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

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.17 by root, Sat Aug 20 02:21:53 2011 UTC vs.
Revision 1.43 by root, Mon Sep 5 07:21:54 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 errors and higher only	30	# set logging for the current package to errors and higher only
26	AnyEvent::Log::ctx->level ("error");	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::Root->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,
		37	# regardless of (most) other settings
		38	$AnyEvent::Log::COLLECT->attach (new AnyEvent::Log::Ctx
		39	level => "critical",
		40	log_to_syslog => "user",
		41	);
32		42
33	=head1 DESCRIPTION	43	=head1 DESCRIPTION
34		44
35	This module implements a relatively simple "logging framework". It doesn't	45	This module implements a relatively simple "logging framework". It doesn't
36	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
37	AnyEvent - AnyEvent simply creates logging messages internally, and this	47	AnyEvent - AnyEvent simply creates logging messages internally, and this
38	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
39	using it from other modules as well.	49	using it from other modules as well.
40		50
41	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
42	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
43	starting your program, or change the logging level at runtime with	53	before starting your program, or change the logging level at runtime with
44	something like:	54	something like:
45		55
46	use AnyEvent;	56	use AnyEvent::Log;
47	(AnyEvent::Log::ctx "")->level ("info");	57	$AnyEvent::Log::FILTER->level ("info");
48		58
49	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),
50	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
51	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
52	targets, or being able to log into a database.	62	targets, or being able to log into a database.
53		63
		64	The module is also usable before AnyEvent itself is initialised, in which
		65	case some of the functionality might be reduced.
		66
54	The amount of documentation might indicate otherwise, but the module is	67	The amount of documentation might indicate otherwise, but the runtime part
55	still just 240 lines or so.	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 system unusable, aborts program!
		81	2 alert failure in primary system
		82	3 critical crit failure in backup system
		83	4 error err die non-urgent program errors, a bug
		84	5 warn warning possible problem, not necessarily error
		85	6 note notice unusual conditions
		86	7 info normal messages, no action required
		87	8 debug debugging messages for development
		88	9 trace copious tracing output
		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. The NOTE column tries to provide some
		94	rationale on how to chose a logging level.
		95
		96	As a rough guideline, levels 1..3 are primarily meant for users of
		97	the program (admins, staff), and are the only logged to STDERR by
		98	default. Levels 4..6 are meant for users and developers alike, while
		99	levels 7..9 are usually meant for developers.
		100
		101	You can normally only log a single message at highest priority level
		102	(C<1>, C<fatal>), because logging a fatal message will also quit the
		103	program - so use it sparingly :)
		104
		105	Some methods also offer some extra levels, such as C<0>, C<off>, C<none>
		106	or C<all> - these are only valid in the methods they are documented for.
56		107
57	=head1 LOGGING FUNCTIONS	108	=head1 LOGGING FUNCTIONS
58		109
59	These functions allow you to log messages. They always use the caller's	110	These functions allow you to log messages. They always use the caller's
60	package as a "logging module/source". Also, the main logging function is	111	package as a "logging context". Also, the main logging function C<log> is
61	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is	112	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is
62	loaded.	113	loaded.
63		114
64	=over 4	115	=over 4
65		116
…		…
69		120
70	use Carp ();	121	use Carp ();
71	use POSIX ();	122	use POSIX ();
72		123
73	use AnyEvent (); BEGIN { AnyEvent::common_sense }	124	use AnyEvent (); BEGIN { AnyEvent::common_sense }
74	use AnyEvent::Util ();	125	#use AnyEvent::Util (); need to load this in a delayed fashion, as it uses AE::log
75		126
76	our $VERSION = $AnyEvent::VERSION;	127	our $VERSION = $AnyEvent::VERSION;
		128
		129	our ($COLLECT, $FILTER, $LOG);
77		130
78	our ($now_int, $now_str1, $now_str2);	131	our ($now_int, $now_str1, $now_str2);
79		132
80	# Format Time, not public - yet?	133	# Format Time, not public - yet?
81	sub ft($) {	134	sub ft($) {
…		…
86	if $now_int != $i;	139	if $now_int != $i;
87		140
88	"$now_str1$f$now_str2"	141	"$now_str1$f$now_str2"
89	}	142	}
90		143
91	our %CTX; # all logging contexts	144	our %CTX; # all package contexts
92		145
93	# creates a default package context object for the given package	146	# creates a default package context object for the given package
94	sub _pkg_ctx($) {	147	sub _pkg_ctx($) {
95	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";	148	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";
96		149
97	# link "parent" package	150	# link "parent" package
98	my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "AE::Log::Top";	151	my $parent = $_[0] =~ /^(.+)::/
		152	? $CTX{$1} \|\|= &_pkg_ctx ("$1")
		153	: $COLLECT;
99		154
100	$pkg = $CTX{$pkg} \|\|= &_pkg_ctx ($pkg);
101	$ctx->[2]{$pkg+0} = $pkg;	155	$ctx->[2]{$parent+0} = $parent;
102		156
103	$ctx	157	$ctx
104	}	158	}
105		159
106	=item AnyEvent::Log::log $level, $msg[, @args]	160	=item AnyEvent::Log::log $level, $msg[, @args]
107		161
108	Requests logging of the given C<$msg> with the given log level (1..9).	162	Requests logging of the given C<$msg> with the given log level, and
109	You can also use the following strings as log level: C<fatal> (1),	163	returns true if the message was logged I<somewhere>.
110	C<alert> (2), C<critical> (3), C<error> (4), C<warn> (5), C<note> (6),
111	C<info> (7), C<debug> (8), C<trace> (9).
112		164
113	For C<fatal> log levels, the program will abort.	165	For loglevel C<fatal>, the program will abort.
114		166
115	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the	167	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the
116	C<$msg> is interpreted as an sprintf format string.	168	C<$msg> is interpreted as an sprintf format string.
117		169
118	The C<$msg> should not end with C<\n>, but may if that is convenient for	170	The C<$msg> should not end with C<\n>, but may if that is convenient for
…		…
122	supposed to return the message. It will be called only then the message	174	supposed to return the message. It will be called only then the message
123	actually gets logged, which is useful if it is costly to create the	175	actually gets logged, which is useful if it is costly to create the
124	message in the first place.	176	message in the first place.
