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

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.15 by root, Sat Aug 20 02:16:59 2011 UTC vs.
Revision 1.41 by root, Thu Sep 1 04:07:18 2011 UTC

…		…
2		2
3	AnyEvent::Log - simple logging "framework"	3	AnyEvent::Log - simple logging "framework"
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	# simple use	7	Simple uses:
		8
8	use AnyEvent;	9	use AnyEvent;
9		10
10	AE::log debug => "hit my knee";	11	AE::log debug => "hit my knee";
11	AE::log warn => "it's a bit too hot";	12	AE::log warn => "it's a bit too hot";
12	AE::log error => "the flag was false!";	13	AE::log error => "the flag was false!";
13	AE::log fatal => "the bit toggled! run!";	14	AE::log fatal => "the bit toggled! run!"; # never returns
14		15
15	# "complex" use	16	# available log levels in order:
		17	# fatal alert critical error warn note info debug trace
		18
		19	"Complex" uses (for speed sensitive code):
		20
16	use AnyEvent::Log;	21	use AnyEvent::Log;
17		22
18	my $tracer = AnyEvent::Log::logger trace => \$my $trace;	23	my $tracer = AnyEvent::Log::logger trace => \$my $trace;
19		24
20	$tracer->("i am here") if $trace;	25	$tracer->("i am here") if $trace;
21	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;	26	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;
22		27
23	# configuration	28	Configuration (also look at the EXAMPLES section):
24		29
25	# set logging for this package to maximum	30	# set logging for the current package to errors and higher only
26	AnyEvent::Log::ctx->level ("all");	31	AnyEvent::Log::ctx->level ("error");
27		32
28	# set logging globally to anything below debug	33	# set logging level to suppress anything below "notice"
29	(AnyEvent::Log::ctx "")->level ("notice");	34	$AnyEvent::Log::FILTER->level ("notice");
30		35
31	# see also EXAMPLES, below	36	# send all critical and higher priority messages to syslog,
32		37	# regardless of (most) other settings
33	# disable logging for package "AnyEvent" and all packages below it	38	$AnyEvent::Log::COLLECT->attach (new AnyEvent::Log::Ctx
34	AnyEvent->AnyEvent::Log::ctx->level (0);	39	level => "critical",
35		40	log_to_syslog => "user",
36	# log everything below debug to a file, for the whole program	41	);
37	my $ctx = AnyEvent::Log::ctx;
38	$ctx->log_cb (sub { print FILE shift; 0 });
39	(AnyEvent::Log::ctx "")->add ($ctx);
40		42
41	=head1 DESCRIPTION	43	=head1 DESCRIPTION
42		44
43	This module implements a relatively simple "logging framework". It doesn't	45	This module implements a relatively simple "logging framework". It doesn't
44	attempt to be "the" logging solution or even "a" logging solution for	46	attempt to be "the" logging solution or even "a" logging solution for
45	AnyEvent - AnyEvent simply creates logging messages internally, and this	47	AnyEvent - AnyEvent simply creates logging messages internally, and this
46	module more or less exposes the mechanism, with some extra spiff to allow	48	module more or less exposes the mechanism, with some extra spiff to allow
47	using it from other modules as well.	49	using it from other modules as well.
48		50
49	Remember that the default verbosity level is C<0>, so nothing will be	51	Remember that the default verbosity level is C<0> (C<off>), so nothing
50	logged, unless you set C<PERL_ANYEVENT_VERBOSE> to a higher number before	52	will be logged, unless you set C<PERL_ANYEVENT_VERBOSE> to a higher number
51	starting your program, or change the logging level at runtime with	53	before starting your program, or change the logging level at runtime with
52	something like:	54	something like:
53		55
54	use AnyEvent;	56	use AnyEvent::Log;
55	(AnyEvent::Log::ctx "")->level ("info");	57	$AnyEvent::Log::FILTER->level ("info");
56		58
57	The design goal behind this module was to keep it simple (and small),	59	The design goal behind this module was to keep it simple (and small),
58	but make it powerful enough to be potentially useful for any module, and	60	but make it powerful enough to be potentially useful for any module, and
59	extensive enough for the most common tasks, such as logging to multiple	61	extensive enough for the most common tasks, such as logging to multiple
60	targets, or being able to log into a database.	62	targets, or being able to log into a database.
61		63
		64	The module is also usable before AnyEvent itself is initialised, in which
		65	case some of the functionality might be reduced.
		66
62	The amount of documentation might indicate otherwise, but the module is	67	The amount of documentation might indicate otherwise, but the runtime part
63	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 aborts program!
		81	2 alert
		82	3 critical crit
		83	4 error err die
		84	5 warn warning
		85	6 note notice
		86	7 info
		87	8 debug
		88	9 trace
		89
		90	As you can see, some logging levels have multiple aliases - the first one
		91	is the "official" name, the second one the "syslog" name (if it differs)
		92	and the third one the "perl" name, suggesting (only!) that you log C<die>
		93	messages at C<error> priority.
		94
		95	You can normally only log a single message at highest priority level
		96	(C<1>, C<fatal>), because logging a fatal message will also quit the
		97	program - so use it sparingly :)
		98
		99	Some methods also offer some extra levels, such as C<0>, C<off>, C<none>
		100	or C<all> - these are only valid in the methods they are documented for.
64		101
65	=head1 LOGGING FUNCTIONS	102	=head1 LOGGING FUNCTIONS
66		103
67	These functions allow you to log messages. They always use the caller's	104	These functions allow you to log messages. They always use the caller's
68	package as a "logging module/source". Also, the main logging function is	105	package as a "logging context". Also, the main logging function C<log> is
69	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is	106	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is
70	loaded.	107	loaded.
71		108
72	=over 4	109	=over 4
73		110
…		…
77		114
78	use Carp ();	115	use Carp ();
79	use POSIX ();	116	use POSIX ();
80		117
81	use AnyEvent (); BEGIN { AnyEvent::common_sense }	118	use AnyEvent (); BEGIN { AnyEvent::common_sense }
82	use AnyEvent::Util ();	119	#use AnyEvent::Util (); need to load this in a delayed fashion, as it uses AE::log
83		120
84	our $VERSION = $AnyEvent::VERSION;	121	our $VERSION = $AnyEvent::VERSION;
		122
		123	our ($COLLECT, $FILTER, $LOG);
85		124
86	our ($now_int, $now_str1, $now_str2);	125	our ($now_int, $now_str1, $now_str2);
87		126
88	# Format Time, not public - yet?	127	# Format Time, not public - yet?
