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

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.8 by root, Fri Aug 19 19:20:36 2011 UTC vs.
Revision 1.37 by root, Thu Aug 25 06:34:11 2011 UTC

…		…
2		2
3	AnyEvent::Log - simple logging "framework"	3	AnyEvent::Log - simple logging "framework"
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	# simple use	7	Simple uses:
		8
8	use AnyEvent;	9	use AnyEvent;
9		10
10	AE::log debug => "hit my knee";	11	AE::log debug => "hit my knee";
11	AE::log warn => "it's a bit too hot";	12	AE::log warn => "it's a bit too hot";
12	AE::log error => "the flag was false!";	13	AE::log error => "the flag was false!";
13	AE::log fatal => "the bit toggled! run!";	14	AE::log fatal => "the bit toggled! run!"; # never returns
14		15
15	# complex use	16	"Complex" uses (for speed sensitive code):
		17
16	use AnyEvent::Log;	18	use AnyEvent::Log;
17		19
18	my $tracer = AnyEvent::Log::logger trace => \$my $trace;	20	my $tracer = AnyEvent::Log::logger trace => \$my $trace;
19		21
20	$tracer->("i am here") if $trace;	22	$tracer->("i am here") if $trace;
21	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;	23	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;
22		24
23	#TODO: config	25	Configuration (also look at the EXAMPLES section):
24	#TODO: ctx () becomes caller[0]...	26
		27	# set logging for the current package to errors and higher only
		28	AnyEvent::Log::ctx->level ("error");
		29
		30	# set logging level to suppress anything below "notice"
		31	$AnyEvent::Log::FILTER->level ("notice");
		32
		33	# send all critical and higher priority messages to syslog,
		34	# regardless of (most) other settings
		35	$AnyEvent::Log::COLLECT->attach (new AnyEvent::Log::Ctx
		36	level => "critical",
		37	log_to_syslog => 0,
		38	);
25		39
26	=head1 DESCRIPTION	40	=head1 DESCRIPTION
27		41
28	This module implements a relatively simple "logging framework". It doesn't	42	This module implements a relatively simple "logging framework". It doesn't
29	attempt to be "the" logging solution or even "a" logging solution for	43	attempt to be "the" logging solution or even "a" logging solution for
30	AnyEvent - AnyEvent simply creates logging messages internally, and this	44	AnyEvent - AnyEvent simply creates logging messages internally, and this
31	module more or less exposes the mechanism, with some extra spiff to allow	45	module more or less exposes the mechanism, with some extra spiff to allow
32	using it from other modules as well.	46	using it from other modules as well.
33		47
34	Remember that the default verbosity level is C<0>, so nothing will be	48	Remember that the default verbosity level is C<0> (C<off>), so nothing
35	logged, ever, unless you set C<PERL_ANYEVENT_VERBOSE> to a higher number	49	will be logged, unless you set C<PERL_ANYEVENT_VERBOSE> to a higher number
36	before starting your program.#TODO	50	before starting your program, or change the logging level at runtime with
		51	something like:
37		52
38	Possible future extensions are to allow custom log targets (where the	53	use AnyEvent::Log;
39	level is an object), log filtering based on package, formatting, aliasing	54	$AnyEvent::Log::FILTER->level ("info");
40	or package groups.
41		55
		56	The design goal behind this module was to keep it simple (and small),
		57	but make it powerful enough to be potentially useful for any module, and
		58	extensive enough for the most common tasks, such as logging to multiple
		59	targets, or being able to log into a database.
		60
		61	The module is also usable before AnyEvent itself is initialised, in which
		62	case some of the functionality might be reduced.
		63
		64	The amount of documentation might indicate otherwise, but the runtime part
		65	of the module is still just below 300 lines of code.
		66
		67	=head1 LOGGING LEVELS
		68
		69	Logging levels in this module range from C<1> (highest priority) to C<9>
		70	(lowest priority). Note that the lowest numerical value is the highest
		71	priority, so when this document says "higher priority" it means "lower
		72	numerical value".
		73
		74	Instead of specifying levels by name you can also specify them by aliases:
		75
		76	LVL NAME SYSLOG PERL NOTE
		77	1 fatal emerg exit aborts program!
		78	2 alert
		79	3 critical crit
		80	4 error err die
		81	5 warn warning
		82	6 note notice
		83	7 info
		84	8 debug
		85	9 trace
		86
		87	As you can see, some logging levels have multiple aliases - the first one
		88	is the "official" name, the second one the "syslog" name (if it differs)
		89	and the third one the "perl" name, suggesting that you log C<die> messages
		90	at C<error> priority.
		91
		92	You can normally only log a single message at highest priority level
		93	(C<1>, C<fatal>), because logging a fatal message will also quit the
		94	program - so use it sparingly :)
		95
		96	Some methods also offer some extra levels, such as C<0>, C<off>, C<none>
		97	or C<all> - these are only valid in the methods they are documented for.
		98
42	=head1 LOG FUNCTIONS	99	=head1 LOGGING FUNCTIONS
43		100
44	These functions allow you to log messages. They always use the caller's	101	These functions allow you to log messages. They always use the caller's
45	package as a "logging module/source". Also, the main logging function is	102	package as a "logging context". Also, the main logging function C<log> is
46	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is	103	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is
47	loaded.	104	loaded.
48		105
49	=over 4	106	=over 4
50		107
…		…
54		111
55	use Carp ();	112	use Carp ();
56	use POSIX ();	113	use POSIX ();
57		114
58	use AnyEvent (); BEGIN { AnyEvent::common_sense }	115	use AnyEvent (); BEGIN { AnyEvent::common_sense }
59	use AnyEvent::Util ();	116	#use AnyEvent::Util (); need to load this in a delayed fashion, as it uses AE::log
		117
		118	our $VERSION = $AnyEvent::VERSION;
		119
		120	our ($COLLECT, $FILTER, $LOG);
60		121
61	our ($now_int, $now_str1, $now_str2);	122	our ($now_int, $now_str1, $now_str2);
62		123
63	# Format Time, not public - yet?	124	# Format Time, not public - yet?