125		177
126	Whether the given message will be logged depends on the maximum log level	178	Whether the given message will be logged depends on the maximum log level
127	and the caller's package.	179	and the caller's package. The return value can be used to ensure that
		180	messages or not "lost" - for example, when L<AnyEvent::Debug> detects a
		181	runtime error it tries to log it at C<die> level, but if that message is
		182	lost it simply uses warn.
128		183
129	Note that you can (and should) call this function as C<AnyEvent::log> or	184	Note that you can (and should) call this function as C<AnyEvent::log> or
130	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't	185	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't
131	need any additional functionality), as those functions will load the	186	need any additional functionality), as those functions will load the
132	logging module on demand only. They are also much shorter to write.	187	logging module on demand only. They are also much shorter to write.
…		…
149		204
150	=cut	205	=cut
151		206
152	# also allow syslog equivalent names	207	# also allow syslog equivalent names
153	our %STR2LEVEL = (	208	our %STR2LEVEL = (
154	fatal => 1, emerg => 1,	209	fatal => 1, emerg => 1, exit => 1,
155	alert => 2,	210	alert => 2,
156	critical => 3, crit => 3,	211	critical => 3, crit => 3,
157	error => 4, err => 4,	212	error => 4, err => 4, die => 4,
158	warn => 5, warning => 5,	213	warn => 5, warning => 5,
159	note => 6, notice => 6,	214	note => 6, notice => 6,
160	info => 7,	215	info => 7,
161	debug => 8,	216	debug => 8,
162	trace => 9,	217	trace => 9,
163	);	218	);
164		219
165	sub now () { time }	220	our $TIME_EXACT;
		221
		222	sub exact_time($) {
		223	$TIME_EXACT = shift;
		224	*_ts = $AnyEvent::MODEL
		225	? $TIME_EXACT ? \&AE::now : \&AE::time
		226	: sub () { $TIME_EXACT ? do { require Time::HiRes; Time::HiRes::time () } : time };
		227	}
		228
		229	BEGIN {
		230	exact_time 0;
		231	}
166		232
167	AnyEvent::post_detect {	233	AnyEvent::post_detect {
168	*now = \&AE::now;	234	exact_time $TIME_EXACT;
169	};	235	};
170		236
171	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);	237	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);
172		238
173	# time, ctx, level, msg	239	# time, ctx, level, msg
…		…
183	}	249	}
184		250
185	join "", @res	251	join "", @res
186	}	252	}
187		253
		254	sub fatal_exit() {
		255	exit 1;
		256	}
		257
188	sub _log {	258	sub _log {
189	my ($ctx, $level, $format, @args) = @_;	259	my ($ctx, $level, $format, @args) = @_;
190		260
191	$level = $level > 0 && $level <= 9	261	$level = $level > 0 && $level <= 9
192	? $level+0	262	? $level+0
193	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";	263	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";
194		264
195	my $mask = 1 << $level;	265	my $mask = 1 << $level;
196		266
197	my (%seen, @ctx, $now, $fmt);	267	my ($success, %seen, @ctx, $now, $fmt);
198		268
199	do	269	do
200	{	270	{
201	# skip if masked	271	# skip if masked
202	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {	272	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {
…		…
206	# now get raw message, unless we have it already	276	# now get raw message, unless we have it already
207	unless ($now) {	277	unless ($now) {
208	$format = $format->() if ref $format;	278	$format = $format->() if ref $format;
209	$format = sprintf $format, @args if @args;	279	$format = sprintf $format, @args if @args;
210	$format =~ s/\n$//;	280	$format =~ s/\n$//;
211	$now = AE::now;	281	$now = _ts;
212	};	282	};
213		283
214	# format msg	284	# format msg
215	my $str = $ctx->[4]	285	my $str = $ctx->[4]
216	? $ctx->[4]($now, $_[0], $level, $format)	286	? $ctx->[4]($now, $_[0], $level, $format)
217	: $fmt \|\|= _format $now, $_[0], $level, $format;	287	: ($fmt \|\|= _format $now, $_[0], $level, $format);
218		288
		289	$success = 1;
		290
219	$ctx->[3]($str);	291	$ctx->[3]($str)
		292	or push @ctx, values %{ $ctx->[2] }; # not consumed - propagate
		293	} else {
		294	push @ctx, values %{ $ctx->[2] }; # not masked - propagate
220	}	295	}
221
222	# not masked, not consumed - propagate to parent contexts
223	push @ctx, values %{ $ctx->[2] };
224	}	296	}
225	}	297	}
226	while $ctx = pop @ctx;	298	while $ctx = pop @ctx;
227		299
228	exit 1 if $level <= 1;	300	fatal_exit if $level <= 1;
		301
		302	$success
229	}	303	}
230		304
231	sub log($$;@) {	305	sub log($$;@) {
232	_log	306	_log
233	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	307	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
234	@_;	308	@_;
235	}	309	}
236		310
237	AnyEvent::log = AE::log = \&log;
238
239	=item $logger = AnyEvent::Log::logger $level[, \$enabled]	311	=item $logger = AnyEvent::Log::logger $level[, \$enabled]
240		312
241	Creates a code reference that, when called, acts as if the	313	Creates a code reference that, when called, acts as if the
242	C<AnyEvent::Log::log> function was called at this point with the givne	314	C<AnyEvent::Log::log> function was called at this point with the given
243	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with	315	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with
244	the C<AnyEvent::Log::log> function:	316	the C<AnyEvent::Log::log> function:
245		317
246	my $debug_log = AnyEvent::Log::logger "debug";	318	my $debug_log = AnyEvent::Log::logger "debug";
247		319
…		…
307		379
308	$LOGGER{$logger+0} = $logger;	380	$LOGGER{$logger+0} = $logger;
309		381
310	_reassess $logger+0;	382	_reassess $logger+0;
311		383
		384	require AnyEvent::Util unless $AnyEvent::Util::VERSION;
312	my $guard = AnyEvent::Util::guard {	385	my $guard = AnyEvent::Util::guard (sub {
313	# "clean up"	386	# "clean up"
314	delete $LOGGER{$logger+0};	387	delete $LOGGER{$logger+0};
315	};	388	});
316		389
317	sub {	390	sub {
318	$guard if 0; # keep guard alive, but don't cause runtime overhead	391	$guard if 0; # keep guard alive, but don't cause runtime overhead
319		392
320	_log $ctx, $level, @_	393	_log $ctx, $level, @_
…		…
325	sub logger($;$) {	398	sub logger($;$) {
326	_logger	399	_logger
327	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	400	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
328	@_	401	@_
329	}	402	}
		403
		404	=item AnyEvent::Log::exact_time $on
		405
		406	By default, C<AnyEvent::Log> will use C<AE::now>, i.e. the cached
		407	eventloop time, for the log timestamps. After calling this function with a
		408	true value it will instead resort to C<AE::time>, i.e. fetch the current
		409	time on each log message. This only makes a difference for event loops
		410	that actually cache the time (such as L<EV> or L<AnyEvent::Loop>).
