[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 1.43 by root, Mon Sep 5 07:21:54 2011 UTC

…		…
2		2
3	AnyEvent::Log - simple logging "framework"	3	AnyEvent::Log - simple logging "framework"
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	# simple use	7	Simple uses:
		8
8	use AnyEvent;	9	use AnyEvent;
9		10
10	AE::log debug => "hit my knee";	11	AE::log debug => "hit my knee";
11	AE::log warn => "it's a bit too hot";	12	AE::log warn => "it's a bit too hot";
12	AE::log error => "the flag was false!";	13	AE::log error => "the flag was false!";
13	AE::log fatal => "the bit toggled! run!";	14	AE::log fatal => "the bit toggled! run!"; # never returns
14		15
15	# "complex" use	16	# available log levels in order:
		17	# fatal alert critical error warn note info debug trace
		18
		19	"Complex" uses (for speed sensitive code):
		20
16	use AnyEvent::Log;	21	use AnyEvent::Log;
17		22
18	my $tracer = AnyEvent::Log::logger trace => \$my $trace;	23	my $tracer = AnyEvent::Log::logger trace => \$my $trace;
19		24
20	$tracer->("i am here") if $trace;	25	$tracer->("i am here") if $trace;
21	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;	26	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;
22		27
23	# configuration	28	Configuration (also look at the EXAMPLES section):
24		29
25	# set logging for this package to 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 system unusable, aborts program!
		81	2 alert failure in primary system
		82	3 critical crit failure in backup system
		83	4 error err die non-urgent program errors, a bug
		84	5 warn warning possible problem, not necessarily error
		85	6 note notice unusual conditions
		86	7 info normal messages, no action required
		87	8 debug debugging messages for development
		88	9 trace copious tracing output
		89
		90	As you can see, some logging levels have multiple aliases - the first one
		91	is the "official" name, the second one the "syslog" name (if it differs)
		92	and the third one the "perl" name, suggesting (only!) that you log C<die>
		93	messages at C<error> priority. The NOTE column tries to provide some
		94	rationale on how to chose a logging level.
		95
		96	As a rough guideline, levels 1..3 are primarily meant for users of
		97	the program (admins, staff), and are the only logged to STDERR by
		98	default. Levels 4..6 are meant for users and developers alike, while
		99	levels 7..9 are usually meant for developers.
		100
		101	You can normally only log a single message at highest priority level
		102	(C<1>, C<fatal>), because logging a fatal message will also quit the
		103	program - so use it sparingly :)
		104
		105	Some methods also offer some extra levels, such as C<0>, C<off>, C<none>
		106	or C<all> - these are only valid in the methods they are documented for.
64		107
65	=head1 LOGGING FUNCTIONS	108	=head1 LOGGING FUNCTIONS
66		109
67	These functions allow you to log messages. They always use the caller's	110	These functions allow you to log messages. They always use the caller's
68	package as a "logging module/source". Also, the main logging function is	111	package as a "logging context". Also, the main logging function C<log> is
69	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is	112	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is
70	loaded.	113	loaded.
71		114
72	=over 4	115	=over 4
73		116
…		…
77		120
78	use Carp ();	121	use Carp ();
79	use POSIX ();	122	use POSIX ();
80		123
81	use AnyEvent (); BEGIN { AnyEvent::common_sense }	124	use AnyEvent (); BEGIN { AnyEvent::common_sense }
82	use AnyEvent::Util ();	125	#use AnyEvent::Util (); need to load this in a delayed fashion, as it uses AE::log
83		126
84	our $VERSION = $AnyEvent::VERSION;	127	our $VERSION = $AnyEvent::VERSION;
		128
		129	our ($COLLECT, $FILTER, $LOG);
85		130
86	our ($now_int, $now_str1, $now_str2);	131	our ($now_int, $now_str1, $now_str2);
87		132
88	# Format Time, not public - yet?	133	# Format Time, not public - yet?
89	sub ft($) {	134	sub ft($) {
…		…
94	if $now_int != $i;	139	if $now_int != $i;
95		140
96	"$now_str1$f$now_str2"	141	"$now_str1$f$now_str2"
97	}	142	}
98		143
99	our %CTX; # all logging contexts	144	our %CTX; # all package contexts
100		145
101	# creates a default package context object for the given package	146	# creates a default package context object for the given package
102	sub _pkg_ctx($) {	147	sub _pkg_ctx($) {
103	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";	148	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";
104		149
105	# link "parent" package	150	# link "parent" package
106	my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "AE::Log::Top";	151	my $parent = $_[0] =~ /^(.+)::/
		152	? $CTX{$1} \|\|= &_pkg_ctx ("$1")
		153	: $COLLECT;
107		154
108	$pkg = $CTX{$pkg} \|\|= &_pkg_ctx ($pkg);
109	$ctx->[2]{$pkg+0} = $pkg;	155	$ctx->[2]{$parent+0} = $parent;
110		156
111	$ctx	157	$ctx
112	}	158	}
113		159
114	=item AnyEvent::Log::log $level, $msg[, @args]	160	=item AnyEvent::Log::log $level, $msg[, @args]
115		161
116	Requests logging of the given C<$msg> with the given log level (1..9).	162	Requests logging of the given C<$msg> with the given log level, and
117	You can also use the following strings as log level: C<fatal> (1),	163	returns true if the message was logged I<somewhere>.
118	C<alert> (2), C<critical> (3), C<error> (4), C<warn> (5), C<note> (6),
119	C<info> (7), C<debug> (8), C<trace> (9).
120		164
121	For C<fatal> log levels, the program will abort.	165	For loglevel C<fatal>, the program will abort.
122		166
123	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the	167	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the
124	C<$msg> is interpreted as an sprintf format string.	168	C<$msg> is interpreted as an sprintf format string.
125		169
126	The C<$msg> should not end with C<\n>, but may if that is convenient for	170	The C<$msg> should not end with C<\n>, but may if that is convenient for
…		…
130	supposed to return the message. It will be called only then the message	174	supposed to return the message. It will be called only then the message
131	actually gets logged, which is useful if it is costly to create the	175	actually gets logged, which is useful if it is costly to create the
132	message in the first place.	176	message in the first place.