89	sub ft($) {	128	sub ft($) {
…		…
94	if $now_int != $i;	133	if $now_int != $i;
95		134
96	"$now_str1$f$now_str2"	135	"$now_str1$f$now_str2"
97	}	136	}
98		137
99	our %CTX; # all logging contexts	138	our %CTX; # all package contexts
100		139
101	# creates a default package context object for the given package	140	# creates a default package context object for the given package
102	sub _pkg_ctx($) {	141	sub _pkg_ctx($) {
103	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";	142	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";
104		143
105	# link "parent" package	144	# link "parent" package
106	my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "AE::Log::Top";	145	my $parent = $_[0] =~ /^(.+)::/
		146	? $CTX{$1} \|\|= &_pkg_ctx ("$1")
		147	: $COLLECT;
107		148
108	$pkg = $CTX{$pkg} \|\|= &_pkg_ctx ($pkg);
109	$ctx->[2]{$pkg+0} = $pkg;	149	$ctx->[2]{$parent+0} = $parent;
110		150
111	$ctx	151	$ctx
112	}	152	}
113		153
114	=item AnyEvent::Log::log $level, $msg[, @args]	154	=item AnyEvent::Log::log $level, $msg[, @args]
115		155
116	Requests logging of the given C<$msg> with the given log level (1..9).	156	Requests logging of the given C<$msg> with the given log level, and
117	You can also use the following strings as log level: C<fatal> (1),	157	returns true if the message was logged I<somewhere>.
118	C<alert> (2), C<critical> (3), C<error> (4), C<warn> (5), C<note> (6),
119	C<info> (7), C<debug> (8), C<trace> (9).
120		158
121	For C<fatal> log levels, the program will abort.	159	For loglevel C<fatal>, the program will abort.
122		160
123	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the	161	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the
124	C<$msg> is interpreted as an sprintf format string.	162	C<$msg> is interpreted as an sprintf format string.
125		163
126	The C<$msg> should not end with C<\n>, but may if that is convenient for	164	The C<$msg> should not end with C<\n>, but may if that is convenient for
…		…
130	supposed to return the message. It will be called only then the message	168	supposed to return the message. It will be called only then the message
131	actually gets logged, which is useful if it is costly to create the	169	actually gets logged, which is useful if it is costly to create the
132	message in the first place.	170	message in the first place.
133		171
134	Whether the given message will be logged depends on the maximum log level	172	Whether the given message will be logged depends on the maximum log level
135	and the caller's package.	173	and the caller's package. The return value can be used to ensure that
		174	messages or not "lost" - for example, when L<AnyEvent::Debug> detects a
		175	runtime error it tries to log it at C<die> level, but if that message is
		176	lost it simply uses warn.
136		177
137	Note that you can (and should) call this function as C<AnyEvent::log> or	178	Note that you can (and should) call this function as C<AnyEvent::log> or
138	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't	179	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't
139	need any additional functionality), as those functions will load the	180	need any additional functionality), as those functions will load the
140	logging module on demand only. They are also much shorter to write.	181	logging module on demand only. They are also much shorter to write.
…		…
157		198
158	=cut	199	=cut
159		200
160	# also allow syslog equivalent names	201	# also allow syslog equivalent names
161	our %STR2LEVEL = (	202	our %STR2LEVEL = (
162	fatal => 1, emerg => 1,	203	fatal => 1, emerg => 1, exit => 1,
163	alert => 2,	204	alert => 2,
164	critical => 3, crit => 3,	205	critical => 3, crit => 3,
165	error => 4, err => 4,	206	error => 4, err => 4, die => 4,
166	warn => 5, warning => 5,	207	warn => 5, warning => 5,
167	note => 6, notice => 6,	208	note => 6, notice => 6,
168	info => 7,	209	info => 7,
169	debug => 8,	210	debug => 8,
170	trace => 9,	211	trace => 9,
171	);	212	);
172		213
173	sub now () { time }	214	our $TIME_EXACT;
		215
		216	sub exact_time($) {
		217	$TIME_EXACT = shift;
		218	*_ts = $AnyEvent::MODEL
		219	? $TIME_EXACT ? \&AE::now : \&AE::time
		220	: sub () { $TIME_EXACT ? do { require Time::HiRes; Time::HiRes::time () } : time };
		221	}
		222
		223	BEGIN {
		224	exact_time 0;
		225	}
174		226
175	AnyEvent::post_detect {	227	AnyEvent::post_detect {
176	*now = \&AE::now;	228	exact_time $TIME_EXACT;
177	};	229	};
178		230
179	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);	231	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);
180		232
181	# time, ctx, level, msg	233	# time, ctx, level, msg
…		…
200	? $level+0	252	? $level+0
201	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";	253	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";
202		254
203	my $mask = 1 << $level;	255	my $mask = 1 << $level;
204		256
205	my (%seen, @ctx, $now, $fmt);	257	my ($success, %seen, @ctx, $now, $fmt);
206		258
207	do	259	do
208	{	260	{
209	# skip if masked	261	# skip if masked
210	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {	262	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {
…		…
214	# now get raw message, unless we have it already	266	# now get raw message, unless we have it already
215	unless ($now) {	267	unless ($now) {
216	$format = $format->() if ref $format;	268	$format = $format->() if ref $format;
217	$format = sprintf $format, @args if @args;	269	$format = sprintf $format, @args if @args;
218	$format =~ s/\n$//;	270	$format =~ s/\n$//;
219	$now = AE::now;	271	$now = _ts;
220	};	272	};
221		273
222	# format msg	274	# format msg
223	my $str = $ctx->[4]	275	my $str = $ctx->[4]
224	? $ctx->[4]($now, $_[0], $level, $format)	276	? $ctx->[4]($now, $_[0], $level, $format)
225	: $fmt \|\|= _format $now, $_[0], $level, $format;	277	: ($fmt \|\|= _format $now, $_[0], $level, $format);
226		278
		279	$success = 1;
		280
227	$ctx->[3]($str);	281	$ctx->[3]($str)
		282	or push @ctx, values %{ $ctx->[2] }; # not consumed - propagate
		283	} else {
		284	push @ctx, values %{ $ctx->[2] }; # not masked - propagate
228	}	285	}
229
230	# not masked, not consumed - propagate to parent contexts
231	push @ctx, values %{ $ctx->[2] };
232	}	286	}
233	}	287	}
234	while $ctx = pop @ctx;	288	while $ctx = pop @ctx;
235		289
236	exit 1 if $level <= 1;	290	exit 1 if $level <= 1;
		291
		292	$success
237	}	293	}
238		294
239	sub log($$;@) {	295	sub log($$;@) {
240	_log	296	_log
241	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	297	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
…		…
245	AnyEvent::log = AE::log = \&log;	301	AnyEvent::log = AE::log = \&log;
246		302
247	=item $logger = AnyEvent::Log::logger $level[, \$enabled]	303	=item $logger = AnyEvent::Log::logger $level[, \$enabled]
248		304
249	Creates a code reference that, when called, acts as if the	305	Creates a code reference that, when called, acts as if the