		411
		412	This setting can be changed at any time by calling this function.
		413
		414	Since C<AnyEvent::Log> has to work even before the L<AnyEvent> has been
		415	initialised, this switch will also decide whether to use C<CORE::time> or
		416	C<Time::HiRes::time> when logging a message before L<AnyEvent> becomes
		417	available.
330		418
331	=back	419	=back
332		420
333	=head1 LOGGING CONTEXTS	421	=head1 LOGGING CONTEXTS
334		422
…		…
347	timestamp, context, level and string message and formats it in the way	435	timestamp, context, level and string message and formats it in the way
348	it should be logged) and a logging callback (which is responsible for	436	it should be logged) and a logging callback (which is responsible for
349	actually logging the formatted message and telling C<AnyEvent::Log>	437	actually logging the formatted message and telling C<AnyEvent::Log>
350	whether it has consumed the message, or whether it should be propagated).	438	whether it has consumed the message, or whether it should be propagated).
351		439
352	For propagation, a context can have any number of attached I<parent	440	For propagation, a context can have any number of attached I<slave
353	contexts>. Any message that is neither masked by the logging mask nor	441	contexts>. Any message that is neither masked by the logging mask nor
354	masked by the logging callback returning true will be passed to all parent	442	masked by the logging callback returning true will be passed to all slave
355	contexts.	443	contexts.
356		444
357	Each call to a logging function will log the message at most once per	445	Each call to a logging function will log the message at most once per
358	context, so it does not matter (much) if there are cycles or if the	446	context, so it does not matter (much) if there are cycles or if the
359	message can arrive at the same context via multiple paths.	447	message can arrive at the same context via multiple paths.
…		…
363	By default, all logging contexts have an full set of log levels ("all"), a	451	By default, all logging contexts have an full set of log levels ("all"), a
364	disabled logging callback and the default formatting callback.	452	disabled logging callback and the default formatting callback.
365		453
366	Package contexts have the package name as logging title by default.	454	Package contexts have the package name as logging title by default.
367		455
368	They have exactly one parent - the context of the "parent" package. The	456	They have exactly one slave - the context of the "parent" package. The
369	parent package is simply defined to be the package name without the last	457	parent package is simply defined to be the package name without the last
370	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,	458	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
371	and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the	459	and C<AnyEvent> becomes ... C<$AnyEvent::Log::COLLECT> which is the
372	exception of the rule - just like the parent of any package name in	460	exception of the rule - just like the "parent" of any single-component
373	Perl is C<main>, the default parent of any top-level package context is	461	package name in Perl is C<main>, the default slave of any top-level
374	C<AnyEvent::Log::Top>.	462	package context is C<$AnyEvent::Log::COLLECT>.
375		463
376	Since perl packages form only an approximate hierarchy, this parent	464	Since perl packages form only an approximate hierarchy, this slave
377	context can of course be removed.	465	context can of course be removed.
378		466
379	All other (anonymous) contexts have no parents and an empty title by	467	All other (anonymous) contexts have no slaves and an empty title by
380	default.	468	default.
381		469
382	When the module is loaded it creates the default context called	470	When the module is loaded it creates the C<$AnyEvent::Log::LOG> logging
383	C<AnyEvent::Log::Default> (also stored in C<$AnyEvent::Log::Default>),	471	context that simply logs everything via C<warn>, without propagating
384	which simply logs everything via C<warn> and doesn't propagate anything
385	anywhere by default. The purpose of the default context is to provide	472	anything anywhere by default. The purpose of this context is to provide
386	a convenient place to override the global logging target or to attach	473	a convenient place to override the global logging target or to attach
387	additional log targets. It's not meant for filtering.	474	additional log targets. It's not meant for filtering.
388		475
389	It then creates the root context called C<AnyEvent::Log::Root> (also	476	It then creates the C<$AnyEvent::Log::FILTER> context whose
390	stored in C<$AnyEvent::Log::Root>) and sets its log level set to all	477	purpose is to suppress all messages with priority higher
391	levels up to the one specified by C<$ENV{PERL_ANYEVENT_VERBOSE}>. It	478	than C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the
392	then attached the default logging context to it. The purpose of the root	479	C<$AnyEvent::Log::LOG> context to it. The purpose of the filter context
393	context is to simply provide filtering according to some global log level.	480	is to simply provide filtering according to some global log level.
394		481
395	Finally it creates the top-level package context called	482	Finally it creates the top-level package context C<$AnyEvent::Log::COLLECT>
396	C<AnyEvent::Log::Top> (also stored in, you might have guessed,	483	and attaches the C<$AnyEvent::Log::FILTER> context to it, but otherwise
397	C<$AnyEvent::Log::Top>) and attached the root context but otherwise leaves
398	it at default config. It's purpose is simply to collect all log messages	484	leaves it at default config. Its purpose is simply to collect all log
399	system-wide.	485	messages system-wide.
400		486
401	These three special contexts can also be referred to by the	487	The hierarchy is then:
402	package/context names C<AE::Log::Default>, C<AE::Log::Root> and
403	C<AE::Log::Top>.
404		488
		489	any package, eventually -> $COLLECT -> $FILTER -> $LOG
		490
405	The effect of all this is that log messages, by default, wander up	491	The effect of all this is that log messages, by default, wander up to the
406	to the root context where log messages with lower priority then	492	C<$AnyEvent::Log::COLLECT> context where all messages normally end up,
		493	from there to C<$AnyEvent::Log::FILTER> where log messages with lower
407	C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered away and then to the	494	priority then C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered out and then
408	AnyEvent::Log::Default context to be passed to C<warn>.	495	to the C<$AnyEvent::Log::LOG> context to be passed to C<warn>.