133		177
134	Whether the given message will be logged depends on the maximum log level	178	Whether the given message will be logged depends on the maximum log level
135	and the caller's package.	179	and the caller's package. The return value can be used to ensure that
		180	messages or not "lost" - for example, when L<AnyEvent::Debug> detects a
		181	runtime error it tries to log it at C<die> level, but if that message is
		182	lost it simply uses warn.
136		183
137	Note that you can (and should) call this function as C<AnyEvent::log> or	184	Note that you can (and should) call this function as C<AnyEvent::log> or
138	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't	185	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't
139	need any additional functionality), as those functions will load the	186	need any additional functionality), as those functions will load the
140	logging module on demand only. They are also much shorter to write.	187	logging module on demand only. They are also much shorter to write.
…		…
157		204
158	=cut	205	=cut
159		206
160	# also allow syslog equivalent names	207	# also allow syslog equivalent names
161	our %STR2LEVEL = (	208	our %STR2LEVEL = (
162	fatal => 1, emerg => 1,	209	fatal => 1, emerg => 1, exit => 1,
163	alert => 2,	210	alert => 2,
164	critical => 3, crit => 3,	211	critical => 3, crit => 3,
165	error => 4, err => 4,	212	error => 4, err => 4, die => 4,
166	warn => 5, warning => 5,	213	warn => 5, warning => 5,
167	note => 6, notice => 6,	214	note => 6, notice => 6,
168	info => 7,	215	info => 7,
169	debug => 8,	216	debug => 8,
170	trace => 9,	217	trace => 9,
171	);	218	);
172		219
173	sub now () { time }	220	our $TIME_EXACT;
		221
		222	sub exact_time($) {
		223	$TIME_EXACT = shift;
		224	*_ts = $AnyEvent::MODEL
		225	? $TIME_EXACT ? \&AE::now : \&AE::time
		226	: sub () { $TIME_EXACT ? do { require Time::HiRes; Time::HiRes::time () } : time };
		227	}
		228
		229	BEGIN {
		230	exact_time 0;
		231	}
174		232
175	AnyEvent::post_detect {	233	AnyEvent::post_detect {
176	*now = \&AE::now;	234	exact_time $TIME_EXACT;
177	};	235	};
178		236
179	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);	237	our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace);
180		238
181	# time, ctx, level, msg	239	# time, ctx, level, msg
…		…
191	}	249	}
192		250
193	join "", @res	251	join "", @res
194	}	252	}
195		253
		254	sub fatal_exit() {
		255	exit 1;
		256	}
		257
196	sub _log {	258	sub _log {
197	my ($ctx, $level, $format, @args) = @_;	259	my ($ctx, $level, $format, @args) = @_;
198		260
199	$level = $level > 0 && $level <= 9	261	$level = $level > 0 && $level <= 9
200	? $level+0	262	? $level+0
201	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";	263	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";
202		264
203	my $mask = 1 << $level;	265	my $mask = 1 << $level;
204		266
205	my (%seen, @ctx, $now, $fmt);	267	my ($success, %seen, @ctx, $now, $fmt);
206		268
207	do	269	do
208	{	270	{
209	# skip if masked	271	# skip if masked
210	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {	272	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {
…		…
214	# now get raw message, unless we have it already	276	# now get raw message, unless we have it already
215	unless ($now) {	277	unless ($now) {
216	$format = $format->() if ref $format;	278	$format = $format->() if ref $format;
217	$format = sprintf $format, @args if @args;	279	$format = sprintf $format, @args if @args;
218	$format =~ s/\n$//;	280	$format =~ s/\n$//;
219	$now = AE::now;	281	$now = _ts;
220	};	282	};
221		283
222	# format msg	284	# format msg
223	my $str = $ctx->[4]	285	my $str = $ctx->[4]
224	? $ctx->[4]($now, $_[0], $level, $format)	286	? $ctx->[4]($now, $_[0], $level, $format)
225	: $fmt \|\|= _format $now, $_[0], $level, $format;	287	: ($fmt \|\|= _format $now, $_[0], $level, $format);
226		288
		289	$success = 1;
		290
227	$ctx->[3]($str);	291	$ctx->[3]($str)
		292	or push @ctx, values %{ $ctx->[2] }; # not consumed - propagate
		293	} else {
		294	push @ctx, values %{ $ctx->[2] }; # not masked - propagate
228	}	295	}
229
230	# not masked, not consumed - propagate to parent contexts
231	push @ctx, values %{ $ctx->[2] };
232	}	296	}
233	}	297	}
234	while $ctx = pop @ctx;	298	while $ctx = pop @ctx;
235		299
236	exit 1 if $level <= 1;	300	fatal_exit if $level <= 1;
		301
		302	$success
237	}	303	}
238		304
239	sub log($$;@) {	305	sub log($$;@) {
240	_log	306	_log
241	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	307	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
242	@_;	308	@_;
243	}	309	}
244		310
245	AnyEvent::log = AE::log = \&log;
246
247	=item $logger = AnyEvent::Log::logger $level[, \$enabled]	311	=item $logger = AnyEvent::Log::logger $level[, \$enabled]
248		312
249	Creates a code reference that, when called, acts as if the	313	Creates a code reference that, when called, acts as if the
250	C<AnyEvent::Log::log> function was called at this point with the givne	314	C<AnyEvent::Log::log> function was called at this point with the given
251	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with	315	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with
252	the C<AnyEvent::Log::log> function:	316	the C<AnyEvent::Log::log> function:
253		317
254	my $debug_log = AnyEvent::Log::logger "debug";	318	my $debug_log = AnyEvent::Log::logger "debug";
255		319
…		…
280	# and later in your program	344	# and later in your program
281	$debug_log->("yo, stuff here") if $debug;	345	$debug_log->("yo, stuff here") if $debug;
282		346
283	$debug and $debug_log->("123");	347	$debug and $debug_log->("123");
284		348
285	Note: currently the enabled var is always true - that will be fixed in a
286	future version :)
287
288	=cut	349	=cut
289		350
290	our %LOGGER;	351	our %LOGGER;
291		352
