug hasn't been changed from the
979	default.	1497	default.
980		1498
981	=back	1499	=back
982		1500
983	=head1 AUTHOR	1501	=head1 AUTHOR
984		1502
985	Marc Lehmann <schmorp@schmorp.de>	1503	Marc Lehmann <schmorp@schmorp.de>
986	http://home.schmorp.de/	1504	http://anyevent.schmorp.de
987		1505
988	=cut	1506	=cut
		1507
		1508	1
		1509

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents): Revision 1.25 by root, Sun Aug 21 03:25:47 2011 UTC vs. Revision 1.60 by root, Tue Jul 30 23:53:43 2013 UTC

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.25 by root, Sun Aug 21 03:25:47 2011 UTC vs.
Revision 1.60 by root, Tue Jul 30 23:53:43 2013 UTC