409		496
410	Splitting the top level context into three contexts makes it easy to set	497	This makes it easy to set a global logging level (by modifying $FILTER),
411	a global logging level (by modifying the root context), but still allow	498	but still allow other contexts to send, for example, their debug and trace
412	other contexts to log, for example, their debug and trace messages to the
413	default target despite the global logging level, or to attach additional	499	messages to the $LOG target despite the global logging level, or to attach
414	log targets that log messages, regardless of the global logging level.	500	additional log targets that log messages, regardless of the global logging
		501	level.
415		502
416	It also makes it easy to replace the default warn-logger by something that	503	It also makes it easy to modify the default warn-logger ($LOG) to
417	logs to a file, or to attach additional logging targets.	504	something that logs to a file, or to attach additional logging targets
		505	(such as loggign to a file) by attaching it to $FILTER.
418		506
419	=head2 CREATING/FINDING/DESTROYING CONTEXTS	507	=head2 CREATING/FINDING/DESTROYING CONTEXTS
420		508
421	=over 4	509	=over 4
422		510
…		…
454	This can be used to implement config-file (re-)loading: before loading a	542	This can be used to implement config-file (re-)loading: before loading a
455	configuration, reset all contexts.	543	configuration, reset all contexts.
456		544
457	=cut	545	=cut
458		546
		547	our $ORIG_VERBOSE = $AnyEvent::VERBOSE;
		548	$AnyEvent::VERBOSE = 9;
		549
459	sub reset {	550	sub reset {
460	# hard to kill complex data structures	551	# hard to kill complex data structures
461	# we recreate all package loggers and reset the hierarchy	552	# we "recreate" all package loggers and reset the hierarchy
462	while (my ($k, $v) = each %CTX) {	553	while (my ($k, $v) = each %CTX) {
463	@$v = ($k, (1 << 10) - 1 - 1, { });	554	@$v = ($k, (1 << 10) - 1 - 1, { });
464		555
465	my $pkg = $k =~ /^(.+)::/ ? $1 : "AE::Log::Top";	556	$v->attach ($k =~ /^(.+)::/ ? $CTX{$1} : $AnyEvent::Log::COLLECT);
466	$v->attach ($CTX{$pkg});
467	}	557	}
468		558
469	$AnyEvent::Log::Default->parents;	559	@$_ = ($_->[0], (1 << 10) - 1 - 1)
470	$AnyEvent::Log::Default->title ("AnyEvent::Log::Default");	560	for $LOG, $FILTER, $COLLECT;
471	$AnyEvent::Log::Default->log_cb (sub {
472	warn shift;
473	0
474	});
475	$CTX{"AnyEvent::Log::Default"} = $CTX{"AE::Log::Default"} = $AnyEvent::Log::Default;
476		561
477	$AnyEvent::Log::Root->parents ($AnyEvent::Log::Default);	562	#$LOG->slaves;
478	$AnyEvent::Log::Root->title ("AnyEvent::Log::Root");	563	$LOG->title ('$AnyEvent::Log::LOG');
479	$AnyEvent::Log::Root->level ($AnyEvent::VERBOSE);	564	$LOG->log_to_warn;
480	$CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $AnyEvent::Log::Root;
481		565
482	$AnyEvent::Log::Top->parents ($AnyEvent::Log::Root);	566	$FILTER->slaves ($LOG);
483	$AnyEvent::Log::Top->title ("AnyEvent::Log::Top");	567	$FILTER->title ('$AnyEvent::Log::FILTER');
484	$CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $AnyEvent::Log::Top;	568	$FILTER->level ($ORIG_VERBOSE);
		569
		570	$COLLECT->slaves ($FILTER);
		571	$COLLECT->title ('$AnyEvent::Log::COLLECT');
485		572
486	_reassess;	573	_reassess;
487	}	574	}
488		575
		576	# override AE::log/logger
		577	AnyEvent::log = AE::log = \&log;
		578	AnyEvent::logger = AE::logger = \&logger;
		579
		580	# convert AnyEvent loggers to AnyEvent::Log loggers
		581	$_->[0] = ctx $_->[0] # convert "pkg" to "ctx"
		582	for values %LOGGER;
		583
489	# create the default logger contexts	584	# create the default logger contexts
490	$AnyEvent::Log::Default = ctx undef;	585	$LOG = ctx undef;
491	$AnyEvent::Log::Root = ctx undef;	586	$FILTER = ctx undef;
492	$AnyEvent::Log::Top = ctx undef;	587	$COLLECT = ctx undef;
493		588
494	AnyEvent::Log::reset;	589	AnyEvent::Log::reset;
495		590
496	# hello, CPAN, please catch me	591	# hello, CPAN, please catch me
497	package AnyEvent::Log::Default;
498	package AE::Log::Default;
499	package AnyEvent::Log::Root;
500	package AE::Log::Root;
501	package AnyEvent::Log::Top;	592	package AnyEvent::Log::LOG;
502	package AE::Log::Top;	593	package AE::Log::LOG;
		594	package AnyEvent::Log::FILTER;
		595	package AE::Log::FILTER;
		596	package AnyEvent::Log::COLLECT;
		597	package AE::Log::COLLECT;
503		598
504	package AnyEvent::Log::Ctx;	599	package AnyEvent::Log::Ctx;
505		600
506	# 0 1 2 3 4	601	# 0 1 2 3 4
507	# [$title, $level, %$parents, &$logcb, &$fmtcb]	602	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
508		603
509	=item $ctx = new AnyEvent::Log::Ctx methodname => param...	604	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
510		605
511	This is a convenience constructor that makes it simpler to construct	606	This is a convenience constructor that makes it simpler to construct
512	anonymous logging contexts.	607	anonymous logging contexts.
…		…
515	name as the key with the value as parameter, unless the value is an	610	name as the key with the value as parameter, unless the value is an
516	arrayref, in which case it calls the method with the contents of the	611	arrayref, in which case it calls the method with the contents of the
517	array. The methods are called in the same order as specified.	612	array. The methods are called in the same order as specified.