292	# re-assess logging status for all loggers	353	# re-assess logging status for all loggers
293	sub _reassess {	354	sub _reassess {
		355	local $SIG{__DIE__};
		356	my $die = sub { die };
		357
294	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {	358	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {
295	my ($ctx, $level, $renabled) = @$_;	359	my ($ctx, $level, $renabled) = @$_;
296		360
297	# to detect whether a message would be logged, we # actually	361	# 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	362	# try to log one and die. this isn't fast, but we can be
299	# sure that the logging decision is correct :)	363	# sure that the logging decision is correct :)
300		364
301	$$renabled = !eval {	365	$$renabled = !eval {
302	local $SIG{__DIE__};
303
304	_log $ctx, $level, sub { die };	366	_log $ctx, $level, $die;
305		367
306	1	368	1
307	};	369	};
308
309	$$renabled = 1; # TODO
310	}	370	}
311	}	371	}
312		372
313	sub _logger {	373	sub _logger {
314	my ($ctx, $level, $renabled) = @_;	374	my ($ctx, $level, $renabled) = @_;
…		…
319		379
320	$LOGGER{$logger+0} = $logger;	380	$LOGGER{$logger+0} = $logger;
321		381
322	_reassess $logger+0;	382	_reassess $logger+0;
323		383
		384	require AnyEvent::Util unless $AnyEvent::Util::VERSION;
324	my $guard = AnyEvent::Util::guard {	385	my $guard = AnyEvent::Util::guard (sub {
325	# "clean up"	386	# "clean up"
326	delete $LOGGER{$logger+0};	387	delete $LOGGER{$logger+0};
327	};	388	});
328		389
329	sub {	390	sub {
330	$guard if 0; # keep guard alive, but don't cause runtime overhead	391	$guard if 0; # keep guard alive, but don't cause runtime overhead
331		392
332	_log $ctx, $level, @_	393	_log $ctx, $level, @_
…		…
337	sub logger($;$) {	398	sub logger($;$) {
338	_logger	399	_logger
339	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	400	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
340	@_	401	@_
341	}	402	}
		403
		404	=item AnyEvent::Log::exact_time $on
		405
		406	By default, C<AnyEvent::Log> will use C<AE::now>, i.e. the cached
		407	eventloop time, for the log timestamps. After calling this function with a
		408	true value it will instead resort to C<AE::time>, i.e. fetch the current
		409	time on each log message. This only makes a difference for event loops
		410	that actually cache the time (such as L<EV> or L<AnyEvent::Loop>).
		411
		412	This setting can be changed at any time by calling this function.
		413
		414	Since C<AnyEvent::Log> has to work even before the L<AnyEvent> has been
		415	initialised, this switch will also decide whether to use C<CORE::time> or
		416	C<Time::HiRes::time> when logging a message before L<AnyEvent> becomes
		417	available.
342		418
343	=back	419	=back
344		420
345	=head1 LOGGING CONTEXTS	421	=head1 LOGGING CONTEXTS
346		422
…		…
359	timestamp, context, level and string message and formats it in the way	435	timestamp, context, level and string message and formats it in the way
360	it should be logged) and a logging callback (which is responsible for	436	it should be logged) and a logging callback (which is responsible for
361	actually logging the formatted message and telling C<AnyEvent::Log>	437	actually logging the formatted message and telling C<AnyEvent::Log>
362	whether it has consumed the message, or whether it should be propagated).	438	whether it has consumed the message, or whether it should be propagated).
363		439
364	For propagation, a context can have any number of attached I<parent	440	For propagation, a context can have any number of attached I<slave
365	contexts>. Any message that is neither masked by the logging mask nor	441	contexts>. Any message that is neither masked by the logging mask nor
366	masked by the logging callback returning true will be passed to all parent	442	masked by the logging callback returning true will be passed to all slave
367	contexts.	443	contexts.
368		444
369	Each call to a logging function will log the message at most once per	445	Each call to a logging function will log the message at most once per
370	context, so it does not matter (much) if there are cycles or if the	446	context, so it does not matter (much) if there are cycles or if the
371	message can arrive at the same context via multiple paths.	447	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	451	By default, all logging contexts have an full set of log levels ("all"), a
376	disabled logging callback and the default formatting callback.	452	disabled logging callback and the default formatting callback.
377		453
378	Package contexts have the package name as logging title by default.	454	Package contexts have the package name as logging title by default.
379		455
380	They have exactly one parent - the context of the "parent" package. The	456	They have exactly one slave - the context of the "parent" package. The
381	parent package is simply defined to be the package name without the last	457	parent package is simply defined to be the package name without the last
382	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,	458	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
383	and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the	459	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	460	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	461	package name in Perl is C<main>, the default slave of any top-level
386	C<AnyEvent::Log::Top>.	462	package context is C<$AnyEvent::Log::COLLECT>.
387		463
388	Since perl packages form only an approximate hierarchy, this parent	464	Since perl packages form only an approximate hierarchy, this slave
389	context can of course be removed.	465	context can of course be removed.
390		466
391	All other (anonymous) contexts have no parents and an empty title by	467	All other (anonymous) contexts have no slaves and an empty title by
392	default.	468	default.
