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

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.11 by root, Sat Aug 20 01:03:09 2011 UTC vs.
Revision 1.41 by root, Thu Sep 1 04:07:18 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	# available log levels in order:
		17	# fatal alert critical error warn note info debug trace
		18
		19	"Complex" uses (for speed sensitive code):
		20
16	use AnyEvent::Log;	21	use AnyEvent::Log;
17		22
18	my $tracer = AnyEvent::Log::logger trace => \$my $trace;	23	my $tracer = AnyEvent::Log::logger trace => \$my $trace;
19		24
20	$tracer->("i am here") if $trace;	25	$tracer->("i am here") if $trace;
21	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;	26	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;
22		27
23	# configuration	28	Configuration (also look at the EXAMPLES section):
24		29
25	# set logging for this package to maximum	30	# set logging for the current package to errors and higher only
26	AnyEvent::Log::ctx->level ("all");	31	AnyEvent::Log::ctx->level ("error");
27		32
28	# set logging globally to anything below debug	33	# set logging level to suppress anything below "notice"
29	(AnyEvent::Log::ctx "")->level ("notice");	34	$AnyEvent::Log::FILTER->level ("notice");
30		35
31	# see also EXAMPLES, below	36	# send all critical and higher priority messages to syslog,
32		37	# regardless of (most) other settings
33	# disable logging for package "AnyEvent" and all packages below it	38	$AnyEvent::Log::COLLECT->attach (new AnyEvent::Log::Ctx
34	AnyEvent->AnyEvent::Log::ctx->level (0);	39	level => "critical",
35		40	log_to_syslog => "user",
36	# log everything below debug to a file, for the whole program	41	);
37	my $ctx = AnyEvent::Log::ctx;
38	$ctx->log_cb (sub { print FILE shift; 0 });
39	(AnyEvent::Log::ctx "")->add ($ctx);
40		42
41	=head1 DESCRIPTION	43	=head1 DESCRIPTION
42		44
43	This module implements a relatively simple "logging framework". It doesn't	45	This module implements a relatively simple "logging framework". It doesn't
44	attempt to be "the" logging solution or even "a" logging solution for	46	attempt to be "the" logging solution or even "a" logging solution for
45	AnyEvent - AnyEvent simply creates logging messages internally, and this	47	AnyEvent - AnyEvent simply creates logging messages internally, and this
46	module more or less exposes the mechanism, with some extra spiff to allow	48	module more or less exposes the mechanism, with some extra spiff to allow
47	using it from other modules as well.	49	using it from other modules as well.
48		50
49	Remember that the default verbosity level is C<0>, so nothing will be	51	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	52	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	53	before starting your program, or change the logging level at runtime with
52	something like:	54	something like:
53		55
54	use AnyEvent;	56	use AnyEvent::Log;
55	(AnyEvent::Log::ctx "")->level ("info");	57	$AnyEvent::Log::FILTER->level ("info");
56		58
57	The design goal behind this module was to keep it simple (and small),	59	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	60	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	61	extensive enough for the most common tasks, such as logging to multiple
60	targets, or being able to log into a database.	62	targets, or being able to log into a database.
61		63
		64	The module is also usable before AnyEvent itself is initialised, in which
		65	case some of the functionality might be reduced.
		66
		67	The amount of documentation might indicate otherwise, but the runtime part
		68	of the module is still just below 300 lines of code.
		69
		70	=head1 LOGGING LEVELS
		71
		72	Logging levels in this module range from C<1> (highest priority) to C<9>
		73	(lowest priority). Note that the lowest numerical value is the highest
		74	priority, so when this document says "higher priority" it means "lower
		75	numerical value".
		76
		77	Instead of specifying levels by name you can also specify them by aliases:
		78
		79	LVL NAME SYSLOG PERL NOTE
		80	1 fatal emerg exit aborts program!
		81	2 alert
		82	3 critical crit
		83	4 error err die
		84	5 warn warning
		85	6 note notice
		86	7 info
		87	8 debug
		88	9 trace
		89
		90	As you can see, some logging levels have multiple aliases - the first one
		91	is the "official" name, the second one the "syslog" name (if it differs)
		92	and the third one the "perl" name, suggesting (only!) that you log C<die>
		93	messages at C<error> priority.
		94
		95	You can normally only log a single message at highest priority level
		96	(C<1>, C<fatal>), because logging a fatal message will also quit the
		97	program - so use it sparingly :)
		98
		99	Some methods also offer some extra levels, such as C<0>, C<off>, C<none>
		100	or C<all> - these are only valid in the methods they are documented for.
		101
62	=head1 LOGGING FUNCTIONS	102	=head1 LOGGING FUNCTIONS
63		103
64	These functions allow you to log messages. They always use the caller's	104	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	105	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	106	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is
67	loaded.	107	loaded.
68		108
69	=over 4	109	=over 4
70		110
…		…
74		114
75	use Carp ();	115	use Carp ();
76	use POSIX ();	116	use POSIX ();
77		117
78	use AnyEvent (); BEGIN { AnyEvent::common_sense }	118	use AnyEvent (); BEGIN { AnyEvent::common_sense }
79	use AnyEvent::Util ();	119	#use AnyEvent::Util (); need to load this in a delayed fashion, as it uses AE::log
		120
		121	our $VERSION = $AnyEvent::VERSION;
		122
		123	our ($COLLECT, $FILTER, $LOG);
80		124
81	our ($now_int, $now_str1, $now_str2);	125	our ($now_int, $now_str1, $now_str2);
82		126
83	# Format Time, not public - yet?	127	# Format Time, not public - yet?