250	C<AnyEvent::Log::log> function was called at this point with the givne	306	C<AnyEvent::Log::log> function was called at this point with the given
251	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with	307	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with
252	the C<AnyEvent::Log::log> function:	308	the C<AnyEvent::Log::log> function:
253		309
254	my $debug_log = AnyEvent::Log::logger "debug";	310	my $debug_log = AnyEvent::Log::logger "debug";
255		311
…		…
280	# and later in your program	336	# and later in your program
281	$debug_log->("yo, stuff here") if $debug;	337	$debug_log->("yo, stuff here") if $debug;
282		338
283	$debug and $debug_log->("123");	339	$debug and $debug_log->("123");
284		340
285	Note: currently the enabled var is always true - that will be fixed in a
286	future version :)
287
288	=cut	341	=cut
289		342
290	our %LOGGER;	343	our %LOGGER;
291		344
292	# re-assess logging status for all loggers	345	# re-assess logging status for all loggers
293	sub _reassess {	346	sub _reassess {
		347	local $SIG{__DIE__};
		348	my $die = sub { die };
		349
294	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {	350	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {
295	my ($ctx, $level, $renabled) = @$_;	351	my ($ctx, $level, $renabled) = @$_;
296		352
297	# to detect whether a message would be logged, we # actually	353	# to detect whether a message would be logged, we actually
298	# try to log one and die. this isn't fast, but we can be	354	# try to log one and die. this isn't fast, but we can be
299	# sure that the logging decision is correct :)	355	# sure that the logging decision is correct :)
300		356
301	$$renabled = !eval {	357	$$renabled = !eval {
302	local $SIG{__DIE__};
303
304	_log $ctx, $level, sub { die };	358	_log $ctx, $level, $die;
305		359
306	1	360	1
307	};	361	};
308
309	$$renabled = 1; # TODO
310	}	362	}
311	}	363	}
312		364
313	sub _logger {	365	sub _logger {
314	my ($ctx, $level, $renabled) = @_;	366	my ($ctx, $level, $renabled) = @_;
…		…
319		371
320	$LOGGER{$logger+0} = $logger;	372	$LOGGER{$logger+0} = $logger;
321		373
322	_reassess $logger+0;	374	_reassess $logger+0;
323		375
		376	require AnyEvent::Util;
324	my $guard = AnyEvent::Util::guard {	377	my $guard = AnyEvent::Util::guard (sub {
325	# "clean up"	378	# "clean up"
326	delete $LOGGER{$logger+0};	379	delete $LOGGER{$logger+0};
327	};	380	});
328		381
329	sub {	382	sub {
330	$guard if 0; # keep guard alive, but don't cause runtime overhead	383	$guard if 0; # keep guard alive, but don't cause runtime overhead
331		384
332	_log $ctx, $level, @_	385	_log $ctx, $level, @_
…		…
337	sub logger($;$) {	390	sub logger($;$) {
338	_logger	391	_logger
339	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	392	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
340	@_	393	@_
341	}	394	}
		395
		396	=item AnyEvent::Log::exact_time $on
		397
		398	By default, C<AnyEvent::Log> will use C<AE::now>, i.e. the cached
		399	eventloop time, for the log timestamps. After calling this function with a
		400	true value it will instead resort to C<AE::time>, i.e. fetch the current
		401	time on each log message. This only makes a difference for event loops
		402	that actually cache the time (such as L<EV> or L<AnyEvent::Loop>).
		403
		404	This setting can be changed at any time by calling this function.
		405
		406	Since C<AnyEvent::Log> has to work even before the L<AnyEvent> has been
		407	initialised, this switch will also decide whether to use C<CORE::time> or
		408	C<Time::HiRes::time> when logging a message before L<AnyEvent> becomes
		409	available.
342		410
343	=back	411	=back
344		412
345	=head1 LOGGING CONTEXTS	413	=head1 LOGGING CONTEXTS
346		414
…		…
359	timestamp, context, level and string message and formats it in the way	427	timestamp, context, level and string message and formats it in the way
360	it should be logged) and a logging callback (which is responsible for	428	it should be logged) and a logging callback (which is responsible for
361	actually logging the formatted message and telling C<AnyEvent::Log>	429	actually logging the formatted message and telling C<AnyEvent::Log>
362	whether it has consumed the message, or whether it should be propagated).	430	whether it has consumed the message, or whether it should be propagated).
363		431
364	For propagation, a context can have any number of attached I<parent	432	For propagation, a context can have any number of attached I<slave
365	contexts>. Any message that is neither masked by the logging mask nor	433	contexts>. Any message that is neither masked by the logging mask nor
366	masked by the logging callback returning true will be passed to all parent	434	masked by the logging callback returning true will be passed to all slave
367	contexts.	435	contexts.
368		436
369	Each call to a logging function will log the message at most once per	437	Each call to a logging function will log the message at most once per
370	context, so it does not matter (much) if there are cycles or if the	438	context, so it does not matter (much) if there are cycles or if the
371	message can arrive at the same context via multiple paths.	439	message can arrive at the same context via multiple paths.
…		…
375	By default, all logging contexts have an full set of log levels ("all"), a	443	By default, all logging contexts have an full set of log levels ("all"), a
376	disabled logging callback and the default formatting callback.	444	disabled logging callback and the default formatting callback.
377		445
378	Package contexts have the package name as logging title by default.	446	Package contexts have the package name as logging title by default.
379		447
380	They have exactly one parent - the context of the "parent" package. The	448	They have exactly one slave - the context of the "parent" package. The
381	parent package is simply defined to be the package name without the last	449	parent package is simply defined to be the package name without the last
382	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,	450	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
383	and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the	451	and C<AnyEvent> becomes ... C<$AnyEvent::Log::COLLECT> which is the
384	exception of the rule - just like the parent of any package name in	452	exception of the rule - just like the "parent" of any single-component
385	Perl is C<main>, the default parent of any top-level package context is	453	package name in Perl is C<main>, the default slave of any top-level
386	C<AnyEvent::Log::Top>.	454	package context is C<$AnyEvent::Log::COLLECT>.
387		455
388	Since perl packages form only an approximate hierarchy, this parent	456	Since perl packages form only an approximate hierarchy, this slave
389	context can of course be removed.	457	context can of course be removed.
390		458
391	All other (anonymous) contexts have no parents and an empty title by	459	All other (anonymous) contexts have no slaves and an empty title by
392	default.	460	default.