393		469
394	When the module is loaded it creates the default context called	470	When the module is loaded it creates the C<$AnyEvent::Log::LOG> logging
395	C<AnyEvent::Log::Default> (also stored in C<$AnyEvent::Log::Default>),	471	context that simply logs everything via C<warn>, without propagating
396	which simply logs everything via C<warn> and doesn't propagate anything
397	anywhere by default. The purpose of the default context is to provide	472	anything anywhere by default. The purpose of this context is to provide
398	a convenient place to override the global logging target or to attach	473	a convenient place to override the global logging target or to attach
399	additional log targets. It's not meant for filtering.	474	additional log targets. It's not meant for filtering.
400		475
401	It then creates the root context called C<AnyEvent::Log::Root> (also	476	It then creates the C<$AnyEvent::Log::FILTER> context whose
402	stored in C<$AnyEvent::Log::Root>) and sets its log level set to all	477	purpose is to suppress all messages with priority higher
403	levels up to the one specified by C<$ENV{PERL_ANYEVENT_VERBOSE}>. It	478	than C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the
404	then attached the default logging context to it. The purpose of the root	479	C<$AnyEvent::Log::LOG> context to it. The purpose of the filter context
405	context is to simply provide filtering according to some global log level.	480	is to simply provide filtering according to some global log level.
406		481
407	Finally it creates the top-level package context called	482	Finally it creates the top-level package context C<$AnyEvent::Log::COLLECT>
408	C<AnyEvent::Log::Top> (also stored in, you might have guessed,	483	and attaches the C<$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	484	leaves it at default config. Its purpose is simply to collect all log
411	system-wide.	485	messages system-wide.
412		486
413	These three special contexts can also be referred to by the	487	The hierarchy is then:
414	package/context names C<AE::Log::Default>, C<AE::Log::Root> and
415	C<AE::Log::Top>.
416		488
		489	any package, eventually -> $COLLECT -> $FILTER -> $LOG
		490
417	The effect of all this is that log messages, by default, wander up	491	The effect of all this is that log messages, by default, wander up to the
418	to the root context where log messages with lower priority then	492	C<$AnyEvent::Log::COLLECT> context where all messages normally end up,
		493	from there to C<$AnyEvent::Log::FILTER> where log messages with lower
419	C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered away and then to the	494	priority then C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered out and then
420	AnyEvent::Log::Default context to be passed to C<warn>.	495	to the C<$AnyEvent::Log::LOG> context to be passed to C<warn>.
421		496
422	Splitting the top level context into three contexts makes it easy to set	497	This makes it easy to set a global logging level (by modifying $FILTER),
423	a global logging level (by modifying the root context), but still allow	498	but still allow other contexts to send, for example, their debug and trace
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	499	messages to the $LOG target despite the global logging level, or to attach
426	log targets that log messages, regardless of the global logging level.	500	additional log targets that log messages, regardless of the global logging
		501	level.
427		502
428	It also makes it easy to replace the default warn-logger by something that	503	It also makes it easy to modify the default warn-logger ($LOG) to
429	logs to a file, or to attach additional logging targets.	504	something that logs to a file, or to attach additional logging targets
		505	(such as loggign to a file) by attaching it to $FILTER.
430		506
431	=head2 CREATING/FINDING/DESTROYING CONTEXTS	507	=head2 CREATING/FINDING/DESTROYING CONTEXTS
432		508
433	=over 4	509	=over 4
434		510
…		…
456	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"	532	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"
457	}	533	}
458		534
459	=item AnyEvent::Log::reset	535	=item AnyEvent::Log::reset
460		536
461	Resets all package contexts contexts and recreates the default hierarchy	537	Resets all package contexts and recreates the default hierarchy if
462	if necessary, i.e. resets the logging subsystem to defaults.	538	necessary, i.e. resets the logging subsystem to defaults, as much as
		539	possible. This process keeps references to contexts held by other parts of
		540	the program intact.
463		541
464	This can be used to implement config-file (re-)loading: before loading a	542	This can be used to implement config-file (re-)loading: before loading a
465	configuration, reset all contexts.	543	configuration, reset all contexts.
466		544
467	Note that this currently destroys all logger callbacks - bug me if you
468	need this fixed :)
469
470	=cut	545	=cut
		546
		547	our $ORIG_VERBOSE = $AnyEvent::VERBOSE;
		548	$AnyEvent::VERBOSE = 9;
471		549
472	sub reset {	550	sub reset {
473	# hard to kill complex data structures	551	# hard to kill complex data structures
474	# we recreate all package loggers and reset the hierarchy	552	# we "recreate" all package loggers and reset the hierarchy
475	while (my ($k, $v) = each %CTX) {	553	while (my ($k, $v) = each %CTX) {
476	@$v = ($k, (1 << 10) - 1 - 1, { });	554	@$v = ($k, (1 << 10) - 1 - 1, { });
477		555
478	my $pkg = $k =~ /^(.+)::/ ? $1 : "AE::Log::Top";	556	$v->attach ($k =~ /^(.+)::/ ? $CTX{$1} : $AnyEvent::Log::COLLECT);
479	$v->attach ($CTX{$pkg});
480	}	557	}
481		558
482	$AnyEvent::Log::Default->parents;	559	@$_ = ($_->[0], (1 << 10) - 1 - 1)
483	$AnyEvent::Log::Default->title ("AnyEvent::Log::Default");	560	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		561
490	$AnyEvent::Log::Root->parents ($AnyEvent::Log::Default);	562	#$LOG->slaves;
491	$AnyEvent::Log::Root->title ("AnyEvent::Log::Root");	563	$LOG->title ('$AnyEvent::Log::LOG');
492	$AnyEvent::Log::Root->level ($AnyEvent::VERBOSE);	564	$LOG->log_to_warn;