84	sub ft($) {	128	sub ft($) {
…		…
89	if $now_int != $i;	133	if $now_int != $i;
90		134
91	"$now_str1$f$now_str2"	135	"$now_str1$f$now_str2"
92	}	136	}
93		137
94	our %CTX; # all logging contexts	138	our %CTX; # all package contexts
95		139
96	# creates a default package context object for the given package	140	# creates a default package context object for the given package
97	sub _pkg_ctx($) {	141	sub _pkg_ctx($) {
98	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";	142	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";
99		143
100	# link "parent" package	144	# link "parent" package
101	my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "AE::Log::Top";	145	my $parent = $_[0] =~ /^(.+)::/
		146	? $CTX{$1} \|\|= &_pkg_ctx ("$1")
		147	: $COLLECT;
102		148
103	$pkg = $CTX{$pkg} \|\|= &_pkg_ctx ($pkg);
104	$ctx->[2]{$pkg+0} = $pkg;	149	$ctx->[2]{$parent+0} = $parent;
105		150
106	$ctx	151	$ctx
107	}	152	}
108		153
109	=item AnyEvent::Log::log $level, $msg[, @args]	154	=item AnyEvent::Log::log $level, $msg[, @args]
110		155
111	Requests logging of the given C<$msg> with the given log level (1..9).	156	Requests logging of the given C<$msg> with the given log level, and
112	You can also use the following strings as log level: C<fatal> (1),	157	returns true if the message was logged I<somewhere>.
113	C<alert> (2), C<critical> (3), C<error> (4), C<warn> (5), C<note> (6),
114	C<info> (7), C<debug> (8), C<trace> (9).
115		158
116	For C<fatal> log levels, the program will abort.	159	For loglevel C<fatal>, the program will abort.
117		160
118	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the	161	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.	162	C<$msg> is interpreted as an sprintf format string.
120		163
121	The C<$msg> should not end with C<\n>, but may if that is convenient for	164	The C<$msg> should not end with C<\n>, but may if that is convenient for
…		…
125	supposed to return the message. It will be called only then the message	168	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	169	actually gets logged, which is useful if it is costly to create the
127	message in the first place.	170	message in the first place.
128		171
129	Whether the given message will be logged depends on the maximum log level	172	Whether the given message will be logged depends on the maximum log level
130	and the caller's package.	173	and the caller's package. The return value can be used to ensure that
		174	messages or not "lost" - for example, when L<AnyEvent::Debug> detects a
		175	runtime error it tries to log it at C<die> level, but if that message is
		176	lost it simply uses warn.
131		177
132	Note that you can (and should) call this function as C<AnyEvent::log> or	178	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	179	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	180	need any additional functionality), as those functions will load the
135	logging module on demand only. They are also much shorter to write.	181	logging module on demand only. They are also much shorter to write.
…		…
152		198
153	=cut	199	=cut
154		200
155	# also allow syslog equivalent names	201	# also allow syslog equivalent names
156	our %STR2LEVEL = (	202	our %STR2LEVEL = (
157	fatal => 1, emerg => 1,	203	fatal => 1, emerg => 1, exit => 1,
158	alert => 2,	204	alert => 2,
159	critical => 3, crit => 3,	205	critical => 3, crit => 3,
160	error => 4, err => 4,	206	error => 4, err => 4, die => 4,
161	warn => 5, warning => 5,	207	warn => 5, warning => 5,
162	note => 6, notice => 6,	208	note => 6, notice => 6,
163	info => 7,	209	info => 7,
164	debug => 8,	210	debug => 8,
165	trace => 9,	211	trace => 9,
166	);	212	);
167		213
168	sub now () { time }	214	our $TIME_EXACT;
		215
		216	sub exact_time($) {
		217	$TIME_EXACT = shift;
		218	*_ts = $AnyEvent::MODEL
		219	? $TIME_EXACT ? \&AE::now : \&AE::time
		220	: sub () { $TIME_EXACT ? do { require Time::HiRes; Time::HiRes::time () } : time };
		221	}
		222
		223	BEGIN {
		224	exact_time 0;
		225	}
169		226
170	AnyEvent::post_detect {	227	AnyEvent::post_detect {
171	*now = \&AE::now;	228	exact_time $TIME_EXACT;
172	};	229	};
173		230
174	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);	231	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);
175		232
176	# time, ctx, level, msg	233	# time, ctx, level, msg
…		…
195	? $level+0	252	? $level+0
196	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";	253	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";
197		254
198	my $mask = 1 << $level;	255	my $mask = 1 << $level;
199		256
200	my (%seen, @ctx, $now, $fmt);	257	my ($success, %seen, @ctx, $now, $fmt);
201		258
202	do	259	do
203	{	260	{
204	# skip if masked	261	# skip if masked
205	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {	262	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {
…		…
209	# now get raw message, unless we have it already	266	# now get raw message, unless we have it already
210	unless ($now) {	267	unless ($now) {
211	$format = $format->() if ref $format;	268	$format = $format->() if ref $format;
212	$format = sprintf $format, @args if @args;	269	$format = sprintf $format, @args if @args;
213	$format =~ s/\n$//;	270	$format =~ s/\n$//;
214	$now = AE::now;	271	$now = _ts;
215	};	272	};
216		273
217	# format msg	274	# format msg
218	my $str = $ctx->[4]	275	my $str = $ctx->[4]
219	? $ctx->[4]($now, $_[0], $level, $format)	276	? $ctx->[4]($now, $_[0], $level, $format)
220	: $fmt \|\|= _format $now, $_[0], $level, $format;	277	: ($fmt \|\|= _format $now, $_[0], $level, $format);
221		278
		279	$success = 1;
		280
222	$ctx->[3]($str);	281	$ctx->[3]($str)
		282	or push @ctx, values %{ $ctx->[2] }; # not consumed - propagate
		283	} else {
		284	push @ctx, values %{ $ctx->[2] }; # not masked - propagate
223	}	285	}
224
225	# not masked, not consumed - propagate to parent contexts
226	push @ctx, values %{ $ctx->[2] };
227	}	286	}
228	}	287	}
229	while $ctx = pop @ctx;	288	while $ctx = pop @ctx;
230		289
231	exit 1 if $level <= 1;	290	exit 1 if $level <= 1;
		291
		292	$success
232	}	293	}
233		294
234	sub log($$;@) {	295	sub log($$;@) {
235	_log	296	_log
236	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	297	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
…		…
240	AnyEvent::log = AE::log = \&log;	301	AnyEvent::log = AE::log = \&log;
241		302
242	=item $logger = AnyEvent::Log::logger $level[, \$enabled]	303	=item $logger = AnyEvent::Log::logger $level[, \$enabled]
243		304