393		461
394	When the module is loaded it creates the default context called	462	When the module is loaded it creates the C<$AnyEvent::Log::LOG> logging
395	C<AnyEvent::Log::Default> (also stored in C<$AnyEvent::Log::Default>),	463	context that simply logs everything via C<warn>, without propagating
396	which simply logs everything via C<warn> and doesn't propagate anything
397	anywhere by default. The purpose of the default context is to provide	464	anything anywhere by default. The purpose of this context is to provide
398	a convenient place to override the global logging target or to attach	465	a convenient place to override the global logging target or to attach
399	additional log targets. It's not meant for filtering.	466	additional log targets. It's not meant for filtering.
400		467
401	It then creates the root context called C<AnyEvent::Log::Root> (also	468	It then creates the C<$AnyEvent::Log::FILTER> context whose
402	stored in C<$AnyEvent::Log::Root>) and sets its log level set to all	469	purpose is to suppress all messages with priority higher
403	levels up to the one specified by C<$ENV{PERL_ANYEVENT_VERBOSE}>. It	470	than C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the
404	then attached the default logging context to it. The purpose of the root	471	C<$AnyEvent::Log::LOG> context to it. The purpose of the filter context
405	context is to simply provide filtering according to some global log level.	472	is to simply provide filtering according to some global log level.
406		473
407	Finally it creates the top-level package context called	474	Finally it creates the top-level package context C<$AnyEvent::Log::COLLECT>
408	C<AnyEvent::Log::Top> (also stored in, you might have guessed,	475	and attaches the C<$AnyEvent::Log::FILTER> context to it, but otherwise
409	C<$AnyEvent::Log::Top>) and attached the root context but otherwise leaves
410	it at default config. It's purpose is simply to collect all log messages	476	leaves it at default config. Its purpose is simply to collect all log
411	system-wide.	477	messages system-wide.
412		478
413	These three special contexts can also be referred to by the	479	The hierarchy is then:
414	package/context names C<AE::Log::Default>, C<AE::Log::Root> and
415	C<AE::Log::Top>.
416		480
		481	any package, eventually -> $COLLECT -> $FILTER -> $LOG
		482
417	The effect of all this is that log messages, by default, wander up	483	The effect of all this is that log messages, by default, wander up to the
418	to the root context where log messages with lower priority then	484	C<$AnyEvent::Log::COLLECT> context where all messages normally end up,
		485	from there to C<$AnyEvent::Log::FILTER> where log messages with lower
419	C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered away and then to the	486	priority then C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered out and then
420	AnyEvent::Log::Default context to be passed to C<warn>.	487	to the C<$AnyEvent::Log::LOG> context to be passed to C<warn>.
421		488
422	Splitting the top level context into three contexts makes it easy to set	489	This makes it easy to set a global logging level (by modifying $FILTER),
423	a global logging level (by modifying the root context), but still allow	490	but still allow other contexts to send, for example, their debug and trace
424	other contexts to log, for example, their debug and trace messages to the
425	default target despite the global logging level, or to attach additional	491	messages to the $LOG target despite the global logging level, or to attach
426	log targets that log messages, regardless of the global logging level.	492	additional log targets that log messages, regardless of the global logging
		493	level.
427		494
428	It also makes it easy to replace the default warn-logger by something that	495	It also makes it easy to modify the default warn-logger ($LOG) to
429	logs to a file, or to attach additional logging targets.	496	something that logs to a file, or to attach additional logging targets
		497	(such as loggign to a file) by attaching it to $FILTER.
430		498
431	=head2 CREATING/FINDING/DESTROYING CONTEXTS	499	=head2 CREATING/FINDING/DESTROYING CONTEXTS
432		500
433	=over 4	501	=over 4
434		502
…		…
456	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"	524	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"
457	}	525	}
458		526
459	=item AnyEvent::Log::reset	527	=item AnyEvent::Log::reset
460		528
461	Resets all package contexts contexts and recreates the default hierarchy	529	Resets all package contexts and recreates the default hierarchy if
462	if necessary, i.e. resets the logging subsystem to defaults.	530	necessary, i.e. resets the logging subsystem to defaults, as much as
		531	possible. This process keeps references to contexts held by other parts of
		532	the program intact.
463		533
464	This can be used to implement config-file (re-)loading: before loading a	534	This can be used to implement config-file (re-)loading: before loading a
465	configuration, reset all contexts.	535	configuration, reset all contexts.
466		536
467	Note that this currently destroys all logger callbacks - bug me if you
468	need this fixed :)
469
470	=cut	537	=cut
471		538
472	sub reset {	539	sub reset {
473	# hard to kill complex data structures	540	# hard to kill complex data structures
474	# we recreate all package loggers and reset the hierarchy	541	# we "recreate" all package loggers and reset the hierarchy
475	while (my ($k, $v) = each %CTX) {	542	while (my ($k, $v) = each %CTX) {
476	@$v = ($k, (1 << 10) - 1 - 1, { });	543	@$v = ($k, (1 << 10) - 1 - 1, { });
477		544
478	my $pkg = $k =~ /^(.+)::/ ? $1 : "AE::Log::Top";	545	$v->attach ($k =~ /^(.+)::/ ? $CTX{$1} : $AnyEvent::Log::COLLECT);
479	$v->attach ($CTX{$pkg});
480	}	546	}
481		547
482	$AnyEvent::Log::Default->parents;	548	@$_ = ($_->[0], (1 << 10) - 1 - 1)
483	$AnyEvent::Log::Default->title ("AnyEvent::Log::Default");	549	for $LOG, $FILTER, $COLLECT;
484	$AnyEvent::Log::Default->log_cb (sub {
485	warn shift;
486	0
487	});
488	$CTX{"AnyEvent::Log::Default"} = $CTX{"AE::Log::Default"} = $AnyEvent::Log::Default;
489		550
490	$AnyEvent::Log::Root->parents ($AnyEvent::Log::Default);	551	#$LOG->slaves;
491	$AnyEvent::Log::Root->title ("AnyEvent::Log::Root");	552	$LOG->title ('$AnyEvent::Log::LOG');
		553	$LOG->log_to_warn;
		554
		555	$FILTER->slaves ($LOG);
		556	$FILTER->title ('$AnyEvent::Log::FILTER');
492	$AnyEvent::Log::Root->level ($AnyEvent::VERBOSE);	557	$FILTER->level ($AnyEvent::VERBOSE);
493	$CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $AnyEvent::Log::Root;
494		558
495	$AnyEvent::Log::Top->parents ($AnyEvent::Log::Root);	559	$COLLECT->slaves ($FILTER);
496	$AnyEvent::Log::Top->title ("AnyEvent::Log::Top");	560	$COLLECT->title ('$AnyEvent::Log::COLLECT');
497	$CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $AnyEvent::Log::Top;
498		561
499	_reassess;	562	_reassess;
500	}	563	}
501		564
502	# create the default logger contexts	565	# create the default logger contexts
503	$AnyEvent::Log::Default = ctx undef;	566	$LOG = ctx undef;
504	$AnyEvent::Log::Root = ctx undef;	567	$FILTER = ctx undef;
505	$AnyEvent::Log::Top = ctx undef;	568	$COLLECT = ctx undef;
506		569
507	AnyEvent::Log::reset;	570	AnyEvent::Log::reset;
508		571
509	# hello, CPAN, please catch me	572	# hello, CPAN, please catch me
510	package AnyEvent::Log::Default;
511	package AE::Log::Default;
512	package AnyEvent::Log::Root;
513	package AE::Log::Root;
514	package AnyEvent::Log::Top;	573	package AnyEvent::Log::LOG;
515	package AE::Log::Top;	574	package AE::Log::LOG;
		575	package AnyEvent::Log::FILTER;
		576	package AE::Log::FILTER;
		577	package AnyEvent::Log::COLLECT;
		578	package AE::Log::COLLECT;
516		579
517	package AnyEvent::Log::Ctx;	580	package AnyEvent::Log::Ctx;
518		581
519	# 0 1 2 3 4	582	# 0 1 2 3 4
520	# [$title, $level, %$parents, &$logcb, &$fmtcb]	583	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
521		584
522	=item $ctx = new AnyEvent::Log::Ctx methodname => param...	585	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
523		586
524	This is a convenience constructor that makes it simpler to construct	587	This is a convenience constructor that makes it simpler to construct
525	anonymous logging contexts.	588	anonymous logging contexts.