493	$CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $AnyEvent::Log::Root;
494		565
495	$AnyEvent::Log::Top->parents ($AnyEvent::Log::Root);	566	$FILTER->slaves ($LOG);
496	$AnyEvent::Log::Top->title ("AnyEvent::Log::Top");	567	$FILTER->title ('$AnyEvent::Log::FILTER');
497	$CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $AnyEvent::Log::Top;	568	$FILTER->level ($ORIG_VERBOSE);
		569
		570	$COLLECT->slaves ($FILTER);
		571	$COLLECT->title ('$AnyEvent::Log::COLLECT');
498		572
499	_reassess;	573	_reassess;
500	}	574	}
501		575
		576	# override AE::log/logger
		577	AnyEvent::log = AE::log = \&log;
		578	AnyEvent::logger = AE::logger = \&logger;
		579
		580	# convert AnyEvent loggers to AnyEvent::Log loggers
		581	$_->[0] = ctx $_->[0] # convert "pkg" to "ctx"
		582	for values %LOGGER;
		583
502	# create the default logger contexts	584	# create the default logger contexts
503	$AnyEvent::Log::Default = ctx undef;	585	$LOG = ctx undef;
504	$AnyEvent::Log::Root = ctx undef;	586	$FILTER = ctx undef;
505	$AnyEvent::Log::Top = ctx undef;	587	$COLLECT = ctx undef;
506		588
507	AnyEvent::Log::reset;	589	AnyEvent::Log::reset;
508		590
509	# hello, CPAN, please catch me	591	# hello, CPAN, please catch me
510	package AnyEvent::Log::Default;
511	package AE::Log::Default;
512	package AnyEvent::Log::Root;
513	package AE::Log::Root;
514	package AnyEvent::Log::Top;	592	package AnyEvent::Log::LOG;
515	package AE::Log::Top;	593	package AE::Log::LOG;
		594	package AnyEvent::Log::FILTER;
		595	package AE::Log::FILTER;
		596	package AnyEvent::Log::COLLECT;
		597	package AE::Log::COLLECT;
516		598
517	package AnyEvent::Log::Ctx;	599	package AnyEvent::Log::Ctx;
518		600
519	# 0 1 2 3 4	601	# 0 1 2 3 4
520	# [$title, $level, %$parents, &$logcb, &$fmtcb]	602	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
521		603
522	=item $ctx = new AnyEvent::Log::Ctx methodname => param...	604	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
523		605
524	This is a convenience constructor that makes it simpler to construct	606	This is a convenience constructor that makes it simpler to construct
525	anonymous logging contexts.	607	anonymous logging contexts.
…		…
528	name as the key with the value as parameter, unless the value is an	610	name as the key with the value as parameter, unless the value is an
529	arrayref, in which case it calls the method with the contents of the	611	arrayref, in which case it calls the method with the contents of the
530	array. The methods are called in the same order as specified.	612	array. The methods are called in the same order as specified.
531		613
532	Example: create a new logging context and set both the default logging	614	Example: create a new logging context and set both the default logging
533	level, some parent contexts and a logging callback.	615	level, some slave contexts and a logging callback.
534		616
535	$ctx = new AnyEvent::Log::Ctx	617	$ctx = new AnyEvent::Log::Ctx
536	title => "dubious messages",	618	title => "dubious messages",
537	level => "error",	619	level => "error",
538	log_cb => sub { print STDOUT shift; 0 },	620	log_cb => sub { print STDOUT shift; 0 },
539	parents => [$ctx1, $ctx, $ctx2],	621	slaves => [$ctx1, $ctx, $ctx2],
540	;	622	;
541		623
542	=back	624	=back
543		625
544	=cut	626	=cut
…		…
657	AnyEvent::Log::_reassess;	739	AnyEvent::Log::_reassess;
658	}	740	}
659		741
660	=back	742	=back
661		743
662	=head3 PARENT CONTEXTS	744	=head3 SLAVE CONTEXTS
663		745
664	The following methods attach and detach another logging context to a	746	The following methods attach and detach another logging context to a
665	logging context.	747	logging context.
666		748
667	Log messages are propagated to all parent contexts, unless the logging	749	Log messages are propagated to all slave contexts, unless the logging
668	callback consumes the message.	750	callback consumes the message.
669		751
670	=over 4	752	=over 4
671		753
672	=item $ctx->attach ($ctx2[, $ctx3...])	754	=item $ctx->attach ($ctx2[, $ctx3...])
673		755
674	Attaches the given contexts as parents to this context. It is not an error	756	Attaches the given contexts as slaves to this context. It is not an error
675	to add a context twice (the second add will be ignored).	757	to add a context twice (the second add will be ignored).
676		758
677	A context can be specified either as package name or as a context object.	759	A context can be specified either as package name or as a context object.
678		760
679	=item $ctx->detach ($ctx2[, $ctx3...])	761	=item $ctx->detach ($ctx2[, $ctx3...])
680		762
681	Removes the given parents from this context - it's not an error to attempt	763	Removes the given slaves from this context - it's not an error to attempt
682	to remove a context that hasn't been added.	764	to remove a context that hasn't been added.
683		765
684	A context can be specified either as package name or as a context object.	766	A context can be specified either as package name or as a context object.
685		767
686	=item $ctx->parents ($ctx2[, $ctx3...])	768	=item $ctx->slaves ($ctx2[, $ctx3...])
687		769
688	Replaces all parents attached to this context by the ones given.	770	Replaces all slaves attached to this context by the ones given.
689		771
690	=cut	772	=cut
691		773
692	sub attach {	774	sub attach {
693	my $ctx = shift;	775	my $ctx = shift;
…		…
701		783
702	delete $ctx->[2]{$_+0}	784	delete $ctx->[2]{$_+0}
703	for map { AnyEvent::Log::ctx $_ } @_;	785	for map { AnyEvent::Log::ctx $_ } @_;
704	}	786	}
705		787
706	sub parents {	788	sub slaves {
707	undef $_[0][2];	789	undef $_[0][2];
708	&attach;	790	&attach;
709	}	791	}
710		792
711	=back	793	=back
712		794
713	=head3 MESSAGE LOGGING	795	=head3 LOG TARGETS
714		796
715	The following methods configure how the logging context actually does	797	The following methods configure how the logging context actually does
716	the logging (which consists of formatting the message and printing it or	798	the logging (which consists of formatting the message and printing it or
717	whatever it wants to do with it) and also allows you to log messages	799	whatever it wants to do with it).