64	sub ft($) {	125	sub ft($) {
…		…
69	if $now_int != $i;	130	if $now_int != $i;
70		131
71	"$now_str1$f$now_str2"	132	"$now_str1$f$now_str2"
72	}	133	}
73		134
74	our %CTX; # all logging contexts	135	our %CTX; # all package contexts
75
76	my $default_log_cb = sub { 0 };
77		136
78	# creates a default package context object for the given package	137	# creates a default package context object for the given package
79	sub _pkg_ctx($) {	138	sub _pkg_ctx($) {
80	my $ctx = bless [$_[0], 0, {}, $default_log_cb], "AnyEvent::Log::Ctx";	139	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";
81		140
82	# link "parent" package	141	# link "parent" package
83	my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "";	142	my $parent = $_[0] =~ /^(.+)::/
		143	? $CTX{$1} \|\|= &_pkg_ctx ("$1")
		144	: $COLLECT;
84		145
85	$pkg = $CTX{$pkg} \|\|= &_pkg_ctx ($pkg);
86	$ctx->[2]{$pkg+0} = $pkg;	146	$ctx->[2]{$parent+0} = $parent;
87		147
88	$ctx	148	$ctx
89	}	149	}
90		150
91	=item AnyEvent::Log::log $level, $msg[, @args]	151	=item AnyEvent::Log::log $level, $msg[, @args]
92		152
93	Requests logging of the given C<$msg> with the given log level (1..9).	153	Requests logging of the given C<$msg> with the given log level, and
94	You can also use the following strings as log level: C<fatal> (1),	154	returns true if the message was logged I<somewhere>.
95	C<alert> (2), C<critical> (3), C<error> (4), C<warn> (5), C<note> (6),
96	C<info> (7), C<debug> (8), C<trace> (9).
97		155
98	For C<fatal> log levels, the program will abort.	156	For C<fatal> log levels, the program will abort.
99		157
100	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the	158	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the
101	C<$msg> is interpreted as an sprintf format string.	159	C<$msg> is interpreted as an sprintf format string.
…		…
107	supposed to return the message. It will be called only then the message	165	supposed to return the message. It will be called only then the message
108	actually gets logged, which is useful if it is costly to create the	166	actually gets logged, which is useful if it is costly to create the
109	message in the first place.	167	message in the first place.
110		168
111	Whether the given message will be logged depends on the maximum log level	169	Whether the given message will be logged depends on the maximum log level
112	and the caller's package.	170	and the caller's package. The return value can be used to ensure that
		171	messages or not "lost" - for example, when L<AnyEvent::Debug> detects a
		172	runtime error it tries to log it at C<die> level, but if that message is
		173	lost it simply uses warn.
113		174
114	Note that you can (and should) call this function as C<AnyEvent::log> or	175	Note that you can (and should) call this function as C<AnyEvent::log> or
115	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't	176	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't
116	need any additional functionality), as those functions will load the	177	need any additional functionality), as those functions will load the
117	logging module on demand only. They are also much shorter to write.	178	logging module on demand only. They are also much shorter to write.
118		179
119	Also, if you otpionally generate a lot of debug messages (such as when	180	Also, if you optionally generate a lot of debug messages (such as when
120	tracing some code), you should look into using a logger callback and a	181	tracing some code), you should look into using a logger callback and a
121	boolean enabler (see C<logger>, below).	182	boolean enabler (see C<logger>, below).
122		183
123	Example: log something at error level.	184	Example: log something at error level.
124		185
…		…
134		195
135	=cut	196	=cut
136		197
137	# also allow syslog equivalent names	198	# also allow syslog equivalent names
138	our %STR2LEVEL = (	199	our %STR2LEVEL = (
139	fatal => 1, emerg => 1,	200	fatal => 1, emerg => 1, exit => 1,
140	alert => 2,	201	alert => 2,
141	critical => 3, crit => 3,	202	critical => 3, crit => 3,
142	error => 4, err => 4,	203	error => 4, err => 4, die => 4,
143	warn => 5, warning => 5,	204	warn => 5, warning => 5,
144	note => 6, notice => 6,	205	note => 6, notice => 6,
145	info => 7,	206	info => 7,
146	debug => 8,	207	debug => 8,
147	trace => 9,	208	trace => 9,
148	);	209	);
149		210
150	sub now () { time }	211	sub now () { time }
		212
151	AnyEvent::post_detect {	213	AnyEvent::post_detect {
152	*now = \&AE::now;	214	*now = \&AE::now;
153	};	215	};
154		216
155	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);	217	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);
156		218
157	# time, ctx, level, msg	219	# time, ctx, level, msg
158	sub _format($$$$) {	220	sub _format($$$$) {
159	my $pfx = ft $_[0];	221	my $ts = ft $_[0];
		222	my $ct = " ";
160		223
161	join "",	224	my @res;
162	map "$pfx $_\n",	225
163	split /\n/,
164	sprintf "%-5s %s: %s", $LEVEL2STR[$_[2]], $_[1][0], $_[3]	226	for (split /\n/, sprintf "%-5s %s: %s", $LEVEL2STR[$_[2]], $_[1][0], $_[3]) {
		227	push @res, "$ts$ct$_\n";
		228	$ct = " + ";
		229	}
		230
		231	join "", @res
165	}	232	}
166		233
167	sub _log {	234	sub _log {
168	my ($ctx, $level, $format, @args) = @_;	235	my ($ctx, $level, $format, @args) = @_;
169		236
		237	$level = $level > 0 && $level <= 9
		238	? $level+0
170	$level = $level > 0 && $level <= 9 ? $level+0 : $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";	239	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";
171		240
172	my $mask = 1 << $level;	241	my $mask = 1 << $level;
173	my $now = AE::now;
174		242
175	my (@ctx, $did_format, $fmt);	243	my ($success, %seen, @ctx, $now, $fmt);
176		244
177	do {	245	do
178	if ($ctx->[1] & $mask) {	246	{
		247	# skip if masked
		248	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {
		249	if ($ctx->[3]) {
179	# logging target found	250	# logging target found
180		251
181	# get raw message	252	# now get raw message, unless we have it already
182	unless ($did_format) {	253	unless ($now) {
183	$format = $format->() if ref $format;	254	$format = $format->() if ref $format;
184	$format = sprintf $format, @args if @args;	255	$format = sprintf $format, @args if @args;
185	$format =~ s/\n$//;	256	$format =~ s/\n$//;
186	$did_format = 1;	257	$now = now;
		258	};
		259
		260	# format msg
		261	my $str = $ctx->[4]
		262	? $ctx->[4]($now, $_[0], $level, $format)
		263	: ($fmt \|\|= _format $now, $_[0], $level, $format);
		264
		265	$success = 1;
		266
		267	$ctx->[3]($str)
		268	or push @ctx, values %{ $ctx->[2] }; # not consumed - propagate
		269	} else {