518		613
519	Example: create a new logging context and set both the default logging	614	Example: create a new logging context and set both the default logging
520	level, some parent contexts and a logging callback.	615	level, some slave contexts and a logging callback.
521		616
522	$ctx = new AnyEvent::Log::Ctx	617	$ctx = new AnyEvent::Log::Ctx
523	title => "dubious messages",	618	title => "dubious messages",
524	level => "error",	619	level => "error",
525	log_cb => sub { print STDOUT shift; 0 },	620	log_cb => sub { print STDOUT shift; 0 },
526	parents => [$ctx1, $ctx, $ctx2],	621	slaves => [$ctx1, $ctx, $ctx2],
527	;	622	;
528		623
529	=back	624	=back
530		625
531	=cut	626	=cut
…		…
644	AnyEvent::Log::_reassess;	739	AnyEvent::Log::_reassess;
645	}	740	}
646		741
647	=back	742	=back
648		743
649	=head3 PARENT CONTEXTS	744	=head3 SLAVE CONTEXTS
650		745
651	The following methods attach and detach another logging context to a	746	The following methods attach and detach another logging context to a
652	logging context.	747	logging context.
653		748
654	Log messages are propagated to all parent contexts, unless the logging	749	Log messages are propagated to all slave contexts, unless the logging
655	callback consumes the message.	750	callback consumes the message.
656		751
657	=over 4	752	=over 4
658		753
659	=item $ctx->attach ($ctx2[, $ctx3...])	754	=item $ctx->attach ($ctx2[, $ctx3...])
660		755
661	Attaches the given contexts as parents to this context. It is not an error	756	Attaches the given contexts as slaves to this context. It is not an error
662	to add a context twice (the second add will be ignored).	757	to add a context twice (the second add will be ignored).
663		758
664	A context can be specified either as package name or as a context object.	759	A context can be specified either as package name or as a context object.
665		760
666	=item $ctx->detach ($ctx2[, $ctx3...])	761	=item $ctx->detach ($ctx2[, $ctx3...])
667		762
668	Removes the given parents from this context - it's not an error to attempt	763	Removes the given slaves from this context - it's not an error to attempt
669	to remove a context that hasn't been added.	764	to remove a context that hasn't been added.
670		765
671	A context can be specified either as package name or as a context object.	766	A context can be specified either as package name or as a context object.
672		767
673	=item $ctx->parents ($ctx2[, $ctx3...])	768	=item $ctx->slaves ($ctx2[, $ctx3...])
674		769
675	Replaces all parents attached to this context by the ones given.	770	Replaces all slaves attached to this context by the ones given.
676		771
677	=cut	772	=cut
678		773
679	sub attach {	774	sub attach {
680	my $ctx = shift;	775	my $ctx = shift;
…		…
688		783
689	delete $ctx->[2]{$_+0}	784	delete $ctx->[2]{$_+0}
690	for map { AnyEvent::Log::ctx $_ } @_;	785	for map { AnyEvent::Log::ctx $_ } @_;
691	}	786	}
692		787
693	sub parents {	788	sub slaves {
694	undef $_[0][2];	789	undef $_[0][2];
695	&attach;	790	&attach;
696	}	791	}
697		792
698	=back	793	=back
699		794
700	=head3 MESSAGE LOGGING	795	=head3 LOG TARGETS
701		796
702	The following methods configure how the logging context actually does	797	The following methods configure how the logging context actually does
703	the logging (which consists of formatting the message and printing it or	798	the logging (which consists of formatting the message and printing it or
704	whatever it wants to do with it) and also allows you to log messages	799	whatever it wants to do with it).
705	directly to a context, without going via your package context.
706		800
707	=over 4	801	=over 4
708		802
709	=item $ctx->log_cb ($cb->($str))	803	=item $ctx->log_cb ($cb->($str)
710		804
711	Replaces the logging callback on the context (C<undef> disables the	805	Replaces the logging callback on the context (C<undef> disables the
712	logging callback).	806	logging callback).
713		807
714	The logging callback is responsible for handling formatted log messages	808	The logging callback is responsible for handling formatted log messages
715	(see C<fmt_cb> below) - normally simple text strings that end with a	809	(see C<fmt_cb> below) - normally simple text strings that end with a
716	newline (and are possibly multiline themselves).	810	newline (and are possibly multiline themselves).
717		811
718	It also has to return true iff it has consumed the log message, and false	812	It also has to return true iff it has consumed the log message, and false
719	if it hasn't. Consuming a message means that it will not be sent to any	813	if it hasn't. Consuming a message means that it will not be sent to any
720	parent context. When in doubt, return C<0> from your logging callback.	814	slave context. When in doubt, return C<0> from your logging callback.
721		815
722	Example: a very simple logging callback, simply dump the message to STDOUT	816	Example: a very simple logging callback, simply dump the message to STDOUT
723	and do not consume it.	817	and do not consume it.
724		818
725	$ctx->log_cb (sub { print STDERR shift; 0 });	819	$ctx->log_cb (sub { print STDERR shift; 0 });
…		…
733	your program.	827	your program.
734		828
735	$ctx->levels ("debug", "trace");	829	$ctx->levels ("debug", "trace");
736	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages	830	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages
737		831
738	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	832	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $orig_ctx, $level, $message))
739		833
740	Replaces the formatting callback on the context (C<undef> restores the	834	Replaces the formatting callback on the context (C<undef> restores the
741	default formatter).	835	default formatter).
742		836
743	The callback is passed the (possibly fractional) timestamp, the original	837	The callback is passed the (possibly fractional) timestamp, the original
744	logging context, the (numeric) logging level and the raw message string and needs to	838	logging context, the (numeric) logging level and the raw message string
745	return a formatted log message. In most cases this will be a string, but	839	and needs to return a formatted log message. In most cases this will be a
746	it could just as well be an array reference that just stores the values.	840	string, but it could just as well be an array reference that just stores
		841	the values.
		842
		843	If, for some reason, you want to use C<caller> to find out more baout the
		844	logger then you should walk up the call stack until you are no longer
		845	inside the C<AnyEvent::Log> package.