718	directly to a context, without going via your package context.
719		800
720	=over 4	801	=over 4
721		802
722	=item $ctx->log_cb ($cb->($str))	803	=item $ctx->log_cb ($cb->($str)
723		804
724	Replaces the logging callback on the context (C<undef> disables the	805	Replaces the logging callback on the context (C<undef> disables the
725	logging callback).	806	logging callback).
726		807
727	The logging callback is responsible for handling formatted log messages	808	The logging callback is responsible for handling formatted log messages
728	(see C<fmt_cb> below) - normally simple text strings that end with a	809	(see C<fmt_cb> below) - normally simple text strings that end with a
729	newline (and are possibly multiline themselves).	810	newline (and are possibly multiline themselves).
730		811
731	It also has to return true iff it has consumed the log message, and false	812	It also has to return true iff it has consumed the log message, and false
732	if it hasn't. Consuming a message means that it will not be sent to any	813	if it hasn't. Consuming a message means that it will not be sent to any
733	parent context. When in doubt, return C<0> from your logging callback.	814	slave context. When in doubt, return C<0> from your logging callback.
734		815
735	Example: a very simple logging callback, simply dump the message to STDOUT	816	Example: a very simple logging callback, simply dump the message to STDOUT
736	and do not consume it.	817	and do not consume it.
737		818
738	$ctx->log_cb (sub { print STDERR shift; 0 });	819	$ctx->log_cb (sub { print STDERR shift; 0 });
…		…
746	your program.	827	your program.
747		828
748	$ctx->levels ("debug", "trace");	829	$ctx->levels ("debug", "trace");
749	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages	830	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages
750		831
751	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	832	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $orig_ctx, $level, $message))
752		833
753	Replaces the formatting callback on the context (C<undef> restores the	834	Replaces the formatting callback on the context (C<undef> restores the
754	default formatter).	835	default formatter).
755		836
756	The callback is passed the (possibly fractional) timestamp, the original	837	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	838	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	839	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.	840	string, but it could just as well be an array reference that just stores
		841	the values.
		842
		843	If, for some reason, you want to use C<caller> to find out more baout the
		844	logger then you should walk up the call stack until you are no longer
		845	inside the C<AnyEvent::Log> package.
760		846
761	Example: format just the raw message, with numeric log level in angle	847	Example: format just the raw message, with numeric log level in angle
762	brackets.	848	brackets.
763		849
764	$ctx->fmt_cb (sub {	850	$ctx->fmt_cb (sub {
…		…
781	"$msg->[3]";	867	"$msg->[3]";
782		868
783	0	869	0
784	});	870	});
785		871
		872	=item $ctx->log_to_warn
		873
		874	Sets the C<log_cb> to simply use C<CORE::warn> to report any messages
		875	(usually this logs to STDERR).
		876
		877	=item $ctx->log_to_file ($path)
		878
		879	Sets the C<log_cb> to log to a file (by appending), unbuffered.
		880
		881	=item $ctx->log_to_path ($path)
		882
		883	Same as C<< ->log_to_file >>, but opens the file for each message. This
		884	is much slower, but allows you to change/move/rename/delete the file at
		885	basically any time.
		886
		887	Needless(?) to say, if you do not want to be bitten by some evil person
		888	calling C<chdir>, the path should be absolute. Doesn't help with
		889	C<chroot>, but hey...
		890
		891	=item $ctx->log_to_syslog ([$facility])
		892
		893	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and
		894	all the others in the obvious way. If specified, then the C<$facility> is
		895	used as the facility (C<user>, C<auth>, C<local0> and so on). The default
		896	facility is C<user>.
		897
		898	Note that this function also sets a C<fmt_cb> - the logging part requires
		899	an array reference with [$level, $str] as input.
		900
786	=cut	901	=cut
787		902
788	sub log_cb {	903	sub log_cb {
789	my ($ctx, $cb) = @_;	904	my ($ctx, $cb) = @_;
790		905
…		…
795	my ($ctx, $cb) = @_;	910	my ($ctx, $cb) = @_;
796		911
797	$ctx->[4] = $cb;	912	$ctx->[4] = $cb;
798	}	913	}
799		914
800	=item $ctx->log ($level, $msg[, @params])	915	sub log_to_warn {
		916	my ($ctx, $path) = @_;
801		917
802	Same as C<AnyEvent::Log::log>, but uses the given context as log context.	918	$ctx->log_cb (sub {
		919	warn shift;
		920	0
		921	});
		922	}
803		923
804	=item $logger = $ctx->logger ($level[, \$enabled])	924	sub log_to_file {
805		925	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		926
837	open my $fh, ">>", $path	927	open my $fh, ">>", $path
838	or die "$path: $!";	928	or die "$path: $!";
839		929
840	$AnyEvent::Log::Default->log_cb (sub {	930	$ctx->log_cb (sub {
841	syswrite $fh, shift;	931	syswrite $fh, shift;
842	0	932	0
843	});	933	});
		934	}
		935
		936	sub log_to_path {
		937	my ($ctx, $path) = @_;
		938
		939	$ctx->log_cb (sub {
		940	open my $fh, ">>", $path
		941	or die "$path: $!";
		942
		943	syswrite $fh, shift;
		944	0
		945	});
		946	}
		947
		948	sub log_to_syslog {
		949	my ($ctx, $facility) = @_;
		950
		951	require Sys::Syslog;
		952
		953	$ctx->fmt_cb (sub {
		954	my $str = $_[3];
		955	$str =~ s/\n(?=.)/\n+ /g;
		956
		957	[$_[2], "($_[1][0]) $str"]
		958	});
		959
		960	$facility \|\|= "user";
		961
		962	$ctx->log_cb (sub {
		963	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;
		964
		965	Sys::Syslog::syslog ("$facility\|" . ($lvl - 1), $_)
		966	for split /\n/, $_[0][1];
		967
		968	0
		969	});
		970	}
		971
		972	=back
		973
		974	=head3 MESSAGE LOGGING
		975
		976	These methods allow you to log messages directly to a context, without
		977	going via your package context.