244	Creates a code reference that, when called, acts as if the	305	Creates a code reference that, when called, acts as if the
245	C<AnyEvent::Log::log> function was called at this point with the givne	306	C<AnyEvent::Log::log> function was called at this point with the given
246	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with	307	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with
247	the C<AnyEvent::Log::log> function:	308	the C<AnyEvent::Log::log> function:
248		309
249	my $debug_log = AnyEvent::Log::logger "debug";	310	my $debug_log = AnyEvent::Log::logger "debug";
250		311
…		…
275	# and later in your program	336	# and later in your program
276	$debug_log->("yo, stuff here") if $debug;	337	$debug_log->("yo, stuff here") if $debug;
277		338
278	$debug and $debug_log->("123");	339	$debug and $debug_log->("123");
279		340
280	Note: currently the enabled var is always true - that will be fixed in a
281	future version :)
282
283	=cut	341	=cut
284		342
285	our %LOGGER;	343	our %LOGGER;
286		344
287	# re-assess logging status for all loggers	345	# re-assess logging status for all loggers
288	sub _reassess {	346	sub _reassess {
		347	local $SIG{__DIE__};
		348	my $die = sub { die };
		349
289	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {	350	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {
290	my ($ctx, $level, $renabled) = @$_;	351	my ($ctx, $level, $renabled) = @$_;
291		352
292	# to detect whether a message would be logged, we # actually	353	# 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	354	# try to log one and die. this isn't fast, but we can be
294	# sure that the logging decision is correct :)	355	# sure that the logging decision is correct :)
295		356
296	$$renabled = !eval {	357	$$renabled = !eval {
297	local $SIG{__DIE__};
298
299	_log $ctx, $level, sub { die };	358	_log $ctx, $level, $die;
300		359
301	1	360	1
302	};	361	};
303
304	$$renabled = 1; # TODO
305	}	362	}
306	}	363	}
307		364
308	sub _logger($;$) {	365	sub _logger {
309	my ($ctx, $level, $renabled) = @_;	366	my ($ctx, $level, $renabled) = @_;
310		367
311	$renabled \|\|= \my $enabled;
312
313	$$renabled = 1;	368	$$renabled = 1;
314		369
315	my $logger = [$ctx, $level, $renabled];	370	my $logger = [$ctx, $level, $renabled];
316		371
317	$LOGGER{$logger+0} = $logger;	372	$LOGGER{$logger+0} = $logger;
318		373
319	_reassess $logger+0;	374	_reassess $logger+0;
320		375
		376	require AnyEvent::Util;
321	my $guard = AnyEvent::Util::guard {	377	my $guard = AnyEvent::Util::guard (sub {
322	# "clean up"	378	# "clean up"
323	delete $LOGGER{$logger+0};	379	delete $LOGGER{$logger+0};
324	};	380	});
325		381
326	sub {	382	sub {
327	$guard if 0; # keep guard alive, but don't cause runtime overhead	383	$guard if 0; # keep guard alive, but don't cause runtime overhead
328		384
329	_log $ctx, $level, @_	385	_log $ctx, $level, @_
…		…
334	sub logger($;$) {	390	sub logger($;$) {
335	_logger	391	_logger
336	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	392	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
337	@_	393	@_
338	}	394	}
		395
		396	=item AnyEvent::Log::exact_time $on
		397
		398	By default, C<AnyEvent::Log> will use C<AE::now>, i.e. the cached
		399	eventloop time, for the log timestamps. After calling this function with a
		400	true value it will instead resort to C<AE::time>, i.e. fetch the current
		401	time on each log message. This only makes a difference for event loops
		402	that actually cache the time (such as L<EV> or L<AnyEvent::Loop>).
		403
		404	This setting can be changed at any time by calling this function.
		405
		406	Since C<AnyEvent::Log> has to work even before the L<AnyEvent> has been
		407	initialised, this switch will also decide whether to use C<CORE::time> or
		408	C<Time::HiRes::time> when logging a message before L<AnyEvent> becomes
		409	available.
339		410
340	=back	411	=back
341		412
342	=head1 LOGGING CONTEXTS	413	=head1 LOGGING CONTEXTS
343		414
…		…
356	timestamp, context, level and string message and formats it in the way	427	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	428	it should be logged) and a logging callback (which is responsible for
358	actually logging the formatted message and telling C<AnyEvent::Log>	429	actually logging the formatted message and telling C<AnyEvent::Log>
359	whether it has consumed the message, or whether it should be propagated).	430	whether it has consumed the message, or whether it should be propagated).
360		431
361	For propagation, a context can have any number of attached I<parent	432	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	433	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	434	masked by the logging callback returning true will be passed to all slave
364	contexts.	435	contexts.
365		436
366	Each call to a logging function will log the message at most once per	437	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	438	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.	439	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	443	By default, all logging contexts have an full set of log levels ("all"), a
373	disabled logging callback and the default formatting callback.	444	disabled logging callback and the default formatting callback.
374		445
375	Package contexts have the package name as logging title by default.	446	Package contexts have the package name as logging title by default.
376		447
377	They have exactly one parent - the context of the "parent" package. The	448	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	449	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>,	450	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
380	and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the	451	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	452	exception of the rule - just like the "parent" of any single-component
382	Perl is C<main>, the default parent of any toplevel package context is	453	package name in Perl is C<main>, the default slave of any top-level
383	C<AnyEvent::Log::Top>.	454	package context is C<$AnyEvent::Log::COLLECT>.
384		455
385	Since perl packages form only an approximate hierarchy, this parent	456	Since perl packages form only an approximate hierarchy, this slave
386	context can of course be removed.	457	context can of course be removed.
387		458
388	All other (anonymous) contexts have no parents and an empty title by	459	All other (anonymous) contexts have no slaves and an empty title by
389	default.	460	default.