747		846
748	Example: format just the raw message, with numeric log level in angle	847	Example: format just the raw message, with numeric log level in angle
749	brackets.	848	brackets.
750		849
751	$ctx->fmt_cb (sub {	850	$ctx->fmt_cb (sub {
…		…
768	"$msg->[3]";	867	"$msg->[3]";
769		868
770	0	869	0
771	});	870	});
772		871
		872	=item $ctx->log_to_warn
		873
		874	Sets the C<log_cb> to simply use C<CORE::warn> to report any messages
		875	(usually this logs to STDERR).
		876
		877	=item $ctx->log_to_file ($path)
		878
		879	Sets the C<log_cb> to log to a file (by appending), unbuffered.
		880
		881	=item $ctx->log_to_path ($path)
		882
		883	Same as C<< ->log_to_file >>, but opens the file for each message. This
		884	is much slower, but allows you to change/move/rename/delete the file at
		885	basically any time.
		886
		887	Needless(?) to say, if you do not want to be bitten by some evil person
		888	calling C<chdir>, the path should be absolute. Doesn't help with
		889	C<chroot>, but hey...
		890
		891	=item $ctx->log_to_syslog ([$facility])
		892
		893	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and
		894	all the others in the obvious way. If specified, then the C<$facility> is
		895	used as the facility (C<user>, C<auth>, C<local0> and so on). The default
		896	facility is C<user>.
		897
		898	Note that this function also sets a C<fmt_cb> - the logging part requires
		899	an array reference with [$level, $str] as input.
		900
773	=cut	901	=cut
774		902
775	sub log_cb {	903	sub log_cb {
776	my ($ctx, $cb) = @_;	904	my ($ctx, $cb) = @_;
777		905
…		…
782	my ($ctx, $cb) = @_;	910	my ($ctx, $cb) = @_;
783		911
784	$ctx->[4] = $cb;	912	$ctx->[4] = $cb;
785	}	913	}
786		914
787	=item $ctx->log ($level, $msg[, @params])	915	sub log_to_warn {
		916	my ($ctx, $path) = @_;
788		917
789	Same as C<AnyEvent::Log::log>, but uses the given context as log context.	918	$ctx->log_cb (sub {
		919	warn shift;
		920	0
		921	});
		922	}
790		923
791	=item $logger = $ctx->logger ($level[, \$enabled])	924	sub log_to_file {
792		925	my ($ctx, $path) = @_;
793	Same as C<AnyEvent::Log::logger>, but uses the given context as log
794	context.
795
796	=cut
797
798	*log = \&AnyEvent::Log::_log;
799	*logger = \&AnyEvent::Log::_logger;
800
801	1;
802
803	=back
804
805	=head1 EXAMPLES
806
807	This section shows some common configurations.
808
809	=over 4
810
811	=item Setting the global logging level.
812
813	Either put PERL_ANYEVENT_VERBOSE=<number> into your environment before
814	running your program, or modify the log level of the root context:
815
816	PERL_ANYEVENT_VERBOSE=5 ./myprog
817
818	$AnyEvent::Log::Root->level ("warn");
819
820	=item Append all messages to a file instead of sending them to STDERR.
821
822	This is affected by the global logging level.
823		926
824	open my $fh, ">>", $path	927	open my $fh, ">>", $path
825	or die "$path: $!";	928	or die "$path: $!";
826		929
827	$AnyEvent::Log::Default->log_cb (sub {	930	$ctx->log_cb (sub {
828	syswrite $fh, shift;	931	syswrite $fh, shift;
829	0	932	0
830	});	933	});
		934	}
		935
		936	sub log_to_path {
		937	my ($ctx, $path) = @_;
		938
		939	$ctx->log_cb (sub {
		940	open my $fh, ">>", $path
		941	or die "$path: $!";
		942
		943	syswrite $fh, shift;
		944	0
		945	});
		946	}
		947
		948	sub log_to_syslog {
		949	my ($ctx, $facility) = @_;
		950
		951	require Sys::Syslog;
		952
		953	$ctx->fmt_cb (sub {
		954	my $str = $_[3];
		955	$str =~ s/\n(?=.)/\n+ /g;
		956
		957	[$_[2], "($_[1][0]) $str"]
		958	});
		959
		960	$facility \|\|= "user";
		961
		962	$ctx->log_cb (sub {
		963	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;
		964
		965	Sys::Syslog::syslog ("$facility\|" . ($lvl - 1), $_)
		966	for split /\n/, $_[0][1];
		967
		968	0
		969	});
		970	}
		971
		972	=back
		973
		974	=head3 MESSAGE LOGGING
		975
		976	These methods allow you to log messages directly to a context, without
		977	going via your package context.
		978
		979	=over 4
		980
		981	=item $ctx->log ($level, $msg[, @params])
		982
		983	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
		984
		985	=item $logger = $ctx->logger ($level[, \$enabled])
		986
		987	Same as C<AnyEvent::Log::logger>, but uses the given context as log
		988	context.
		989
		990	=cut
		991
		992	*log = \&AnyEvent::Log::_log;
		993	*logger = \&AnyEvent::Log::_logger;
		994
		995	=back
		996
		997	=cut
		998
		999	package AnyEvent::Log;
		1000
		1001	=head1 CONFIGURATION VIA $ENV{PERL_ANYEVENT_LOG}
		1002
		1003	Logging can also be configured by setting the environment variable
		1004	C<PERL_ANYEVENT_LOG> (or C<AE_LOG>).
		1005
		1006	The value consists of one or more logging context specifications separated
		1007	by C<:> or whitespace. Each logging specification in turn starts with a
		1008	context name, followed by C<=>, followed by zero or more comma-separated
		1009	configuration directives, here are some examples:
		1010
		1011	# set default logging level
		1012	filter=warn
		1013
		1014	# log to file instead of to stderr
		1015	log=file=/tmp/mylog
		1016
		1017	# log to file in addition to stderr
		1018	log=+%file:%file=file=/tmp/mylog
		1019
		1020	# enable debug log messages, log warnings and above to syslog
		1021	filter=debug:log=+%warnings:%warnings=warn,syslog=LOG_LOCAL0
		1022
		1023	# log trace messages (only) from AnyEvent::Debug to file
		1024	AnyEvent::Debug=+%trace:%trace=only,trace,file=/tmp/tracelog
		1025
		1026	A context name in the log specification can be any of the following:
		1027
		1028	=over 4
		1029
		1030	=item C<collect>, C<filter>, C<log>
		1031
		1032	Correspond to the three predefined C<$AnyEvent::Log::COLLECT>,
		1033	C<AnyEvent::Log::FILTER> and C<$AnyEvent::Log::LOG> contexts.
		1034
		1035	=item C<%name>
		1036
		1037	Context names starting with a C<%> are anonymous contexts created when the
		1038	name is first mentioned. The difference to package contexts is that by
		1039	default they have no attached slaves.