		270	push @ctx, values %{ $ctx->[2] }; # not masked - propagate
		271	}
187	};	272	}
188
189	# format msg
190	my $str = $ctx->[4]
191	? $ctx->[4]($now, $_[0], $level, $format)
192	: $fmt \|\|= _format $now, $_[0], $level, $format;
193
194	$ctx->[3]($str)
195	and next;
196	}	273	}
197
198	# not consume - push parent contexts
199	push @ctx, values %{ $ctx->[2] };
200	} while $ctx = pop @ctx;	274	while $ctx = pop @ctx;
201		275
202	exit 1 if $level <= 1;	276	exit 1 if $level <= 1;
		277
		278	$success
203	}	279	}
204		280
205	sub log($$;@) {	281	sub log($$;@) {
206	_log	282	_log
207	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	283	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
…		…
211	AnyEvent::log = AE::log = \&log;	287	AnyEvent::log = AE::log = \&log;
212		288
213	=item $logger = AnyEvent::Log::logger $level[, \$enabled]	289	=item $logger = AnyEvent::Log::logger $level[, \$enabled]
214		290
215	Creates a code reference that, when called, acts as if the	291	Creates a code reference that, when called, acts as if the
216	C<AnyEvent::Log::log> function was called at this point with the givne	292	C<AnyEvent::Log::log> function was called at this point with the given
217	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with	293	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with
218	the C<AnyEvent::Log::log> function:	294	the C<AnyEvent::Log::log> function:
219		295
220	my $debug_log = AnyEvent::Log::logger "debug";	296	my $debug_log = AnyEvent::Log::logger "debug";
221		297
…		…
246	# and later in your program	322	# and later in your program
247	$debug_log->("yo, stuff here") if $debug;	323	$debug_log->("yo, stuff here") if $debug;
248		324
249	$debug and $debug_log->("123");	325	$debug and $debug_log->("123");
250		326
251	Note: currently the enabled var is always true - that will be fixed in a
252	future version :)
253
254	=cut	327	=cut
255		328
256	our %LOGGER;	329	our %LOGGER;
257		330
258	# re-assess logging status for all loggers	331	# re-assess logging status for all loggers
259	sub _reassess {	332	sub _reassess {
		333	local $SIG{__DIE__};
		334	my $die = sub { die };
		335
260	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {	336	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {
261	my ($ctx, $level, $renabled) = @$_;	337	my ($ctx, $level, $renabled) = @$_;
262		338
263	# to detetc whether a message would be logged, we # actually	339	# to detect whether a message would be logged, we actually
264	# try to log one and die. this isn't # fast, but we can be	340	# try to log one and die. this isn't fast, but we can be
265	# sure that the logging decision is correct :)	341	# sure that the logging decision is correct :)
266		342
267	$$renabled = !eval {	343	$$renabled = !eval {
268	local $SIG{__DIE__};
269
270	_log $ctx, $level, sub { die };	344	_log $ctx, $level, $die;
271		345
272	1	346	1
273	};	347	};
274
275	$$renabled = 1; # TODO
276	}	348	}
277	}	349	}
278		350
279	sub _logger($;$) {	351	sub _logger {
280	my ($ctx, $level, $renabled) = @_;	352	my ($ctx, $level, $renabled) = @_;
281		353
282	$renabled \|\|= \my $enabled;
283
284	$$renabled = 1;	354	$$renabled = 1;
285		355
286	my $logger = [$ctx, $level, $renabled];	356	my $logger = [$ctx, $level, $renabled];
287		357
288	$LOGGER{$logger+0} = $logger;	358	$LOGGER{$logger+0} = $logger;
289		359
290	_reassess $logger+0;	360	_reassess $logger+0;
291		361
		362	require AnyEvent::Util;
292	my $guard = AnyEvent::Util::guard {	363	my $guard = AnyEvent::Util::guard (sub {
293	# "clean up"	364	# "clean up"
294	delete $LOGGER{$logger+0};	365	delete $LOGGER{$logger+0};
295	};	366	});
296		367
297	sub {	368	sub {
298	$guard if 0; # keep guard alive, but don't cause runtime overhead	369	$guard if 0; # keep guard alive, but don't cause runtime overhead
299		370
300	_log $ctx, $level, @_	371	_log $ctx, $level, @_
…		…
306	_logger	377	_logger
307	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	378	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
308	@_	379	@_
309	}	380	}
310		381
311	#TODO
312
313	=back	382	=back
314		383
315	=head1 CONFIGURATION FUNCTIONALITY	384	=head1 LOGGING CONTEXTS
316		385
317	None, yet, except for C<PERL_ANYEVENT_VERBOSE>, described in the L<AnyEvent> manpage.	386	This module associates every log message with a so-called I<logging
		387	context>, based on the package of the caller. Every perl package has its
		388	own logging context.
318		389
319	#TODO: wahst a context	390	A logging context has three major responsibilities: filtering, logging and
320	#TODO	391	propagating the message.
		392
		393	For the first purpose, filtering, each context has a set of logging
		394	levels, called the log level mask. Messages not in the set will be ignored
		395	by this context (masked).
		396
		397	For logging, the context stores a formatting callback (which takes the
		398	timestamp, context, level and string message and formats it in the way
		399	it should be logged) and a logging callback (which is responsible for
		400	actually logging the formatted message and telling C<AnyEvent::Log>
		401	whether it has consumed the message, or whether it should be propagated).
		402
		403	For propagation, a context can have any number of attached I<slave
		404	contexts>. Any message that is neither masked by the logging mask nor
		405	masked by the logging callback returning true will be passed to all slave
		406	contexts.
		407
		408	Each call to a logging function will log the message at most once per
		409	context, so it does not matter (much) if there are cycles or if the
		410	message can arrive at the same context via multiple paths.
		411
		412	=head2 DEFAULTS
		413
		414	By default, all logging contexts have an full set of log levels ("all"), a
		415	disabled logging callback and the default formatting callback.
		416
		417	Package contexts have the package name as logging title by default.
		418
		419	They have exactly one slave - the context of the "parent" package. The
		420	parent package is simply defined to be the package name without the last
		421	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
		422	and C<AnyEvent> becomes ... C<$AnyEvent::Log::COLLECT> which is the
		423	exception of the rule - just like the "parent" of any single-component
		424	package name in Perl is C<main>, the default slave of any top-level
		425	package context is C<$AnyEvent::Log::COLLECT>.
		426
		427	Since perl packages form only an approximate hierarchy, this slave
		428	context can of course be removed.
		429
		430	All other (anonymous) contexts have no slaves and an empty title by
		431	default.