390		461
391	When the module is loaded it creates the default context called	462	When the module is loaded it creates the C<$AnyEvent::Log::LOG> logging
392	C<AnyEvent::Log::Default>, which simply logs everything to STDERR and	463	context that simply logs everything via C<warn>, without propagating
393	doesn't propagate anything anywhere by default. The purpose of the default	464	anything anywhere by default. The purpose of this context is to provide
394	context is to provide a convenient place to override the global logging	465	a convenient place to override the global logging target or to attach
395	target or to attach additional log targets. It's not meant for filtering.	466	additional log targets. It's not meant for filtering.
396		467
397	It then creates the root context called C<AnyEvent::Log::Root> and	468	It then creates the C<$AnyEvent::Log::FILTER> context whose
398	sets its log level set to all levels up to the one specified by	469	purpose is to suppress all messages with priority higher
399	C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the default logging	470	than C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the
400	context to it. The purpose of the root context is to simply provide	471	C<$AnyEvent::Log::LOG> context to it. The purpose of the filter context
401	filtering according to some global log level.	472	is to simply provide filtering according to some global log level.
402		473
403	Finally it creates the toplevel package context called	474	Finally it creates the top-level package context C<$AnyEvent::Log::COLLECT>
404	C<AnyEvent::Log::Top> and attached the root context but otherwise leaves	475	and attaches the C<$AnyEvent::Log::FILTER> context to it, but otherwise
405	it at default config. It's purpose is simply to collect all log messages	476	leaves it at default config. Its purpose is simply to collect all log
406	system-wide.	477	messages system-wide.
407		478
408	These three special contexts can also be referred to by the names	479	The hierarchy is then:
409	C<AE::Log::Default>, C<AE::Log::Root> and C<AE::Log::Top>.
410		480
		481	any package, eventually -> $COLLECT -> $FILTER -> $LOG
		482
411	The effect of all this is that log messages, by default, wander up	483	The effect of all this is that log messages, by default, wander up to the
412	to the root context where log messages with lower priority then	484	C<$AnyEvent::Log::COLLECT> context where all messages normally end up,
		485	from there to C<$AnyEvent::Log::FILTER> where log messages with lower
413	C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered away and then to the	486	priority then C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered out and then
414	AnyEvent::Log::Default context to be logged to STDERR.	487	to the C<$AnyEvent::Log::LOG> context to be passed to C<warn>.
415		488
416	Splitting the top level context into three contexts makes it easy to set	489	This makes it easy to set a global logging level (by modifying $FILTER),
417	a global logging level (by modifying the root context), but still allow	490	but still allow other contexts to send, for example, their debug and trace
418	other contexts to log, for example, their debug and trace messages to the
419	default target despite the global logging level, or to attach additional	491	messages to the $LOG target despite the global logging level, or to attach
420	log targets that log messages, regardless of the global logging level.	492	additional log targets that log messages, regardless of the global logging
		493	level.
421		494
422	It also makes it easy to replace the default STDERR-logger by something	495	It also makes it easy to modify the default warn-logger ($LOG) to
423	that logs to a file, or to attach additional logging targets.	496	something that logs to a file, or to attach additional logging targets
		497	(such as loggign to a file) by attaching it to $FILTER.
424		498
425	=head2 CREATING/FINDING/DESTROYING CONTEXTS	499	=head2 CREATING/FINDING/DESTROYING CONTEXTS
426		500
427	=over 4	501	=over 4
428		502
…		…
450	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"	524	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"
451	}	525	}
452		526
453	=item AnyEvent::Log::reset	527	=item AnyEvent::Log::reset
454		528
455	Deletes all contexts and recreates the default hierarchy, i.e. resets the	529	Resets all package contexts and recreates the default hierarchy if
456	logging subsystem to defaults.	530	necessary, i.e. resets the logging subsystem to defaults, as much as
		531	possible. This process keeps references to contexts held by other parts of
		532	the program intact.
457		533
458	This can be used to implement config-file (re-)loading: before loading a	534	This can be used to implement config-file (re-)loading: before loading a
459	configuration, reset all contexts.	535	configuration, reset all contexts.
460		536
461	=cut	537	=cut
462		538
463	sub reset {	539	sub reset {
464	@$_ = () for values %CTX; # just to be sure - to kill circular logging dependencies	540	# hard to kill complex data structures
465	%CTX = ();	541	# we "recreate" all package loggers and reset the hierarchy
		542	while (my ($k, $v) = each %CTX) {
		543	@$v = ($k, (1 << 10) - 1 - 1, { });
466		544
467	my $default = ctx undef;	545	$v->attach ($k =~ /^(.+)::/ ? $CTX{$1} : $AnyEvent::Log::COLLECT);
468	$default->title ("AnyEvent::Log::Default");
469	$default->log_cb (sub {
470	print STDERR shift;
471	0
472	});	546	}
473	$CTX{"AnyEvent::Log::Default"} = $CTX{"AE::Log::Default"} = $default;
474		547
475	my $root = ctx undef;	548	@$_ = ($_->[0], (1 << 10) - 1 - 1)
		549	for $LOG, $FILTER, $COLLECT;
		550
		551	#$LOG->slaves;
476	$root->title ("AnyEvent::Log::Root");	552	$LOG->title ('$AnyEvent::Log::LOG');
		553	$LOG->log_to_warn;
		554
		555	$FILTER->slaves ($LOG);
		556	$FILTER->title ('$AnyEvent::Log::FILTER');
477	$root->level ($AnyEvent::VERBOSE);	557	$FILTER->level ($AnyEvent::VERBOSE);
478	$root->attach ($default);
479	$CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $root;
480		558
481	my $top = ctx undef;	559	$COLLECT->slaves ($FILTER);
482	$top->title ("AnyEvent::Log::Top");	560	$COLLECT->title ('$AnyEvent::Log::COLLECT');
483	$top->attach ($root);	561
484	$CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $top;	562	_reassess;
485	}	563	}
		564
		565	# create the default logger contexts
		566	$LOG = ctx undef;
		567	$FILTER = ctx undef;
		568	$COLLECT = ctx undef;
486		569
487	AnyEvent::Log::reset;	570	AnyEvent::Log::reset;
488		571
		572	# hello, CPAN, please catch me
489	package AnyEvent::Log::Default;	573	package AnyEvent::Log::LOG;
490	package AE::Log::Default;	574	package AE::Log::LOG;
		575	package AnyEvent::Log::FILTER;
		576	package AE::Log::FILTER;
		577	package AnyEvent::Log::COLLECT;
		578	package AE::Log::COLLECT;
		579
491	package AnyEvent::Log::Root;	580	package AnyEvent::Log::Ctx;
492	package AE::Log::Root;	581
493	package AnyEvent::Log::Top;	582	# 0 1 2 3 4
494	package AE::Log::Top;	583	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
		584
		585	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
		586
		587	This is a convenience constructor that makes it simpler to construct
		588	anonymous logging contexts.