…		…
528	name as the key with the value as parameter, unless the value is an	591	name as the key with the value as parameter, unless the value is an
529	arrayref, in which case it calls the method with the contents of the	592	arrayref, in which case it calls the method with the contents of the
530	array. The methods are called in the same order as specified.	593	array. The methods are called in the same order as specified.
531		594
532	Example: create a new logging context and set both the default logging	595	Example: create a new logging context and set both the default logging
533	level, some parent contexts and a logging callback.	596	level, some slave contexts and a logging callback.
534		597
535	$ctx = new AnyEvent::Log::Ctx	598	$ctx = new AnyEvent::Log::Ctx
536	title => "dubious messages",	599	title => "dubious messages",
537	level => "error",	600	level => "error",
538	log_cb => sub { print STDOUT shift; 0 },	601	log_cb => sub { print STDOUT shift; 0 },
539	parents => [$ctx1, $ctx, $ctx2],	602	slaves => [$ctx1, $ctx, $ctx2],
540	;	603	;
541		604
542	=back	605	=back
543		606
544	=cut	607	=cut
…		…
657	AnyEvent::Log::_reassess;	720	AnyEvent::Log::_reassess;
658	}	721	}
659		722
660	=back	723	=back
661		724
662	=head3 PARENT CONTEXTS	725	=head3 SLAVE CONTEXTS
663		726
664	The following methods attach and detach another logging context to a	727	The following methods attach and detach another logging context to a
665	logging context.	728	logging context.
666		729
667	Log messages are propagated to all parent contexts, unless the logging	730	Log messages are propagated to all slave contexts, unless the logging
668	callback consumes the message.	731	callback consumes the message.
669		732
670	=over 4	733	=over 4
671		734
672	=item $ctx->attach ($ctx2[, $ctx3...])	735	=item $ctx->attach ($ctx2[, $ctx3...])
673		736
674	Attaches the given contexts as parents to this context. It is not an error	737	Attaches the given contexts as slaves to this context. It is not an error
675	to add a context twice (the second add will be ignored).	738	to add a context twice (the second add will be ignored).
676		739
677	A context can be specified either as package name or as a context object.	740	A context can be specified either as package name or as a context object.
678		741
679	=item $ctx->detach ($ctx2[, $ctx3...])	742	=item $ctx->detach ($ctx2[, $ctx3...])
680		743
681	Removes the given parents from this context - it's not an error to attempt	744	Removes the given slaves from this context - it's not an error to attempt
682	to remove a context that hasn't been added.	745	to remove a context that hasn't been added.
683		746
684	A context can be specified either as package name or as a context object.	747	A context can be specified either as package name or as a context object.
685		748
686	=item $ctx->parents ($ctx2[, $ctx3...])	749	=item $ctx->slaves ($ctx2[, $ctx3...])
687		750
688	Replaces all parents attached to this context by the ones given.	751	Replaces all slaves attached to this context by the ones given.
689		752
690	=cut	753	=cut
691		754
692	sub attach {	755	sub attach {
693	my $ctx = shift;	756	my $ctx = shift;
…		…
701		764
702	delete $ctx->[2]{$_+0}	765	delete $ctx->[2]{$_+0}
703	for map { AnyEvent::Log::ctx $_ } @_;	766	for map { AnyEvent::Log::ctx $_ } @_;
704	}	767	}
705		768
706	sub parents {	769	sub slaves {
707	undef $_[0][2];	770	undef $_[0][2];
708	&attach;	771	&attach;
709	}	772	}
710		773
711	=back	774	=back
712		775
713	=head3 MESSAGE LOGGING	776	=head3 LOG TARGETS
714		777
715	The following methods configure how the logging context actually does	778	The following methods configure how the logging context actually does
716	the logging (which consists of formatting the message and printing it or	779	the logging (which consists of formatting the message and printing it or
717	whatever it wants to do with it) and also allows you to log messages	780	whatever it wants to do with it).
718	directly to a context, without going via your package context.
719		781
720	=over 4	782	=over 4
721		783
722	=item $ctx->log_cb ($cb->($str))	784	=item $ctx->log_cb ($cb->($str)
723		785
724	Replaces the logging callback on the context (C<undef> disables the	786	Replaces the logging callback on the context (C<undef> disables the
725	logging callback).	787	logging callback).
726		788
727	The logging callback is responsible for handling formatted log messages	789	The logging callback is responsible for handling formatted log messages
728	(see C<fmt_cb> below) - normally simple text strings that end with a	790	(see C<fmt_cb> below) - normally simple text strings that end with a
729	newline (and are possibly multiline themselves).	791	newline (and are possibly multiline themselves).
730		792
731	It also has to return true iff it has consumed the log message, and false	793	It also has to return true iff it has consumed the log message, and false
732	if it hasn't. Consuming a message means that it will not be sent to any	794	if it hasn't. Consuming a message means that it will not be sent to any
733	parent context. When in doubt, return C<0> from your logging callback.	795	slave context. When in doubt, return C<0> from your logging callback.