		1040
		1041	=item a perl package name
		1042
		1043	Any other string references the logging context associated with the given
		1044	Perl C<package>. In the unlikely case where you want to specify a package
		1045	context that matches on of the other context name forms, you can add a
		1046	C<::> to the package name to force interpretation as a package.
		1047
		1048	=back
		1049
		1050	The configuration specifications can be any number of the following:
		1051
		1052	=over 4
		1053
		1054	=item C<stderr>
		1055
		1056	Configures the context to use Perl's C<warn> function (which typically
		1057	logs to C<STDERR>). Works like C<log_to_warn>.
		1058
		1059	=item C<file=>I<path>
		1060
		1061	Configures the context to log to a file with the given path. Works like
		1062	C<log_to_file>.
		1063
		1064	=item C<path=>I<path>
		1065
		1066	Configures the context to log to a file with the given path. Works like
		1067	C<log_to_path>.
		1068
		1069	=item C<syslog> or C<syslog=>I<expr>
		1070
		1071	Configures the context to log to syslog. If I<expr> is given, then it is
		1072	evaluated in the L<Sys::Syslog> package, so you could use:
		1073
		1074	log=syslog=LOG_LOCAL0
		1075
		1076	=item C<nolog>
		1077
		1078	Configures the context to not log anything by itself, which is the
		1079	default. Same as C<< $ctx->log_cb (undef) >>.
		1080
		1081	=item C<0> or C<off>
		1082
		1083	Sets the logging level of the context ot C<0>, i.e. all messages will be
		1084	filtered out.
		1085
		1086	=item C<all>
		1087
		1088	Enables all logging levels, i.e. filtering will effectively be switched
		1089	off (the default).
		1090
		1091	=item C<only>
		1092
		1093	Disables all logging levels, and changes the interpretation of following
		1094	level specifications to enable the specified level only.
		1095
		1096	Example: only enable debug messages for a context.
		1097
		1098	context=only,debug
		1099
		1100	=item C<except>
		1101
		1102	Enables all logging levels, and changes the interpretation of following
		1103	level specifications to disable that level. Rarely used.
		1104
		1105	Example: enable all logging levels except fatal and trace (this is rather
		1106	nonsensical).
		1107
		1108	filter=exept,fatal,trace
		1109
		1110	=item C<level>
		1111
		1112	Enables all logging levels, and changes the interpretation of following
		1113	level specifications to be "that level or any higher priority
		1114	message". This is the default.
		1115
		1116	Example: log anything at or above warn level.
		1117
		1118	filter=warn
		1119
		1120	# or, more verbose
		1121	filter=only,level,warn
		1122
		1123	=item C<1>..C<9> or a logging level name (C<error>, C<debug> etc.)
		1124
		1125	A numeric loglevel or the name of a loglevel will be interpreted according
		1126	to the most recent C<only>, C<except> or C<level> directive. By default,
		1127	specifying a logging level enables that and any higher priority messages.
		1128
		1129	=item C<+>I<context>
		1130
		1131	Attaches the named context as slave to the context.
		1132
		1133	=item C<+>
		1134
		1135	A line C<+> detaches all contexts, i.e. clears the slave list from the
		1136	context. Anonymous (C<%name>) contexts have no attached slaves by default,
		1137	but package contexts have the parent context as slave by default.
		1138
		1139	Example: log messages from My::Module to a file, do not send them to the
		1140	default log collector.
		1141
		1142	My::Module=+,file=/tmp/mymodulelog
		1143
		1144	=back
		1145
		1146	Any character can be escaped by prefixing it with a C<\> (backslash), as
		1147	usual, so to log to a file containing a comma, colon, backslash and some
		1148	spaces in the filename, you would do this:
		1149
		1150	PERL_ANYEVENT_LOG='log=file=/some\ \:file\ with\,\ \\-escapes'
		1151
		1152	Since whitespace (which includes newlines) is allowed, it is fine to
		1153	specify multiple lines in C<PERL_ANYEVENT_LOG>, e.g.:
		1154
		1155	PERL_ANYEVENT_LOG="
		1156	filter=warn
		1157	AnyEvent::Debug=+%trace
		1158	%trace=only,trace,+log
		1159	" myprog
		1160
		1161	Also, in the unlikely case when you want to concatenate specifications,
		1162	use whitespace as separator, as C<::> will be interpreted as part of a
		1163	module name, an empty spec with two separators:
		1164
		1165	PERL_ANYEVENT_LOG="$PERL_ANYEVENT_LOG MyMod=debug"
		1166
		1167	=cut
		1168
		1169	for (my $spec = $ENV{PERL_ANYEVENT_LOG}) {
		1170	my %anon;
		1171
		1172	my $pkg = sub {
		1173	$_[0] eq "log" ? $LOG
		1174	: $_[0] eq "filter" ? $FILTER
		1175	: $_[0] eq "collect" ? $COLLECT
		1176	: $_[0] =~ /^%(.+)$/ ? ($anon{$1} \|\|= ctx undef)
		1177	: $_[0] =~ /^(.*?)(?:::)?$/ ? ctx "$1" # egad :/
		1178	: die # never reached?