		589
		590	Each key-value pair results in an invocation of the method of the same
		591	name as the key with the value as parameter, unless the value is an
		592	arrayref, in which case it calls the method with the contents of the
		593	array. The methods are called in the same order as specified.
		594
		595	Example: create a new logging context and set both the default logging
		596	level, some slave contexts and a logging callback.
		597
		598	$ctx = new AnyEvent::Log::Ctx
		599	title => "dubious messages",
		600	level => "error",
		601	log_cb => sub { print STDOUT shift; 0 },
		602	slaves => [$ctx1, $ctx, $ctx2],
		603	;
495		604
496	=back	605	=back
497		606
498	=cut	607	=cut
499		608
500	package AnyEvent::Log::Ctx;	609	sub new {
		610	my $class = shift;
501		611
502	# 0 1 2 3 4	612	my $ctx = AnyEvent::Log::ctx undef;
503	# [$title, $level, %$parents, &$logcb, &$fmtcb]	613
		614	while (@_) {
		615	my ($k, $v) = splice @_, 0, 2;
		616	$ctx->$k (ref $v eq "ARRAY" ? @$v : $v);
		617	}
		618
		619	bless $ctx, $class # do we really support subclassing, hmm?
		620	}
		621
504		622
505	=head2 CONFIGURING A LOG CONTEXT	623	=head2 CONFIGURING A LOG CONTEXT
506		624
507	The following methods can be used to configure the logging context.	625	The following methods can be used to configure the logging context.
508		626
…		…
602	AnyEvent::Log::_reassess;	720	AnyEvent::Log::_reassess;
603	}	721	}
604		722
605	=back	723	=back
606		724
607	=head3 PARENT CONTEXTS	725	=head3 SLAVE CONTEXTS
608		726
609	The following methods attach and detach another logging context to a	727	The following methods attach and detach another logging context to a
610	logging context.	728	logging context.
611		729
612	Log messages are propagated to all parent contexts, unless the logging	730	Log messages are propagated to all slave contexts, unless the logging
613	callback consumes the message.	731	callback consumes the message.
614		732
615	=over 4	733	=over 4
616		734
617	=item $ctx->attach ($ctx2[, $ctx3...])	735	=item $ctx->attach ($ctx2[, $ctx3...])
618		736
619	Attaches the given contexts as parents to this context. It is not an error	737	Attaches the given contexts as slaves to this context. It is not an error
620	to add a context twice (the second add will be ignored).	738	to add a context twice (the second add will be ignored).
621		739
622	A context can be specified either as package name or as a context object.	740	A context can be specified either as package name or as a context object.
623		741
624	=item $ctx->detach ($ctx2[, $ctx3...])	742	=item $ctx->detach ($ctx2[, $ctx3...])
625		743
626	Removes the given parents from this context - it's not an error to attempt	744	Removes the given slaves from this context - it's not an error to attempt
627	to remove a context that hasn't been added.	745	to remove a context that hasn't been added.
628		746
629	A context can be specified either as package name or as a context object.	747	A context can be specified either as package name or as a context object.
630		748
631	=item $ctx->parents ($ctx2[, $ctx3...])	749	=item $ctx->slaves ($ctx2[, $ctx3...])
632		750
633	Replaces all parents attached to this context by the ones given.	751	Replaces all slaves attached to this context by the ones given.
634		752
635	=cut	753	=cut
636		754
637	sub attach {	755	sub attach {
638	my $ctx = shift;	756	my $ctx = shift;
…		…
646		764
647	delete $ctx->[2]{$_+0}	765	delete $ctx->[2]{$_+0}
648	for map { AnyEvent::Log::ctx $_ } @_;	766	for map { AnyEvent::Log::ctx $_ } @_;
649	}	767	}
650		768
651	sub parents {	769	sub slaves {
652	undef $_[0][2];	770	undef $_[0][2];
653	&attach;	771	&attach;
654	}	772	}
655		773
656	=back	774	=back
657		775
658	=head3 MESSAGE LOGGING	776	=head3 LOG TARGETS
659		777
660	The following methods configure how the logging context actually does	778	The following methods configure how the logging context actually does
661	the logging (which consists of formatting the message and printing it or	779	the logging (which consists of formatting the message and printing it or
662	whatever it wants to do with it) and also allows you to log messages	780	whatever it wants to do with it).
663	directly to a context, without going via your package context.
664		781
665	=over 4	782	=over 4
666		783
667	=item $ctx->log_cb ($cb->($str))	784	=item $ctx->log_cb ($cb->($str)
668		785
669	Replaces the logging callback on the context (C<undef> disables the	786	Replaces the logging callback on the context (C<undef> disables the
670	logging callback).	787	logging callback).
671		788
672	The logging callback is responsible for handling formatted log messages	789	The logging callback is responsible for handling formatted log messages
673	(see C<fmt_cb> below) - normally simple text strings that end with a	790	(see C<fmt_cb> below) - normally simple text strings that end with a
674	newline (and are possibly multiline themselves).	791	newline (and are possibly multiline themselves).
675		792
676	It also has to return true iff it has consumed the log message, and false	793	It also has to return true iff it has consumed the log message, and false
677	if it hasn't. Consuming a message means that it will not be sent to any	794	if it hasn't. Consuming a message means that it will not be sent to any
678	parent context. When in doubt, return C<0> from your logging callback.	795	slave context. When in doubt, return C<0> from your logging callback.