734		796
735	Example: a very simple logging callback, simply dump the message to STDOUT	797	Example: a very simple logging callback, simply dump the message to STDOUT
736	and do not consume it.	798	and do not consume it.
737		799
738	$ctx->log_cb (sub { print STDERR shift; 0 });	800	$ctx->log_cb (sub { print STDERR shift; 0 });
…		…
746	your program.	808	your program.
747		809
748	$ctx->levels ("debug", "trace");	810	$ctx->levels ("debug", "trace");
749	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages	811	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages
750		812
751	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	813	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $orig_ctx, $level, $message))
752		814
753	Replaces the formatting callback on the context (C<undef> restores the	815	Replaces the formatting callback on the context (C<undef> restores the
754	default formatter).	816	default formatter).
755		817
756	The callback is passed the (possibly fractional) timestamp, the original	818	The callback is passed the (possibly fractional) timestamp, the original
757	logging context, the (numeric) logging level and the raw message string and needs to	819	logging context, the (numeric) logging level and the raw message string
758	return a formatted log message. In most cases this will be a string, but	820	and needs to return a formatted log message. In most cases this will be a
759	it could just as well be an array reference that just stores the values.	821	string, but it could just as well be an array reference that just stores
		822	the values.
		823
		824	If, for some reason, you want to use C<caller> to find out more baout the
		825	logger then you should walk up the call stack until you are no longer
		826	inside the C<AnyEvent::Log> package.
760		827
761	Example: format just the raw message, with numeric log level in angle	828	Example: format just the raw message, with numeric log level in angle
762	brackets.	829	brackets.
763		830
764	$ctx->fmt_cb (sub {	831	$ctx->fmt_cb (sub {
…		…
781	"$msg->[3]";	848	"$msg->[3]";
782		849
783	0	850	0
784	});	851	});
785		852
		853	=item $ctx->log_to_warn
		854
		855	Sets the C<log_cb> to simply use C<CORE::warn> to report any messages
		856	(usually this logs to STDERR).
		857
		858	=item $ctx->log_to_file ($path)
		859
		860	Sets the C<log_cb> to log to a file (by appending), unbuffered.
		861
		862	=item $ctx->log_to_path ($path)
		863
		864	Same as C<< ->log_to_file >>, but opens the file for each message. This
		865	is much slower, but allows you to change/move/rename/delete the file at
		866	basically any time.
		867
		868	Needless(?) to say, if you do not want to be bitten by some evil person
		869	calling C<chdir>, the path should be absolute. Doesn't help with
		870	C<chroot>, but hey...
		871
		872	=item $ctx->log_to_syslog ([$facility])
		873
		874	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and
		875	all the others in the obvious way. If specified, then the C<$facility> is
		876	used as the facility (C<user>, C<auth>, C<local0> and so on). The default
		877	facility is C<user>.
		878
		879	Note that this function also sets a C<fmt_cb> - the logging part requires
		880	an array reference with [$level, $str] as input.
		881
786	=cut	882	=cut
787		883
788	sub log_cb {	884	sub log_cb {
789	my ($ctx, $cb) = @_;	885	my ($ctx, $cb) = @_;
790		886
…		…
795	my ($ctx, $cb) = @_;	891	my ($ctx, $cb) = @_;
796		892
797	$ctx->[4] = $cb;	893	$ctx->[4] = $cb;
798	}	894	}
799		895
800	=item $ctx->log ($level, $msg[, @params])	896	sub log_to_warn {
		897	my ($ctx, $path) = @_;
801		898
802	Same as C<AnyEvent::Log::log>, but uses the given context as log context.	899	$ctx->log_cb (sub {
		900	warn shift;
		901	0
		902	});
		903	}
803		904
804	=item $logger = $ctx->logger ($level[, \$enabled])	905	sub log_to_file {
805		906	my ($ctx, $path) = @_;
806	Same as C<AnyEvent::Log::logger>, but uses the given context as log
807	context.
808
809	=cut
810
811	*log = \&AnyEvent::Log::_log;
812	*logger = \&AnyEvent::Log::_logger;
813
814	1;
815
816	=back
817
818	=head1 EXAMPLES
819
820	This section shows some common configurations.
821
822	=over 4
823
824	=item Setting the global logging level.
825
826	Either put PERL_ANYEVENT_VERBOSE=<number> into your environment before
827	running your program, or modify the log level of the root context:
828
829	PERL_ANYEVENT_VERBOSE=5 ./myprog
830
831	$AnyEvent::Log::Root->level ("warn");
832
833	=item Append all messages to a file instead of sending them to STDERR.
834
835	This is affected by the global logging level.
836		907
837	open my $fh, ">>", $path	908	open my $fh, ">>", $path
838	or die "$path: $!";	909	or die "$path: $!";
839		910
840	$AnyEvent::Log::Default->log_cb (sub {	911	$ctx->log_cb (sub {
841	syswrite $fh, shift;	912	syswrite $fh, shift;
842	0	913	0
843	});	914	});
		915	}
		916
		917	sub log_to_path {
		918	my ($ctx, $path) = @_;
		919
		920	$ctx->log_cb (sub {
		921	open my $fh, ">>", $path
		922	or die "$path: $!";
		923
		924	syswrite $fh, shift;
		925	0
		926	});
		927	}
		928
		929	sub log_to_syslog {
		930	my ($ctx, $facility) = @_;
		931
		932	require Sys::Syslog;
		933
		934	$ctx->fmt_cb (sub {
		935	my $str = $_[3];
		936	$str =~ s/\n(?=.)/\n+ /g;
		937
		938	[$_[2], "($_[1][0]) $str"]
		939	});
		940
		941	$facility \|\|= "user";
		942
		943	$ctx->log_cb (sub {
		944	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;
		945
		946	Sys::Syslog::syslog ("$facility\|" . ($lvl - 1), $_)
		947	for split /\n/, $_[0][1];
		948
		949	0
		950	});
		951	}
		952
		953	=back
		954
		955	=head3 MESSAGE LOGGING
		956
		957	These methods allow you to log messages directly to a context, without
		958	going via your package context.
		959
		960	=over 4
		961
		962	=item $ctx->log ($level, $msg[, @params])
		963
		964	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
		965
		966	=item $logger = $ctx->logger ($level[, \$enabled])
		967
		968	Same as C<AnyEvent::Log::logger>, but uses the given context as log
		969	context.