		432
		433	When the module is loaded it creates the C<$AnyEvent::Log::LOG> logging
		434	context that simply logs everything via C<warn>, without propagating
		435	anything anywhere by default. The purpose of this context is to provide
		436	a convenient place to override the global logging target or to attach
		437	additional log targets. It's not meant for filtering.
		438
		439	It then creates the C<$AnyEvent::Log::FILTER> context whose
		440	purpose is to suppress all messages with priority higher
		441	than C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the
		442	C<$AnyEvent::Log::LOG> context to it. The purpose of the filter context
		443	is to simply provide filtering according to some global log level.
		444
		445	Finally it creates the top-level package context C<$AnyEvent::Log::COLLECT>
		446	and attaches the C<$AnyEvent::Log::FILTER> context to it, but otherwise
		447	leaves it at default config. Its purpose is simply to collect all log
		448	messages system-wide.
		449
		450	The hierarchy is then:
		451
		452	any package, eventually -> $COLLECT -> $FILTER -> $LOG
		453
		454	The effect of all this is that log messages, by default, wander up to the
		455	C<$AnyEvent::Log::COLLECT> context where all messages normally end up,
		456	from there to C<$AnyEvent::Log::FILTER> where log messages with lower
		457	priority then C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered out and then
		458	to the C<$AnyEvent::Log::LOG> context to be passed to C<warn>.
		459
		460	This makes it easy to set a global logging level (by modifying $FILTER),
		461	but still allow other contexts to send, for example, their debug and trace
		462	messages to the $LOG target despite the global logging level, or to attach
		463	additional log targets that log messages, regardless of the global logging
		464	level.
		465
		466	It also makes it easy to modify the default warn-logger ($LOG) to
		467	something that logs to a file, or to attach additional logging targets
		468	(such as loggign to a file) by attaching it to $FILTER.
		469
		470	=head2 CREATING/FINDING/DESTROYING CONTEXTS
321		471
322	=over 4	472	=over 4
323		473
324	=item $ctx = AnyEvent::Log::ctx [$pkg]	474	=item $ctx = AnyEvent::Log::ctx [$pkg]
325		475
326	Returns a I<config> object for the given package name.	476	This function creates or returns a logging context (which is an object).
327		477
328	If no package name is given, returns the context for the current perl	478	If a package name is given, then the context for that packlage is
		479	returned. If it is called without any arguments, then the context for the
329	package (i.e. the same context as a C<AE::log> call would use).	480	callers package is returned (i.e. the same context as a C<AE::log> call
		481	would use).
330		482
331	If C<undef> is given, then it creates a new anonymous context that is not	483	If C<undef> is given, then it creates a new anonymous context that is not
332	tied to any package and is destroyed when no longer referenced.	484	tied to any package and is destroyed when no longer referenced.
333		485
334	=cut	486	=cut
…		…
338		490
339	ref $pkg	491	ref $pkg
340	? $pkg	492	? $pkg
341	: defined $pkg	493	: defined $pkg
342	? $CTX{$pkg} \|\|= AnyEvent::Log::_pkg_ctx $pkg	494	? $CTX{$pkg} \|\|= AnyEvent::Log::_pkg_ctx $pkg
343	: bless [undef, 0, undef, $default_log_cb], "AnyEvent::Log::Ctx"	495	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"
344	}	496	}
345		497
346	# create default root context	498	=item AnyEvent::Log::reset
347	{	499
348	my $root = ctx undef;	500	Resets all package contexts and recreates the default hierarchy if
349	$root->[0] = "";	501	necessary, i.e. resets the logging subsystem to defaults, as much as
350	$root->title ("default");	502	possible. This process keeps references to contexts held by other parts of
		503	the program intact.
		504
		505	This can be used to implement config-file (re-)loading: before loading a
		506	configuration, reset all contexts.
		507
		508	=cut
		509
		510	sub reset {
		511	# hard to kill complex data structures
		512	# we "recreate" all package loggers and reset the hierarchy
		513	while (my ($k, $v) = each %CTX) {
		514	@$v = ($k, (1 << 10) - 1 - 1, { });
		515
		516	$v->attach ($k =~ /^(.+)::/ ? $CTX{$1} : $AnyEvent::Log::COLLECT);
		517	}
		518
		519	@$_ = ($_->[0], (1 << 10) - 1 - 1)
		520	for $LOG, $FILTER, $COLLECT;
		521
		522	#$LOG->slaves;
		523	$LOG->title ('$AnyEvent::Log::LOG');
		524	$LOG->log_to_warn;
		525
		526	$FILTER->slaves ($LOG);
		527	$FILTER->title ('$AnyEvent::Log::FILTER');
351	$root->level ($AnyEvent::VERBOSE);	528	$FILTER->level ($AnyEvent::VERBOSE);
352	$root->log_cb (sub {	529
353	print STDERR shift;	530	$COLLECT->slaves ($FILTER);
354	0	531	$COLLECT->title ('$AnyEvent::Log::COLLECT');
355	});	532
356	$CTX{""} = $root;	533	_reassess;
357	}	534	}
		535
		536	# create the default logger contexts
		537	$LOG = ctx undef;
		538	$FILTER = ctx undef;
		539	$COLLECT = ctx undef;
		540
		541	AnyEvent::Log::reset;
		542
		543	# hello, CPAN, please catch me
		544	package AnyEvent::Log::LOG;
		545	package AE::Log::LOG;
		546	package AnyEvent::Log::FILTER;
		547	package AE::Log::FILTER;
		548	package AnyEvent::Log::COLLECT;
		549	package AE::Log::COLLECT;
358		550
359	package AnyEvent::Log::Ctx;	551	package AnyEvent::Log::Ctx;
360		552
361	# 0 1 2 3 4	553	# 0 1 2 3 4
362	# [$title, $level, %$parents, &$logcb, &$fmtcb]	554	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
		555
		556	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
		557
		558	This is a convenience constructor that makes it simpler to construct
		559	anonymous logging contexts.
		560
		561	Each key-value pair results in an invocation of the method of the same
		562	name as the key with the value as parameter, unless the value is an
		563	arrayref, in which case it calls the method with the contents of the
		564	array. The methods are called in the same order as specified.
		565
		566	Example: create a new logging context and set both the default logging
		567	level, some slave contexts and a logging callback.