679		796
680	Example: a very simple logging callback, simply dump the message to STDOUT	797	Example: a very simple logging callback, simply dump the message to STDOUT
681	and do not consume it.	798	and do not consume it.
682		799
683	$ctx->log_cb (sub { print STDERR shift; 0 });	800	$ctx->log_cb (sub { print STDERR shift; 0 });
…		…
691	your program.	808	your program.
692		809
693	$ctx->levels ("debug", "trace");	810	$ctx->levels ("debug", "trace");
694	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages	811	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages
695		812
696	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	813	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $orig_ctx, $level, $message))
697		814
698	Replaces the formatting callback on the context (C<undef> restores the	815	Replaces the formatting callback on the context (C<undef> restores the
699	default formatter).	816	default formatter).
700		817
701	The callback is passed the (possibly fractional) timestamp, the original	818	The callback is passed the (possibly fractional) timestamp, the original
702	logging context, the (numeric) logging level and the raw message string and needs to	819	logging context, the (numeric) logging level and the raw message string
703	return a formatted log message. In most cases this will be a string, but	820	and needs to return a formatted log message. In most cases this will be a
704	it could just as well be an array reference that just stores the values.	821	string, but it could just as well be an array reference that just stores
		822	the values.
		823
		824	If, for some reason, you want to use C<caller> to find out more baout the
		825	logger then you should walk up the call stack until you are no longer
		826	inside the C<AnyEvent::Log> package.
705		827
706	Example: format just the raw message, with numeric log level in angle	828	Example: format just the raw message, with numeric log level in angle
707	brackets.	829	brackets.
708		830
709	$ctx->fmt_cb (sub {	831	$ctx->fmt_cb (sub {
…		…
726	"$msg->[3]";	848	"$msg->[3]";
727		849
728	0	850	0
729	});	851	});
730		852
		853	=item $ctx->log_to_warn
		854
		855	Sets the C<log_cb> to simply use C<CORE::warn> to report any messages
		856	(usually this logs to STDERR).
		857
		858	=item $ctx->log_to_file ($path)
		859
		860	Sets the C<log_cb> to log to a file (by appending), unbuffered.
		861
		862	=item $ctx->log_to_path ($path)
		863
		864	Same as C<< ->log_to_file >>, but opens the file for each message. This
		865	is much slower, but allows you to change/move/rename/delete the file at
		866	basically any time.
		867
		868	Needless(?) to say, if you do not want to be bitten by some evil person
		869	calling C<chdir>, the path should be absolute. Doesn't help with
		870	C<chroot>, but hey...
		871
		872	=item $ctx->log_to_syslog ([$facility])
		873
		874	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and
		875	all the others in the obvious way. If specified, then the C<$facility> is
		876	used as the facility (C<user>, C<auth>, C<local0> and so on). The default
		877	facility is C<user>.
		878
		879	Note that this function also sets a C<fmt_cb> - the logging part requires
		880	an array reference with [$level, $str] as input.
		881
731	=cut	882	=cut
732		883
733	sub log_cb {	884	sub log_cb {
734	my ($ctx, $cb) = @_;	885	my ($ctx, $cb) = @_;
735		886
…		…
740	my ($ctx, $cb) = @_;	891	my ($ctx, $cb) = @_;
741		892
742	$ctx->[4] = $cb;	893	$ctx->[4] = $cb;
743	}	894	}
744		895
		896	sub log_to_warn {
		897	my ($ctx, $path) = @_;
		898
		899	$ctx->log_cb (sub {
		900	warn shift;
		901	0
		902	});
		903	}
		904
		905	sub log_to_file {
		906	my ($ctx, $path) = @_;
		907
		908	open my $fh, ">>", $path
		909	or die "$path: $!";
		910
		911	$ctx->log_cb (sub {
		912	syswrite $fh, shift;
		913	0
		914	});
		915	}
		916
		917	sub log_to_path {
		918	my ($ctx, $path) = @_;
		919
		920	$ctx->log_cb (sub {
		921	open my $fh, ">>", $path
		922	or die "$path: $!";
		923
		924	syswrite $fh, shift;
		925	0
		926	});
		927	}
		928
		929	sub log_to_syslog {
		930	my ($ctx, $facility) = @_;
		931
		932	require Sys::Syslog;
		933
		934	$ctx->fmt_cb (sub {
		935	my $str = $_[3];
		936	$str =~ s/\n(?=.)/\n+ /g;
		937
		938	[$_[2], "($_[1][0]) $str"]
		939	});
		940
		941	$facility \|\|= "user";
		942
		943	$ctx->log_cb (sub {
		944	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;
		945
		946	Sys::Syslog::syslog ("$facility\|" . ($lvl - 1), $_)
		947	for split /\n/, $_[0][1];
		948
		949	0
		950	});
		951	}
		952
		953	=back
		954
		955	=head3 MESSAGE LOGGING
		956
		957	These methods allow you to log messages directly to a context, without
		958	going via your package context.
		959
		960	=over 4
		961
745	=item $ctx->log ($level, $msg[, @params])	962	=item $ctx->log ($level, $msg[, @params])
746		963
747	Same as C<AnyEvent::Log::log>, but uses the given context as log context.	964	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
748		965
749	=item $logger = $ctx->logger ($level[, \$enabled])	966	=item $logger = $ctx->logger ($level[, \$enabled])
…		…
754	=cut	971	=cut
755		972
756	*log = \&AnyEvent::Log::_log;	973	*log = \&AnyEvent::Log::_log;
757	*logger = \&AnyEvent::Log::_logger;	974	*logger = \&AnyEvent::Log::_logger;
758		975
		976	=back
		977
		978	=cut
		979
		980	package AnyEvent::Log;