		970
		971	=cut
		972
		973	*log = \&AnyEvent::Log::_log;
		974	*logger = \&AnyEvent::Log::_logger;
		975
		976	=back
		977
		978	=cut
		979
		980	package AnyEvent::Log;
		981
		982	=head1 CONFIGURATION VIA $ENV{PERL_ANYEVENT_LOG}
		983
		984	Logging can also be configured by setting the environment variable
		985	C<PERL_ANYEVENT_LOG> (or C<AE_LOG>).
		986
		987	The value consists of one or more logging context specifications separated
		988	by C<:> or whitespace. Each logging specification in turn starts with a
		989	context name, followed by C<=>, followed by zero or more comma-separated
		990	configuration directives, here are some examples:
		991
		992	# set default logging level
		993	filter=warn
		994
		995	# log to file instead of to stderr
		996	log=file=/tmp/mylog
		997
		998	# log to file in addition to stderr
		999	log=+%file:%file=file=/tmp/mylog
		1000
		1001	# enable debug log messages, log warnings and above to syslog
		1002	filter=debug:log=+%warnings:%warnings=warn,syslog=LOG_LOCAL0
		1003
		1004	# log trace messages (only) from AnyEvent::Debug to file
		1005	AnyEvent::Debug=+%trace:%trace=only,trace,file=/tmp/tracelog
		1006
		1007	A context name in the log specification can be any of the following:
		1008
		1009	=over 4
		1010
		1011	=item C<collect>, C<filter>, C<log>
		1012
		1013	Correspond to the three predefined C<$AnyEvent::Log::COLLECT>,
		1014	C<AnyEvent::Log::FILTER> and C<$AnyEvent::Log::LOG> contexts.
		1015
		1016	=item C<%name>
		1017
		1018	Context names starting with a C<%> are anonymous contexts created when the
		1019	name is first mentioned. The difference to package contexts is that by
		1020	default they have no attached slaves.
		1021
		1022	=item a perl package name
		1023
		1024	Any other string references the logging context associated with the given
		1025	Perl C<package>. In the unlikely case where you want to specify a package
		1026	context that matches on of the other context name forms, you can add a
		1027	C<::> to the package name to force interpretation as a package.
		1028
		1029	=back
		1030
		1031	The configuration specifications can be any number of the following:
		1032
		1033	=over 4
		1034
		1035	=item C<stderr>
		1036
		1037	Configures the context to use Perl's C<warn> function (which typically
		1038	logs to C<STDERR>). Works like C<log_to_warn>.
		1039
		1040	=item C<file=>I<path>
		1041
		1042	Configures the context to log to a file with the given path. Works like
		1043	C<log_to_file>.
		1044
		1045	=item C<path=>I<path>
		1046
		1047	Configures the context to log to a file with the given path. Works like
		1048	C<log_to_path>.
		1049
		1050	=item C<syslog> or C<syslog=>I<expr>
		1051
		1052	Configures the context to log to syslog. If I<expr> is given, then it is
		1053	evaluated in the L<Sys::Syslog> package, so you could use:
		1054
		1055	log=syslog=LOG_LOCAL0
		1056
		1057	=item C<nolog>
		1058
		1059	Configures the context to not log anything by itself, which is the
		1060	default. Same as C<< $ctx->log_cb (undef) >>.
		1061
		1062	=item C<0> or C<off>
		1063
		1064	Sets the logging level of the context ot C<0>, i.e. all messages will be
		1065	filtered out.
		1066
		1067	=item C<all>
		1068
		1069	Enables all logging levels, i.e. filtering will effectively be switched
		1070	off (the default).
		1071
		1072	=item C<only>
		1073
		1074	Disables all logging levels, and changes the interpretation of following
		1075	level specifications to enable the specified level only.
		1076
		1077	Example: only enable debug messages for a context.
		1078
		1079	context=only,debug
		1080
		1081	=item C<except>
		1082
		1083	Enables all logging levels, and changes the interpretation of following
		1084	level specifications to disable that level. Rarely used.
		1085
		1086	Example: enable all logging levels except fatal and trace (this is rather
		1087	nonsensical).
		1088
		1089	filter=exept,fatal,trace
		1090
		1091	=item C<level>
		1092
		1093	Enables all logging levels, and changes the interpretation of following
		1094	level specifications to be "that level or any higher priority
		1095	message". This is the default.
		1096
		1097	Example: log anything at or above warn level.
		1098
		1099	filter=warn
		1100
		1101	# or, more verbose
		1102	filter=only,level,warn
		1103
		1104	=item C<1>..C<9> or a logging level name (C<error>, C<debug> etc.)
		1105
		1106	A numeric loglevel or the name of a loglevel will be interpreted according
		1107	to the most recent C<only>, C<except> or C<level> directive. By default,
		1108	specifying a logging level enables that and any higher priority messages.
		1109
		1110	=item C<+>I<context>
		1111
		1112	Attaches the named context as slave to the context.
		1113
		1114	=item C<+>
		1115
		1116	A line C<+> detaches all contexts, i.e. clears the slave list from the
		1117	context. Anonymous (C<%name>) contexts have no attached slaves by default,
		1118	but package contexts have the parent context as slave by default.
		1119
		1120	Example: log messages from My::Module to a file, do not send them to the
		1121	default log collector.
		1122
		1123	My::Module=+,file=/tmp/mymodulelog
		1124
		1125	=back
		1126
		1127	Any character can be escaped by prefixing it with a C<\> (backslash), as
		1128	usual, so to log to a file containing a comma, colon, backslash and some
		1129	spaces in the filename, you would do this:
		1130
		1131	PERL_ANYEVENT_LOG='log=file=/some\ \:file\ with\,\ \\-escapes'
		1132
		1133	Since whitespace (which includes newlines) is allowed, it is fine to
		1134	specify multiple lines in C<PERL_ANYEVENT_LOG>, e.g.:
		1135
		1136	PERL_ANYEVENT_LOG="
		1137	filter=warn
		1138	AnyEvent::Debug=+%trace
		1139	%trace=only,trace,+log
		1140	" myprog
		1141
		1142	Also, in the unlikely case when you want to concatenate specifications,
		1143	use whitespace as separator, as C<::> will be interpreted as part of a
		1144	module name, an empty spec with two separators:
		1145
		1146	PERL_ANYEVENT_LOG="$PERL_ANYEVENT_LOG MyMod=debug"
		1147
		1148	=cut
		1149
		1150	for (my $spec = $ENV{PERL_ANYEVENT_LOG}) {
		1151	my %anon;
		1152
		1153	my $pkg = sub {
		1154	$_[0] eq "log" ? $LOG
		1155	: $_[0] eq "filter" ? $FILTER
		1156	: $_[0] eq "collect" ? $COLLECT
		1157	: $_[0] =~ /^%(.+)$/ ? ($anon{$1} \|\|= ctx undef)
		1158	: $_[0] =~ /^(.*?)(?:::)?$/ ? ctx "$1" # egad :/
		1159	: die # never reached?