		568
		569	$ctx = new AnyEvent::Log::Ctx
		570	title => "dubious messages",
		571	level => "error",
		572	log_cb => sub { print STDOUT shift; 0 },
		573	slaves => [$ctx1, $ctx, $ctx2],
		574	;
		575
		576	=back
		577
		578	=cut
		579
		580	sub new {
		581	my $class = shift;
		582
		583	my $ctx = AnyEvent::Log::ctx undef;
		584
		585	while (@_) {
		586	my ($k, $v) = splice @_, 0, 2;
		587	$ctx->$k (ref $v eq "ARRAY" ? @$v : $v);
		588	}
		589
		590	bless $ctx, $class # do we really support subclassing, hmm?
		591	}
		592
		593
		594	=head2 CONFIGURING A LOG CONTEXT
		595
		596	The following methods can be used to configure the logging context.
		597
		598	=over 4
363		599
364	=item $ctx->title ([$new_title])	600	=item $ctx->title ([$new_title])
365		601
366	Returns the title of the logging context - this is the package name, for	602	Returns the title of the logging context - this is the package name, for
367	package contexts, and a user defined string for all others.	603	package contexts, and a user defined string for all others.
…		…
373	sub title {	609	sub title {
374	$_[0][0] = $_[1] if @_ > 1;	610	$_[0][0] = $_[1] if @_ > 1;
375	$_[0][0]	611	$_[0][0]
376	}	612	}
377		613
		614	=back
		615
		616	=head3 LOGGING LEVELS
		617
		618	The following methods deal with the logging level set associated with the
		619	log context.
		620
		621	The most common method to use is probably C<< $ctx->level ($level) >>,
		622	which configures the specified and any higher priority levels.
		623
		624	All functions which accept a list of levels also accept the special string
		625	C<all> which expands to all logging levels.
		626
		627	=over 4
		628
378	=item $ctx->levels ($level[, $level...)	629	=item $ctx->levels ($level[, $level...)
379		630
380	Enables logging fot the given levels and disables it for all others.	631	Enables logging for the given levels and disables it for all others.
381		632
382	=item $ctx->level ($level)	633	=item $ctx->level ($level)
383		634
384	Enables logging for the given level and all lower level (higher priority)	635	Enables logging for the given level and all lower level (higher priority)
385	ones. Specifying a level of C<0> or C<off> disables all logging for this	636	ones. In addition to normal logging levels, specifying a level of C<0> or
386	level.	637	C<off> disables all logging for this level.
387		638
388	Example: log warnings, errors and higher priority messages.	639	Example: log warnings, errors and higher priority messages.
389		640
390	$ctx->level ("warn");	641	$ctx->level ("warn");
391	$ctx->level (5); # same thing, just numeric	642	$ctx->level (5); # same thing, just numeric
…		…
399	Disables logging for the given levels, leaving all others unchanged.	650	Disables logging for the given levels, leaving all others unchanged.
400		651
401	=cut	652	=cut
402		653
403	sub _lvl_lst {	654	sub _lvl_lst {
		655	map {
		656	$_ > 0 && $_ <= 9 ? $_+0
		657	: $_ eq "all" ? (1 .. 9)
404	map { $_ > 0 && $_ <= 9 ? $_+0 : $STR2LEVEL{$_} \|\| Carp::croak "$_: not a valid logging level, caught" }	658	: $STR2LEVEL{$_} \|\| Carp::croak "$_: not a valid logging level, caught"
405	@_	659	} @_
406	}	660	}
407		661
408	our $NOP_CB = sub { 0 };	662	our $NOP_CB = sub { 0 };
409		663
410	sub levels {	664	sub levels {
…		…
415	AnyEvent::Log::_reassess;	669	AnyEvent::Log::_reassess;
416	}	670	}
417		671
418	sub level {	672	sub level {
419	my $ctx = shift;	673	my $ctx = shift;
420	my $lvl = $_[0] =~ /^(?:0\|off\|none)$/ ? 0 : (_lvl_lst $_[0])[0];	674	my $lvl = $_[0] =~ /^(?:0\|off\|none)$/ ? 0 : (_lvl_lst $_[0])[-1];
		675
421	$ctx->[1] = ((1 << $lvl) - 1) << 1;	676	$ctx->[1] = ((1 << $lvl) - 1) << 1;
422	AnyEvent::Log::_reassess;	677	AnyEvent::Log::_reassess;
423	}	678	}
424		679
425	sub enable {	680	sub enable {
…		…
434	$ctx->[1] &= ~(1 << $_)	689	$ctx->[1] &= ~(1 << $_)
435	for &_lvl_lst;	690	for &_lvl_lst;
436	AnyEvent::Log::_reassess;	691	AnyEvent::Log::_reassess;
437	}	692	}
438		693
		694	=back
		695
		696	=head3 SLAVE CONTEXTS
		697
		698	The following methods attach and detach another logging context to a
		699	logging context.
		700
		701	Log messages are propagated to all slave contexts, unless the logging
		702	callback consumes the message.
		703
		704	=over 4
		705
439	=item $ctx->attach ($ctx2[, $ctx3...])	706	=item $ctx->attach ($ctx2[, $ctx3...])
440		707
441	Attaches the given contexts as parents to this context. It is not an error	708	Attaches the given contexts as slaves to this context. It is not an error
442	to add a context twice (the second add will be ignored).	709	to add a context twice (the second add will be ignored).
443		710
444	A context can be specified either as package name or as a context object.	711	A context can be specified either as package name or as a context object.
445		712
446	=item $ctx->detach ($ctx2[, $ctx3...])	713	=item $ctx->detach ($ctx2[, $ctx3...])
447		714
448	Removes the given parents from this context - it's not an error to attempt	715	Removes the given slaves from this context - it's not an error to attempt
449	to remove a context that hasn't been added.	716	to remove a context that hasn't been added.
450		717
451	A context can be specified either as package name or as a context object.	718	A context can be specified either as package name or as a context object.
		719
		720	=item $ctx->slaves ($ctx2[, $ctx3...])
		721
		722	Replaces all slaves attached to this context by the ones given.
452		723
453	=cut	724	=cut
454		725
455	sub attach {	726	sub attach {
456	my $ctx = shift;	727	my $ctx = shift;
…		…
464		735
465	delete $ctx->[2]{$_+0}	736	delete $ctx->[2]{$_+0}
466	for map { AnyEvent::Log::ctx $_ } @_;	737	for map { AnyEvent::Log::ctx $_ } @_;
467	}	738	}
468		739
		740	sub slaves {
		741	undef $_[0][2];
		742	&attach;
		743	}
		744
		745	=back
		746
		747	=head3 LOG TARGETS
		748
		749	The following methods configure how the logging context actually does
		750	the logging (which consists of formatting the message and printing it or
		751	whatever it wants to do with it).