		1179	};
		1180
		1181	/\G[[:space:]]+/gc; # skip initial whitespace
		1182
		1183	while (/\G((?:[^:=[:space:]]+\|::\|\\.)+)=/gc) {
		1184	my $ctx = $pkg->($1);
		1185	my $level = "level";
		1186
		1187	while (/\G((?:[^,:[:space:]]+\|::\|\\.)+)/gc) {
		1188	for ("$1") {
		1189	if ($_ eq "stderr" ) { $ctx->log_to_warn;
		1190	} elsif (/^file=(.+)/ ) { $ctx->log_to_file ("$1");
		1191	} elsif (/^path=(.+)/ ) { $ctx->log_to_path ("$1");
		1192	} elsif (/syslog(?:=(.*))?/ ) { require Sys::Syslog; $ctx->log_to_syslog ($1);
		1193	} elsif ($_ eq "nolog" ) { $ctx->log_cb (undef);
		1194	} elsif (/^\+(.+)$/ ) { $ctx->attach ($pkg->("$1"));
		1195	} elsif ($_ eq "+" ) { $ctx->slaves;
		1196	} elsif ($_ eq "off" or $_ eq "0") { $ctx->level (0);
		1197	} elsif ($_ eq "all" ) { $ctx->level ("all");
		1198	} elsif ($_ eq "level" ) { $ctx->level ("all"); $level = "level";
		1199	} elsif ($_ eq "only" ) { $ctx->level ("off"); $level = "enable";
		1200	} elsif ($_ eq "except" ) { $ctx->level ("all"); $level = "disable";
		1201	} elsif (/^\d$/ ) { $ctx->$level ($_);
		1202	} elsif (exists $STR2LEVEL{$_} ) { $ctx->$level ($_);
		1203	} else { die "PERL_ANYEVENT_LOG ($spec): parse error at '$_'\n";
		1204	}
		1205	}
		1206
		1207	/\G,/gc or last;
		1208	}
		1209
		1210	/\G[:[:space:]]+/gc or last;
		1211	}
		1212
		1213	/\G[[:space:]]+/gc; # skip trailing whitespace
		1214
		1215	if (/\G(.+)/g) {
		1216	die "PERL_ANYEVENT_LOG ($spec): parse error at '$1'\n";
		1217	}
		1218	}
		1219
		1220	1;
		1221
		1222	=head1 EXAMPLES
		1223
		1224	This section shows some common configurations, both as code, and as
		1225	C<PERL_ANYEVENT_LOG> string.
		1226
		1227	=over 4
		1228
		1229	=item Setting the global logging level.
		1230
		1231	Either put C<PERL_ANYEVENT_VERBOSE=><number> into your environment before
		1232	running your program, use C<PERL_ANYEVENT_LOG> or modify the log level of
		1233	the root context at runtime:
		1234
		1235	PERL_ANYEVENT_VERBOSE=5 ./myprog
		1236
		1237	PERL_ANYEVENT_LOG=log=warn
		1238
		1239	$AnyEvent::Log::FILTER->level ("warn");
		1240
		1241	=item Append all messages to a file instead of sending them to STDERR.
		1242
		1243	This is affected by the global logging level.
		1244
		1245	$AnyEvent::Log::LOG->log_to_file ($path);
		1246
		1247	PERL_ANYEVENT_LOG=log=file=/some/path
831		1248
832	=item Write all messages with priority C<error> and higher to a file.	1249	=item Write all messages with priority C<error> and higher to a file.
833		1250
834	This writes them only when the global logging level allows it, because	1251	This writes them only when the global logging level allows it, because
835	it is attached to the default context which is invoked I<after> global	1252	it is attached to the default context which is invoked I<after> global
836	filtering.	1253	filtering.
837		1254
838	open my $fh, ">>", $path	1255	$AnyEvent::Log::FILTER->attach (
839	or die "$path: $!";	1256	new AnyEvent::Log::Ctx log_to_file => $path);
840		1257
841	$AnyEvent::Log::Default->attach (new AnyEvent::Log::Ctx	1258	PERL_ANYEVENT_LOG=filter=+%filelogger:%filelogger=file=/some/path
842	log_cb => sub { syswrite $fh, shift; 0 });
843		1259
844	This writes them regardless of the global logging level, because it is	1260	This writes them regardless of the global logging level, because it is
845	attached to the toplevel context, which receives all messages I<before>	1261	attached to the toplevel context, which receives all messages I<before>
846	the global filtering.	1262	the global filtering.
847		1263
848	$AnyEvent::Log::Top->attach (new AnyEvent::Log::Ctx	1264	$AnyEvent::Log::COLLECT->attach (
849	log_cb => sub { syswrite $fh, shift; 0 });	1265	new AnyEvent::Log::Ctx log_to_file => $path);
850		1266
		1267	PERL_ANYEVENT_LOG=%filelogger=file=/some/path:collect=+%filelogger
		1268
851	In both cases, messages are still written to STDOUT.	1269	In both cases, messages are still written to STDERR.
852		1270
853	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).	1271	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
854		1272
855	Attach the CyAnyEvent::Log::Default> context to the C<AnyEvent::Debug>	1273	Attach the C<$AnyEvent::Log::LOG> context to the C<AnyEvent::Debug>
856	context and increase the C<AnyEvent::Debug> logging level - this simply
857	circumvents the global filtering for trace messages.	1274	context - this simply circumvents the global filtering for trace messages.
858		1275
859	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;	1276	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
860	$debug->attach ($AnyEvent::Log::Default);	1277	$debug->attach ($AnyEvent::Log::LOG);
861	$debug->levels ("trace"); # not "level"!
862		1278
863	This of course works for any package.	1279	PERL_ANYEVENT_LOG=AnyEvent::Debug=+log
		1280
		1281	This of course works for any package, not just L<AnyEvent::Debug>, but
		1282	assumes the log level for AnyEvent::Debug hasn't been changed from the
		1283	default.
864		1284
865	=back	1285	=back
866		1286
867	=head1 AUTHOR	1287	=head1 AUTHOR
868		1288
869	Marc Lehmann <schmorp@schmorp.de>	1289	Marc Lehmann <schmorp@schmorp.de>
870	http://home.schmorp.de/	1290	http://home.schmorp.de/
871		1291
872	=cut	1292	=cut
		1293

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents): Revision 1.17 by root, Sat Aug 20 02:21:53 2011 UTC vs. Revision 1.43 by root, Mon Sep 5 07:21:54 2011 UTC

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.17 by root, Sat Aug 20 02:21:53 2011 UTC vs.
Revision 1.43 by root, Mon Sep 5 07:21:54 2011 UTC