		1160	};
		1161
		1162	/\G[[:space:]]+/gc; # skip initial whitespace
		1163
		1164	while (/\G((?:[^:=[:space:]]+\|::\|\\.)+)=/gc) {
		1165	my $ctx = $pkg->($1);
		1166	my $level = "level";
		1167
		1168	while (/\G((?:[^,:[:space:]]+\|::\|\\.)+)/gc) {
		1169	for ("$1") {
		1170	if ($_ eq "stderr" ) { $ctx->log_to_warn;
		1171	} elsif (/^file=(.+)/ ) { $ctx->log_to_file ("$1");
		1172	} elsif (/^path=(.+)/ ) { $ctx->log_to_path ("$1");
		1173	} elsif (/syslog(?:=(.*))?/ ) { require Sys::Syslog; $ctx->log_to_syslog ($1);
		1174	} elsif ($_ eq "nolog" ) { $ctx->log_cb (undef);
		1175	} elsif (/^\+(.+)$/ ) { $ctx->attach ($pkg->("$1"));
		1176	} elsif ($_ eq "+" ) { $ctx->slaves;
		1177	} elsif ($_ eq "off" or $_ eq "0") { $ctx->level (0);
		1178	} elsif ($_ eq "all" ) { $ctx->level ("all");
		1179	} elsif ($_ eq "level" ) { $ctx->level ("all"); $level = "level";
		1180	} elsif ($_ eq "only" ) { $ctx->level ("off"); $level = "enable";
		1181	} elsif ($_ eq "except" ) { $ctx->level ("all"); $level = "disable";
		1182	} elsif (/^\d$/ ) { $ctx->$level ($_);
		1183	} elsif (exists $STR2LEVEL{$_} ) { $ctx->$level ($_);
		1184	} else { die "PERL_ANYEVENT_LOG ($spec): parse error at '$_'\n";
		1185	}
		1186	}
		1187
		1188	/\G,/gc or last;
		1189	}
		1190
		1191	/\G[:[:space:]]+/gc or last;
		1192	}
		1193
		1194	/\G[[:space:]]+/gc; # skip trailing whitespace
		1195
		1196	if (/\G(.+)/g) {
		1197	die "PERL_ANYEVENT_LOG ($spec): parse error at '$1'\n";
		1198	}
		1199	}
		1200
		1201	1;
		1202
		1203	=head1 EXAMPLES
		1204
		1205	This section shows some common configurations, both as code, and as
		1206	C<PERL_ANYEVENT_LOG> string.
		1207
		1208	=over 4
		1209
		1210	=item Setting the global logging level.
		1211
		1212	Either put C<PERL_ANYEVENT_VERBOSE=><number> into your environment before
		1213	running your program, use C<PERL_ANYEVENT_LOG> or modify the log level of
		1214	the root context at runtime:
		1215
		1216	PERL_ANYEVENT_VERBOSE=5 ./myprog
		1217
		1218	PERL_ANYEVENT_LOG=log=warn
		1219
		1220	$AnyEvent::Log::FILTER->level ("warn");
		1221
		1222	=item Append all messages to a file instead of sending them to STDERR.
		1223
		1224	This is affected by the global logging level.
		1225
		1226	$AnyEvent::Log::LOG->log_to_file ($path);
		1227
		1228	PERL_ANYEVENT_LOG=log=file=/some/path
844		1229
845	=item Write all messages with priority C<error> and higher to a file.	1230	=item Write all messages with priority C<error> and higher to a file.
846		1231
847	This writes them only when the global logging level allows it, because	1232	This writes them only when the global logging level allows it, because
848	it is attached to the default context which is invoked I<after> global	1233	it is attached to the default context which is invoked I<after> global
849	filtering.	1234	filtering.
850		1235
851	open my $fh, ">>", $path	1236	$AnyEvent::Log::FILTER->attach
852	or die "$path: $!";	1237	new AnyEvent::Log::Ctx log_to_file => $path);
853		1238
854	$AnyEvent::Log::Default->attach (new AnyEvent::Log::Ctx	1239	PERL_ANYEVENT_LOG=filter=+%filelogger:%filelogger=file=/some/path
855	log_cb => sub { syswrite $fh, shift; 0 });
856		1240
857	This writes them regardless of the global logging level, because it is	1241	This writes them regardless of the global logging level, because it is
858	attached to the toplevel context, which receives all messages I<before>	1242	attached to the toplevel context, which receives all messages I<before>
859	the global filtering.	1243	the global filtering.
860		1244
861	$AnyEvent::Log::Top->attach (new AnyEvent::Log::Ctx	1245	$AnyEvent::Log::COLLECT->attach (
862	log_cb => sub { syswrite $fh, shift; 0 });	1246	new AnyEvent::Log::Ctx log_to_file => $path);
863		1247
		1248	PERL_ANYEVENT_LOG=%filelogger=file=/some/path:collect=+%filelogger
		1249
864	In both cases, messages are still written to STDOUT.	1250	In both cases, messages are still written to STDERR.
865		1251
866	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).	1252	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
867		1253
868	Attach the CyAnyEvent::Log::Default> context to the C<AnyEvent::Debug>	1254	Attach the C<$AnyEvent::Log::LOG> context to the C<AnyEvent::Debug>
869	context and increase the C<AnyEvent::Debug> logging level - this simply
870	circumvents the global filtering for trace messages.	1255	context - this simply circumvents the global filtering for trace messages.
871		1256
872	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;	1257	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
873	$debug->attach ($AnyEvent::Log::Default);	1258	$debug->attach ($AnyEvent::Log::LOG);
874	$debug->levels ("trace"); # not "level"!
875		1259
876	This of course works for any package.	1260	PERL_ANYEVENT_LOG=AnyEvent::Debug=+log
		1261
		1262	This of course works for any package, not just L<AnyEvent::Debug>, but
		1263	assumes the log level for AnyEvent::Debug hasn't been changed from the
		1264	default.
877		1265
878	=back	1266	=back
879		1267
880	=head1 AUTHOR	1268	=head1 AUTHOR
881		1269
882	Marc Lehmann <schmorp@schmorp.de>	1270	Marc Lehmann <schmorp@schmorp.de>
883	http://home.schmorp.de/	1271	http://home.schmorp.de/
884		1272
885	=cut	1273	=cut
		1274

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents): Revision 1.15 by root, Sat Aug 20 02:16:59 2011 UTC vs. Revision 1.41 by root, Thu Sep 1 04:07:18 2011 UTC

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.15 by root, Sat Aug 20 02:16:59 2011 UTC vs.
Revision 1.41 by root, Thu Sep 1 04:07:18 2011 UTC