		978
		979	=over 4
		980
		981	=item $ctx->log ($level, $msg[, @params])
		982
		983	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
		984
		985	=item $logger = $ctx->logger ($level[, \$enabled])
		986
		987	Same as C<AnyEvent::Log::logger>, but uses the given context as log
		988	context.
		989
		990	=cut
		991
		992	*log = \&AnyEvent::Log::_log;
		993	*logger = \&AnyEvent::Log::_logger;
		994
		995	=back
		996
		997	=cut
		998
		999	package AnyEvent::Log;
		1000
		1001	=head1 CONFIGURATION VIA $ENV{PERL_ANYEVENT_LOG}
		1002
		1003	Logging can also be configured by setting the environment variable
		1004	C<PERL_ANYEVENT_LOG> (or C<AE_LOG>).
		1005
		1006	The value consists of one or more logging context specifications separated
		1007	by C<:> or whitespace. Each logging specification in turn starts with a
		1008	context name, followed by C<=>, followed by zero or more comma-separated
		1009	configuration directives, here are some examples:
		1010
		1011	# set default logging level
		1012	filter=warn
		1013
		1014	# log to file instead of to stderr
		1015	log=file=/tmp/mylog
		1016
		1017	# log to file in addition to stderr
		1018	log=+%file:%file=file=/tmp/mylog
		1019
		1020	# enable debug log messages, log warnings and above to syslog
		1021	filter=debug:log=+%warnings:%warnings=warn,syslog=LOG_LOCAL0
		1022
		1023	# log trace messages (only) from AnyEvent::Debug to file
		1024	AnyEvent::Debug=+%trace:%trace=only,trace,file=/tmp/tracelog
		1025
		1026	A context name in the log specification can be any of the following:
		1027
		1028	=over 4
		1029
		1030	=item C<collect>, C<filter>, C<log>
		1031
		1032	Correspond to the three predefined C<$AnyEvent::Log::COLLECT>,
		1033	C<AnyEvent::Log::FILTER> and C<$AnyEvent::Log::LOG> contexts.
		1034
		1035	=item C<%name>
		1036
		1037	Context names starting with a C<%> are anonymous contexts created when the
		1038	name is first mentioned. The difference to package contexts is that by
		1039	default they have no attached slaves.
		1040
		1041	=item a perl package name
		1042
		1043	Any other string references the logging context associated with the given
		1044	Perl C<package>. In the unlikely case where you want to specify a package
		1045	context that matches on of the other context name forms, you can add a
		1046	C<::> to the package name to force interpretation as a package.
		1047
		1048	=back
		1049
		1050	The configuration specifications can be any number of the following:
		1051
		1052	=over 4
		1053
		1054	=item C<stderr>
		1055
		1056	Configures the context to use Perl's C<warn> function (which typically
		1057	logs to C<STDERR>). Works like C<log_to_warn>.
		1058
		1059	=item C<file=>I<path>
		1060
		1061	Configures the context to log to a file with the given path. Works like
		1062	C<log_to_file>.
		1063
		1064	=item C<path=>I<path>
		1065
		1066	Configures the context to log to a file with the given path. Works like
		1067	C<log_to_path>.
		1068
		1069	=item C<syslog> or C<syslog=>I<expr>
		1070
		1071	Configures the context to log to syslog. If I<expr> is given, then it is
		1072	evaluated in the L<Sys::Syslog> package, so you could use:
		1073
		1074	log=syslog=LOG_LOCAL0
		1075
		1076	=item C<nolog>
		1077
		1078	Configures the context to not log anything by itself, which is the
		1079	default. Same as C<< $ctx->log_cb (undef) >>.
		1080
		1081	=item C<0> or C<off>
		1082
		1083	Sets the logging level of the context ot C<0>, i.e. all messages will be
		1084	filtered out.
		1085
		1086	=item C<all>
		1087
		1088	Enables all logging levels, i.e. filtering will effectively be switched
		1089	off (the default).
		1090
		1091	=item C<only>
		1092
		1093	Disables all logging levels, and changes the interpretation of following
		1094	level specifications to enable the specified level only.
		1095
		1096	Example: only enable debug messages for a context.
		1097
		1098	context=only,debug
		1099
		1100	=item C<except>
		1101
		1102	Enables all logging levels, and changes the interpretation of following
		1103	level specifications to disable that level. Rarely used.
		1104
		1105	Example: enable all logging levels except fatal and trace (this is rather
		1106	nonsensical).
		1107
		1108	filter=exept,fatal,trace
		1109
		1110	=item C<level>
		1111
		1112	Enables all logging levels, and changes the interpretation of following
		1113	level specifications to be "that level or any higher priority
		1114	message". This is the default.
		1115
		1116	Example: log anything at or above warn level.
		1117
		1118	filter=warn
		1119
		1120	# or, more verbose
		1121	filter=only,level,warn
		1122
		1123	=item C<1>..C<9> or a logging level name (C<error>, C<debug> etc.)
		1124
		1125	A numeric loglevel or the name of a loglevel will be interpreted according
		1126	to the most recent C<only>, C<except> or C<level> directive. By default,
		1127	specifying a logging level enables that and any higher priority messages.
		1128
		1129	=item C<+>I<context>
		1130
		1131	Attaches the named context as slave to the context.
		1132
		1133	=item C<+>
		1134
		1135	A line C<+> detaches all contexts, i.e. clears the slave list from the
		1136	context. Anonymous (C<%name>) contexts have no attached slaves by default,
		1137	but package contexts have the parent context as slave by default.