		752
		753	=over 4
		754
469	=item $ctx->log_cb ($cb->($str))	755	=item $ctx->log_cb ($cb->($str)
470		756
471	Replaces the logging callback on the context (C<undef> disables the	757	Replaces the logging callback on the context (C<undef> disables the
472	logging callback).	758	logging callback).
473		759
474	The logging callback is responsible for handling formatted log messages	760	The logging callback is responsible for handling formatted log messages
475	(see C<fmt_cb> below) - normally simple text strings that end with a	761	(see C<fmt_cb> below) - normally simple text strings that end with a
476	newline (and are possibly multiline themselves).	762	newline (and are possibly multiline themselves).
477		763
478	It also has to return true iff it has consumed the log message, and false	764	It also has to return true iff it has consumed the log message, and false
479	if it hasn't. Consuming a message means that it will not be sent to any	765	if it hasn't. Consuming a message means that it will not be sent to any
480	parent context. When in doubt, return C<0> from your logging callback.	766	slave context. When in doubt, return C<0> from your logging callback.
481		767
482	Example: a very simple logging callback, simply dump the message to STDOUT	768	Example: a very simple logging callback, simply dump the message to STDOUT
483	and do not consume it.	769	and do not consume it.
484		770
485	$ctx->log_cb (sub { print STDERR shift; 0 });	771	$ctx->log_cb (sub { print STDERR shift; 0 });
486		772
		773	You can filter messages by having a log callback that simply returns C<1>
		774	and does not do anything with the message, but this counts as "message
		775	being logged" and might not be very efficient.
		776
		777	Example: propagate all messages except for log levels "debug" and
		778	"trace". The messages will still be generated, though, which can slow down
		779	your program.
		780
		781	$ctx->levels ("debug", "trace");
		782	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages
		783
487	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	784	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $orig_ctx, $level, $message))
488		785
489	Replaces the fornatting callback on the cobntext (C<undef> restores the	786	Replaces the formatting callback on the context (C<undef> restores the
490	default formatter).	787	default formatter).
491		788
492	The callback is passed the (possibly fractional) timestamp, the original	789	The callback is passed the (possibly fractional) timestamp, the original
493	logging context, the (numeric) logging level and the raw message string and needs to	790	logging context, the (numeric) logging level and the raw message string
494	return a formatted log message. In most cases this will be a string, but	791	and needs to return a formatted log message. In most cases this will be a
495	it could just as well be an array reference that just stores the values.	792	string, but it could just as well be an array reference that just stores
		793	the values.
		794
		795	If, for some reason, you want to use C<caller> to find out more baout the
		796	logger then you should walk up the call stack until you are no longer
		797	inside the C<AnyEvent::Log> package.
496		798
497	Example: format just the raw message, with numeric log level in angle	799	Example: format just the raw message, with numeric log level in angle
498	brackets.	800	brackets.
499		801
500	$ctx->fmt_cb (sub {	802	$ctx->fmt_cb (sub {
…		…
517	"$msg->[3]";	819	"$msg->[3]";
518		820
519	0	821	0
520	});	822	});
521		823
		824	=item $ctx->log_to_warn
		825
		826	Sets the C<log_cb> to simply use C<CORE::warn> to report any messages
		827	(usually this logs to STDERR).
		828
		829	=item $ctx->log_to_file ($path)
		830
		831	Sets the C<log_cb> to log to a file (by appending), unbuffered.
		832
		833	=item $ctx->log_to_path ($path)
		834
		835	Same as C<< ->log_to_file >>, but opens the file for each message. This
		836	is much slower, but allows you to change/move/rename/delete the file at
		837	basically any time.
		838
		839	Needless(?) to say, if you do not want to be bitten by some evil person
		840	calling C<chdir>, the path should be absolute. Doesn't help with
		841	C<chroot>, but hey...
		842
		843	=item $ctx->log_to_syslog ([$log_flags])
		844
		845	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and all
		846	the others in the obvious way. If specified, then the C<$log_flags> are
		847	simply or'ed onto the priority argument and can contain any C<LOG_xxx>
		848	flags valid for Sys::Syslog::syslog, except for the priority levels.
		849
		850	Note that this function also sets a C<fmt_cb> - the logging part requires
		851	an array reference with [$level, $str] as input.
		852
522	=cut	853	=cut
523		854
524	sub log_cb {	855	sub log_cb {
525	my ($ctx, $cb) = @_;	856	my ($ctx, $cb) = @_;
526		857
527	$ctx->[3] = $cb \|\| $default_log_cb;	858	$ctx->[3] = $cb;
528	}	859	}
529		860
530	sub fmt_cb {	861	sub fmt_cb {
531	my ($ctx, $cb) = @_;	862	my ($ctx, $cb) = @_;
532		863
533	$ctx->[4] = $cb;	864	$ctx->[4] = $cb;
534	}	865	}
535		866
		867	sub log_to_warn {
		868	my ($ctx, $path) = @_;
		869
		870	$ctx->log_cb (sub {
		871	warn shift;
		872	0
		873	});
		874	}
		875
		876	sub log_to_file {
		877	my ($ctx, $path) = @_;
		878
		879	open my $fh, ">>", $path
		880	or die "$path: $!";
		881
		882	$ctx->log_cb (sub {
		883	syswrite $fh, shift;
		884	0
		885	});
		886	}
		887
		888	sub log_to_path {
		889	my ($ctx, $path) = @_;
		890
		891	$ctx->log_cb (sub {
		892	open my $fh, ">>", $path
		893	or die "$path: $!";
		894
		895	syswrite $fh, shift;
		896	0
		897	});
		898	}
		899
		900	sub log_to_syslog {
		901	my ($ctx, $flags) = @_;
		902
		903	require Sys::Syslog;
		904
		905	$ctx->fmt_cb (sub {
		906	my $str = $_[3];
		907	$str =~ s/\n(?=.)/\n+ /g;
		908
		909	[$_[2], "($_[1][0]) $str"]
		910	});
		911
		912	$ctx->log_cb (sub {
		913	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;
		914
		915	Sys::Syslog::syslog ($flags \| ($lvl - 1), $_)
		916	for split /\n/, $_[0][1];
		917
		918	0
		919	});
		920	}
		921
		922	=back
		923
		924	=head3 MESSAGE LOGGING
		925
		926	These methods allow you to log messages directly to a context, without
		927	going via your package context.