		981
		982	=head1 CONFIGURATION VIA $ENV{PERL_ANYEVENT_LOG}
		983
		984	Logging can also be configured by setting the environment variable
		985	C<PERL_ANYEVENT_LOG> (or C<AE_LOG>).
		986
		987	The value consists of one or more logging context specifications separated
		988	by C<:> or whitespace. Each logging specification in turn starts with a
		989	context name, followed by C<=>, followed by zero or more comma-separated
		990	configuration directives, here are some examples:
		991
		992	# set default logging level
		993	filter=warn
		994
		995	# log to file instead of to stderr
		996	log=file=/tmp/mylog
		997
		998	# log to file in addition to stderr
		999	log=+%file:%file=file=/tmp/mylog
		1000
		1001	# enable debug log messages, log warnings and above to syslog
		1002	filter=debug:log=+%warnings:%warnings=warn,syslog=LOG_LOCAL0
		1003
		1004	# log trace messages (only) from AnyEvent::Debug to file
		1005	AnyEvent::Debug=+%trace:%trace=only,trace,file=/tmp/tracelog
		1006
		1007	A context name in the log specification can be any of the following:
		1008
		1009	=over 4
		1010
		1011	=item C<collect>, C<filter>, C<log>
		1012
		1013	Correspond to the three predefined C<$AnyEvent::Log::COLLECT>,
		1014	C<AnyEvent::Log::FILTER> and C<$AnyEvent::Log::LOG> contexts.
		1015
		1016	=item C<%name>
		1017
		1018	Context names starting with a C<%> are anonymous contexts created when the
		1019	name is first mentioned. The difference to package contexts is that by
		1020	default they have no attached slaves.
		1021
		1022	=item a perl package name
		1023
		1024	Any other string references the logging context associated with the given
		1025	Perl C<package>. In the unlikely case where you want to specify a package
		1026	context that matches on of the other context name forms, you can add a
		1027	C<::> to the package name to force interpretation as a package.
		1028
		1029	=back
		1030
		1031	The configuration specifications can be any number of the following:
		1032
		1033	=over 4
		1034
		1035	=item C<stderr>
		1036
		1037	Configures the context to use Perl's C<warn> function (which typically
		1038	logs to C<STDERR>). Works like C<log_to_warn>.
		1039
		1040	=item C<file=>I<path>
		1041
		1042	Configures the context to log to a file with the given path. Works like
		1043	C<log_to_file>.
		1044
		1045	=item C<path=>I<path>
		1046
		1047	Configures the context to log to a file with the given path. Works like
		1048	C<log_to_path>.
		1049
		1050	=item C<syslog> or C<syslog=>I<expr>
		1051
		1052	Configures the context to log to syslog. If I<expr> is given, then it is
		1053	evaluated in the L<Sys::Syslog> package, so you could use:
		1054
		1055	log=syslog=LOG_LOCAL0
		1056
		1057	=item C<nolog>
		1058
		1059	Configures the context to not log anything by itself, which is the
		1060	default. Same as C<< $ctx->log_cb (undef) >>.
		1061
		1062	=item C<0> or C<off>
		1063
		1064	Sets the logging level of the context ot C<0>, i.e. all messages will be
		1065	filtered out.
		1066
		1067	=item C<all>
		1068
		1069	Enables all logging levels, i.e. filtering will effectively be switched
		1070	off (the default).
		1071
		1072	=item C<only>
		1073
		1074	Disables all logging levels, and changes the interpretation of following
		1075	level specifications to enable the specified level only.
		1076
		1077	Example: only enable debug messages for a context.
		1078
		1079	context=only,debug
		1080
		1081	=item C<except>
		1082
		1083	Enables all logging levels, and changes the interpretation of following
		1084	level specifications to disable that level. Rarely used.
		1085
		1086	Example: enable all logging levels except fatal and trace (this is rather
		1087	nonsensical).
		1088
		1089	filter=exept,fatal,trace
		1090
		1091	=item C<level>
		1092
		1093	Enables all logging levels, and changes the interpretation of following
		1094	level specifications to be "that level or any higher priority
		1095	message". This is the default.
		1096
		1097	Example: log anything at or above warn level.
		1098
		1099	filter=warn
		1100
		1101	# or, more verbose
		1102	filter=only,level,warn
		1103
		1104	=item C<1>..C<9> or a logging level name (C<error>, C<debug> etc.)
		1105
		1106	A numeric loglevel or the name of a loglevel will be interpreted according
		1107	to the most recent C<only>, C<except> or C<level> directive. By default,
		1108	specifying a logging level enables that and any higher priority messages.
		1109
		1110	=item C<+>I<context>
		1111
		1112	Attaches the named context as slave to the context.
		1113
		1114	=item C<+>
		1115
		1116	A line C<+> detaches all contexts, i.e. clears the slave list from the
		1117	context. Anonymous (C<%name>) contexts have no attached slaves by default,
		1118	but package contexts have the parent context as slave by default.
		1119
		1120	Example: log messages from My::Module to a file, do not send them to the
		1121	default log collector.
		1122
		1123	My::Module=+,file=/tmp/mymodulelog
		1124
		1125	=back
		1126
		1127	Any character can be escaped by prefixing it with a C<\> (backslash), as
		1128	usual, so to log to a file containing a comma, colon, backslash and some
		1129	spaces in the filename, you would do this:
		1130
		1131	PERL_ANYEVENT_LOG='log=file=/some\ \:file\ with\,\ \\-escapes'
		1132
		1133	Since whitespace (which includes newlines) is allowed, it is fine to
		1134	specify multiple lines in C<PERL_ANYEVENT_LOG>, e.g.:
		1135
		1136	PERL_ANYEVENT_LOG="
		1137	filter=warn
		1138	AnyEvent::Debug=+%trace
		1139	%trace=only,trace,+log
		1140	" myprog
		1141
		1142	Also, in the unlikely case when you want to concatenate specifications,
		1143	use whitespace as separator, as C<::> will be interpreted as part of a
		1144	module name, an empty spec with two separators:
		1145
		1146	PERL_ANYEVENT_LOG="$PERL_ANYEVENT_LOG MyMod=debug"
		1147
		1148	=cut
		1149
		1150	for (my $spec = $ENV{PERL_ANYEVENT_LOG}) {
		1151	my %anon;
		1152
		1153	my $pkg = sub {
		1154	$_[0] eq "log" ? $LOG
		1155	: $_[0] eq "filter" ? $FILTER
		1156	: $_[0] eq "collect" ? $COLLECT
		1157	: $_[0] =~ /^%(.+)$/ ? ($anon{$1} \|\|= ctx undef)
		1158	: $_[0] =~ /^(.*?)(?:::)?$/ ? ctx "$1" # egad :/
		1159	: die # never reached?