		928
		929	=over 4
		930
536	=item $ctx->log ($level, $msg[, @params])	931	=item $ctx->log ($level, $msg[, @params])
537		932
538	Same as C<AnyEvent::Log::log>, but uses the given context as log context.	933	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
539		934
540	=item $logger = $ctx->logger ($level[, \$enabled])	935	=item $logger = $ctx->logger ($level[, \$enabled])
…		…
545	=cut	940	=cut
546		941
547	*log = \&AnyEvent::Log::_log;	942	*log = \&AnyEvent::Log::_log;
548	*logger = \&AnyEvent::Log::_logger;	943	*logger = \&AnyEvent::Log::_logger;
549		944
		945	=back
		946
		947	=cut
		948
		949	package AnyEvent::Log;
		950
		951	=head1 CONFIGURATION VIA $ENV{PERL_ANYEVENT_LOG}
		952
		953	Logging can also be configured by setting the environment variable
		954	C<PERL_ANYEVENT_LOG> (or C<AE_LOG>).
		955
		956	The value consists of one or more logging context specifications separated
		957	by C<:> or whitespace. Each logging specification in turn starts with a
		958	context name, followed by C<=>, followed by zero or more comma-separated
		959	configuration directives, here are some examples:
		960
		961	# set default logging level
		962	filter=warn
		963
		964	# log to file instead of to stderr
		965	log=file=/tmp/mylog
		966
		967	# log to file in addition to stderr
		968	log=+%file:%file=file=/tmp/mylog
		969
		970	# enable debug log messages, log warnings and above to syslog
		971	filter=debug:log=+%warnings:%warnings=warn,syslog=LOG_LOCAL0
		972
		973	# log trace messages (only) from AnyEvent::Debug to file
		974	AnyEvent::Debug=+%trace:%trace=only,trace,file=/tmp/tracelog
		975
		976	A context name in the log specification can be any of the following:
		977
		978	=over 4
		979
		980	=item C<collect>, C<filter>, C<log>
		981
		982	Correspond to the three predefined C<$AnyEvent::Log::COLLECT>,
		983	C<AnyEvent::Log::FILTER> and C<$AnyEvent::Log::LOG> contexts.
		984
		985	=item C<%name>
		986
		987	Context names starting with a C<%> are anonymous contexts created when the
		988	name is first mentioned. The difference to package contexts is that by
		989	default they have no attached slaves.
		990
		991	=item a perl package name
		992
		993	Any other string references the logging context associated with the given
		994	Perl C<package>. In the unlikely case where you want to specify a package
		995	context that matches on of the other context name forms, you can add a
		996	C<::> to the package name to force interpretation as a package.
		997
		998	=back
		999
		1000	The configuration specifications can be any number of the following:
		1001
		1002	=over 4
		1003
		1004	=item C<stderr>
		1005
		1006	Configures the context to use Perl's C<warn> function (which typically
		1007	logs to C<STDERR>). Works like C<log_to_warn>.
		1008
		1009	=item C<file=>I<path>
		1010
		1011	Configures the context to log to a file with the given path. Works like
		1012	C<log_to_file>.
		1013
		1014	=item C<path=>I<path>
		1015
		1016	Configures the context to log to a file with the given path. Works like
		1017	C<log_to_path>.
		1018
		1019	=item C<syslog> or C<syslog=>I<expr>
		1020
		1021	Configures the context to log to syslog. If I<expr> is given, then it is
		1022	evaluated in the L<Sys::Syslog> package, so you could use:
		1023
		1024	log=syslog=LOG_LOCAL0
		1025
		1026	=item C<nolog>
		1027
		1028	Configures the context to not log anything by itself, which is the
		1029	default. Same as C<< $ctx->log_cb (undef) >>.
		1030
		1031	=item C<0> or C<off>
		1032
		1033	Sets the logging level of the context ot C<0>, i.e. all messages will be
		1034	filtered out.
		1035
		1036	=item C<all>
		1037
		1038	Enables all logging levels, i.e. filtering will effectively be switched
		1039	off (the default).
		1040
		1041	=item C<only>
		1042
		1043	Disables all logging levels, and changes the interpretation of following
		1044	level specifications to enable the specified level only.
		1045
		1046	Example: only enable debug messages for a context.
		1047
		1048	context=only,debug
		1049
		1050	=item C<except>
		1051
		1052	Enables all logging levels, and changes the interpretation of following
		1053	level specifications to disable that level. Rarely used.
		1054
		1055	Example: enable all logging levels except fatal and trace (this is rather
		1056	nonsensical).
		1057
		1058	filter=exept,fatal,trace
		1059
		1060	=item C<level>
		1061
		1062	Enables all logging levels, and changes the interpretation of following
		1063	level specifications to be "that level or any higher priority
		1064	message". This is the default.
		1065
		1066	Example: log anything at or above warn level.
		1067
		1068	filter=warn
		1069
		1070	# or, more verbose
		1071	filter=only,level,warn
		1072
		1073	=item C<1>..C<9> or a logging level name (C<error>, C<debug> etc.)
		1074
		1075	A numeric loglevel or the name of a loglevel will be interpreted according
		1076	to the most recent C<only>, C<except> or C<level> directive. By default,
		1077	specifying a logging level enables that and any higher priority messages.
		1078
		1079	=item C<+>I<context>
		1080
		1081	Attaches the named context as slave to the context.
		1082
		1083	=item C<+>
		1084
		1085	A line C<+> detaches all contexts, i.e. clears the slave list from the
		1086	context. Anonymous (C<%name>) contexts have no attached slaves by default,
		1087	but package contexts have the parent context as slave by default.
		1088
		1089	Example: log messages from My::Module to a file, do not send them to the
		1090	default log collector.