		1160	};
		1161
		1162	/\G[[:space:]]+/gc; # skip initial whitespace
		1163
		1164	while (/\G((?:[^:=[:space:]]+\|::\|\\.)+)=/gc) {
		1165	my $ctx = $pkg->($1);
		1166	my $level = "level";
		1167
		1168	while (/\G((?:[^,:[:space:]]+\|::\|\\.)+)/gc) {
		1169	for ("$1") {
		1170	if ($_ eq "stderr" ) { $ctx->log_to_warn;
		1171	} elsif (/^file=(.+)/ ) { $ctx->log_to_file ("$1");
		1172	} elsif (/^path=(.+)/ ) { $ctx->log_to_path ("$1");
		1173	} elsif (/syslog(?:=(.*))?/ ) { require Sys::Syslog; $ctx->log_to_syslog ($1);
		1174	} elsif ($_ eq "nolog" ) { $ctx->log_cb (undef);
		1175	} elsif (/^\+(.+)$/ ) { $ctx->attach ($pkg->("$1"));
		1176	} elsif ($_ eq "+" ) { $ctx->slaves;
		1177	} elsif ($_ eq "off" or $_ eq "0") { $ctx->level (0);
		1178	} elsif ($_ eq "all" ) { $ctx->level ("all");
		1179	} elsif ($_ eq "level" ) { $ctx->level ("all"); $level = "level";
		1180	} elsif ($_ eq "only" ) { $ctx->level ("off"); $level = "enable";
		1181	} elsif ($_ eq "except" ) { $ctx->level ("all"); $level = "disable";
		1182	} elsif (/^\d$/ ) { $ctx->$level ($_);
		1183	} elsif (exists $STR2LEVEL{$_} ) { $ctx->$level ($_);
		1184	} else { die "PERL_ANYEVENT_LOG ($spec): parse error at '$_'\n";
		1185	}
		1186	}
		1187
		1188	/\G,/gc or last;
		1189	}
		1190
		1191	/\G[:[:space:]]+/gc or last;
		1192	}
		1193
		1194	/\G[[:space:]]+/gc; # skip trailing whitespace
		1195
		1196	if (/\G(.+)/g) {
		1197	die "PERL_ANYEVENT_LOG ($spec): parse error at '$1'\n";
		1198	}
		1199	}
		1200
759	1;	1201	1;
		1202
		1203	=head1 EXAMPLES
		1204
		1205	This section shows some common configurations, both as code, and as
		1206	C<PERL_ANYEVENT_LOG> string.
		1207
		1208	=over 4
		1209
		1210	=item Setting the global logging level.
		1211
		1212	Either put C<PERL_ANYEVENT_VERBOSE=><number> into your environment before
		1213	running your program, use C<PERL_ANYEVENT_LOG> or modify the log level of
		1214	the root context at runtime:
		1215
		1216	PERL_ANYEVENT_VERBOSE=5 ./myprog
		1217
		1218	PERL_ANYEVENT_LOG=log=warn
		1219
		1220	$AnyEvent::Log::FILTER->level ("warn");
		1221
		1222	=item Append all messages to a file instead of sending them to STDERR.
		1223
		1224	This is affected by the global logging level.
		1225
		1226	$AnyEvent::Log::LOG->log_to_file ($path);
		1227
		1228	PERL_ANYEVENT_LOG=log=file=/some/path
		1229
		1230	=item Write all messages with priority C<error> and higher to a file.
		1231
		1232	This writes them only when the global logging level allows it, because
		1233	it is attached to the default context which is invoked I<after> global
		1234	filtering.
		1235
		1236	$AnyEvent::Log::FILTER->attach
		1237	new AnyEvent::Log::Ctx log_to_file => $path);
		1238
		1239	PERL_ANYEVENT_LOG=filter=+%filelogger:%filelogger=file=/some/path
		1240
		1241	This writes them regardless of the global logging level, because it is
		1242	attached to the toplevel context, which receives all messages I<before>
		1243	the global filtering.
		1244
		1245	$AnyEvent::Log::COLLECT->attach (
		1246	new AnyEvent::Log::Ctx log_to_file => $path);
		1247
		1248	PERL_ANYEVENT_LOG=%filelogger=file=/some/path:collect=+%filelogger
		1249
		1250	In both cases, messages are still written to STDERR.
		1251
		1252	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
		1253
		1254	Attach the C<$AnyEvent::Log::LOG> context to the C<AnyEvent::Debug>
		1255	context - this simply circumvents the global filtering for trace messages.
		1256
		1257	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
		1258	$debug->attach ($AnyEvent::Log::LOG);
		1259
		1260	PERL_ANYEVENT_LOG=AnyEvent::Debug=+log
		1261
		1262	This of course works for any package, not just L<AnyEvent::Debug>, but
		1263	assumes the log level for AnyEvent::Debug hasn't been changed from the
		1264	default.
760		1265
761	=back	1266	=back
762		1267
763	=head1 AUTHOR	1268	=head1 AUTHOR
764		1269
765	Marc Lehmann <schmorp@schmorp.de>	1270	Marc Lehmann <schmorp@schmorp.de>
766	http://home.schmorp.de/	1271	http://home.schmorp.de/
767		1272
768	=cut	1273	=cut
		1274

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents): Revision 1.11 by root, Sat Aug 20 01:03:09 2011 UTC vs. Revision 1.41 by root, Thu Sep 1 04:07:18 2011 UTC

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.11 by root, Sat Aug 20 01:03:09 2011 UTC vs.
Revision 1.41 by root, Thu Sep 1 04:07:18 2011 UTC