		1091
		1092	My::Module=+,file=/tmp/mymodulelog
		1093
		1094	=back
		1095
		1096	Any character can be escaped by prefixing it with a C<\> (backslash), as
		1097	usual, so to log to a file containing a comma, colon, backslash and some
		1098	spaces in the filename, you would do this:
		1099
		1100	PERL_ANYEVENT_LOG='log=file=/some\ \:file\ with\,\ \\-escapes'
		1101
		1102	Since whitespace (which includes newlines) is allowed, it is fine to
		1103	specify multiple lines in C<PERL_ANYEVENT_LOG>, e.g.:
		1104
		1105	PERL_ANYEVENT_LOG="
		1106	filter=warn
		1107	AnyEvent::Debug=+%trace
		1108	%trace=only,trace,+log
		1109	" myprog
		1110
		1111	Also, in the unlikely case when you want to concatenate specifications,
		1112	use whitespace as separator, as C<::> will be interpreted as part of a
		1113	module name, an empty spec with two separators:
		1114
		1115	PERL_ANYEVENT_LOG="$PERL_ANYEVENT_LOG MyMod=debug"
		1116
		1117	=cut
		1118
		1119	for (my $spec = $ENV{PERL_ANYEVENT_LOG}) {
		1120	my %anon;
		1121
		1122	my $pkg = sub {
		1123	$_[0] eq "log" ? $LOG
		1124	: $_[0] eq "filter" ? $FILTER
		1125	: $_[0] eq "collect" ? $COLLECT
		1126	: $_[0] =~ /^%(.+)$/ ? ($anon{$1} \|\|= ctx undef)
		1127	: $_[0] =~ /^(.*?)(?:::)?$/ ? ctx "$1" # egad :/
		1128	: die # never reached?
		1129	};
		1130
		1131	/\G[[:space:]]+/gc; # skip initial whitespace
		1132
		1133	while (/\G((?:[^:=[:space:]]+\|::\|\\.)+)=/gc) {
		1134	my $ctx = $pkg->($1);
		1135	my $level = "level";
		1136
		1137	while (/\G((?:[^,:[:space:]]+\|::\|\\.)+)/gc) {
		1138	for ("$1") {
		1139	if ($_ eq "stderr" ) { $ctx->log_to_warn;
		1140	} elsif (/^file=(.+)/ ) { $ctx->log_to_file ("$1");
		1141	} elsif (/^path=(.+)/ ) { $ctx->log_to_path ("$1");
		1142	} elsif (/syslog(?:=(.*))?/ ) { require Sys::Syslog; $ctx->log_to_syslog (eval "package Sys::Syslog; $1");
		1143	} elsif ($_ eq "nolog" ) { $ctx->log_cb (undef);
		1144	} elsif (/^\+(.+)$/ ) { $ctx->attach ($pkg->("$1"));
		1145	} elsif ($_ eq "+" ) { $ctx->slaves;
		1146	} elsif ($_ eq "off" or $_ eq "0") { $ctx->level (0);
		1147	} elsif ($_ eq "all" ) { $ctx->level ("all");
		1148	} elsif ($_ eq "level" ) { $ctx->level ("all"); $level = "level";
		1149	} elsif ($_ eq "only" ) { $ctx->level ("off"); $level = "enable";
		1150	} elsif ($_ eq "except" ) { $ctx->level ("all"); $level = "disable";
		1151	} elsif (/^\d$/ ) { $ctx->$level ($_);
		1152	} elsif (exists $STR2LEVEL{$_} ) { $ctx->$level ($_);
		1153	} else { die "PERL_ANYEVENT_LOG ($spec): parse error at '$_'\n";
		1154	}
		1155	}
		1156
		1157	/\G,/gc or last;
		1158	}
		1159
		1160	/\G[:[:space:]]+/gc or last;
		1161	}
		1162
		1163	/\G[[:space:]]+/gc; # skip trailing whitespace
		1164
		1165	if (/\G(.+)/g) {
		1166	die "PERL_ANYEVENT_LOG ($spec): parse error at '$1'\n";
		1167	}
		1168	}
		1169
550	1;	1170	1;
		1171
		1172	=head1 EXAMPLES
		1173
		1174	This section shows some common configurations, both as code, and as
		1175	C<PERL_ANYEVENT_LOG> string.
		1176
		1177	=over 4
		1178
		1179	=item Setting the global logging level.
		1180
		1181	Either put C<PERL_ANYEVENT_VERBOSE=><number> into your environment before
		1182	running your program, use C<PERL_ANYEVENT_LOG> or modify the log level of
		1183	the root context at runtime:
		1184
		1185	PERL_ANYEVENT_VERBOSE=5 ./myprog
		1186
		1187	PERL_ANYEVENT_LOG=log=warn
		1188
		1189	$AnyEvent::Log::FILTER->level ("warn");
		1190
		1191	=item Append all messages to a file instead of sending them to STDERR.
		1192
		1193	This is affected by the global logging level.
		1194
		1195	$AnyEvent::Log::LOG->log_to_file ($path);
		1196
		1197	PERL_ANYEVENT_LOG=log=file=/some/path
		1198
		1199	=item Write all messages with priority C<error> and higher to a file.
		1200
		1201	This writes them only when the global logging level allows it, because
		1202	it is attached to the default context which is invoked I<after> global
		1203	filtering.
		1204
		1205	$AnyEvent::Log::FILTER->attach
		1206	new AnyEvent::Log::Ctx log_to_file => $path);
		1207
		1208	PERL_ANYEVENT_LOG=filter=+%filelogger:%filelogger=file=/some/path
		1209
		1210	This writes them regardless of the global logging level, because it is
		1211	attached to the toplevel context, which receives all messages I<before>
		1212	the global filtering.
		1213
		1214	$AnyEvent::Log::COLLECT->attach (
		1215	new AnyEvent::Log::Ctx log_to_file => $path);
		1216
		1217	PERL_ANYEVENT_LOG=%filelogger=file=/some/path:collect=+%filelogger
		1218
		1219	In both cases, messages are still written to STDERR.
		1220
		1221	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
		1222
		1223	Attach the C<$AnyEvent::Log::LOG> context to the C<AnyEvent::Debug>
		1224	context - this simply circumvents the global filtering for trace messages.
		1225
		1226	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
		1227	$debug->attach ($AnyEvent::Log::LOG);
		1228
		1229	PERL_ANYEVENT_LOG=AnyEvent::Debug=+log
		1230
		1231	This of course works for any package, not just L<AnyEvent::Debug>, but
		1232	assumes the log level for AnyEvent::Debug hasn't been changed from the
		1233	default.
551		1234
552	=back	1235	=back
553		1236
554	=head1 AUTHOR	1237	=head1 AUTHOR
555		1238
556	Marc Lehmann <schmorp@schmorp.de>	1239	Marc Lehmann <schmorp@schmorp.de>
557	http://home.schmorp.de/	1240	http://home.schmorp.de/
558		1241
559	=cut	1242	=cut
		1243

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents): Revision 1.8 by root, Fri Aug 19 19:20:36 2011 UTC vs. Revision 1.37 by root, Thu Aug 25 06:34:11 2011 UTC

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.8 by root, Fri Aug 19 19:20:36 2011 UTC vs.
Revision 1.37 by root, Thu Aug 25 06:34:11 2011 UTC