		1138
		1139	Example: log messages from My::Module to a file, do not send them to the
		1140	default log collector.
		1141
		1142	My::Module=+,file=/tmp/mymodulelog
		1143
		1144	=back
		1145
		1146	Any character can be escaped by prefixing it with a C<\> (backslash), as
		1147	usual, so to log to a file containing a comma, colon, backslash and some
		1148	spaces in the filename, you would do this:
		1149
		1150	PERL_ANYEVENT_LOG='log=file=/some\ \:file\ with\,\ \\-escapes'
		1151
		1152	Since whitespace (which includes newlines) is allowed, it is fine to
		1153	specify multiple lines in C<PERL_ANYEVENT_LOG>, e.g.:
		1154
		1155	PERL_ANYEVENT_LOG="
		1156	filter=warn
		1157	AnyEvent::Debug=+%trace
		1158	%trace=only,trace,+log
		1159	" myprog
		1160
		1161	Also, in the unlikely case when you want to concatenate specifications,
		1162	use whitespace as separator, as C<::> will be interpreted as part of a
		1163	module name, an empty spec with two separators:
		1164
		1165	PERL_ANYEVENT_LOG="$PERL_ANYEVENT_LOG MyMod=debug"
		1166
		1167	=cut
		1168
		1169	for (my $spec = $ENV{PERL_ANYEVENT_LOG}) {
		1170	my %anon;
		1171
		1172	my $pkg = sub {
		1173	$_[0] eq "log" ? $LOG
		1174	: $_[0] eq "filter" ? $FILTER
		1175	: $_[0] eq "collect" ? $COLLECT
		1176	: $_[0] =~ /^%(.+)$/ ? ($anon{$1} \|\|= ctx undef)
		1177	: $_[0] =~ /^(.*?)(?:::)?$/ ? ctx "$1" # egad :/
		1178	: die # never reached?
		1179	};
		1180
		1181	/\G[[:space:]]+/gc; # skip initial whitespace
		1182
		1183	while (/\G((?:[^:=[:space:]]+\|::\|\\.)+)=/gc) {
		1184	my $ctx = $pkg->($1);
		1185	my $level = "level";
		1186
		1187	while (/\G((?:[^,:[:space:]]+\|::\|\\.)+)/gc) {
		1188	for ("$1") {
		1189	if ($_ eq "stderr" ) { $ctx->log_to_warn;
		1190	} elsif (/^file=(.+)/ ) { $ctx->log_to_file ("$1");
		1191	} elsif (/^path=(.+)/ ) { $ctx->log_to_path ("$1");
		1192	} elsif (/syslog(?:=(.*))?/ ) { require Sys::Syslog; $ctx->log_to_syslog ($1);
		1193	} elsif ($_ eq "nolog" ) { $ctx->log_cb (undef);
		1194	} elsif (/^\+(.+)$/ ) { $ctx->attach ($pkg->("$1"));
		1195	} elsif ($_ eq "+" ) { $ctx->slaves;
		1196	} elsif ($_ eq "off" or $_ eq "0") { $ctx->level (0);
		1197	} elsif ($_ eq "all" ) { $ctx->level ("all");
		1198	} elsif ($_ eq "level" ) { $ctx->level ("all"); $level = "level";
		1199	} elsif ($_ eq "only" ) { $ctx->level ("off"); $level = "enable";
		1200	} elsif ($_ eq "except" ) { $ctx->level ("all"); $level = "disable";
		1201	} elsif (/^\d$/ ) { $ctx->$level ($_);
		1202	} elsif (exists $STR2LEVEL{$_} ) { $ctx->$level ($_);
		1203	} else { die "PERL_ANYEVENT_LOG ($spec): parse error at '$_'\n";
		1204	}
		1205	}
		1206
		1207	/\G,/gc or last;
		1208	}
		1209
		1210	/\G[:[:space:]]+/gc or last;
		1211	}
		1212
		1213	/\G[[:space:]]+/gc; # skip trailing whitespace
		1214
		1215	if (/\G(.+)/g) {
		1216	die "PERL_ANYEVENT_LOG ($spec): parse error at '$1'\n";
		1217	}
		1218	}
		1219
		1220	1;
		1221
		1222	=head1 EXAMPLES
		1223
		1224	This section shows some common configurations, both as code, and as
		1225	C<PERL_ANYEVENT_LOG> string.
		1226
		1227	=over 4
		1228
		1229	=item Setting the global logging level.
		1230
		1231	Either put C<PERL_ANYEVENT_VERBOSE=><number> into your environment before
		1232	running your program, use C<PERL_ANYEVENT_LOG> or modify the log level of
		1233	the root context at runtime:
		1234
		1235	PERL_ANYEVENT_VERBOSE=5 ./myprog
		1236
		1237	PERL_ANYEVENT_LOG=log=warn
		1238
		1239	$AnyEvent::Log::FILTER->level ("warn");
		1240
		1241	=item Append all messages to a file instead of sending them to STDERR.
		1242
		1243	This is affected by the global logging level.
		1244
		1245	$AnyEvent::Log::LOG->log_to_file ($path);
		1246
		1247	PERL_ANYEVENT_LOG=log=file=/some/path
844		1248
845	=item Write all messages with priority C<error> and higher to a file.	1249	=item Write all messages with priority C<error> and higher to a file.
846		1250
847	This writes them only when the global logging level allows it, because	1251	This writes them only when the global logging level allows it, because
848	it is attached to the default context which is invoked I<after> global	1252	it is attached to the default context which is invoked I<after> global
849	filtering.	1253	filtering.
850		1254
851	open my $fh, ">>", $path	1255	$AnyEvent::Log::FILTER->attach (
852	or die "$path: $!";	1256	new AnyEvent::Log::Ctx log_to_file => $path);
853		1257
854	$AnyEvent::Log::Default->attach (new AnyEvent::Log::Ctx	1258	PERL_ANYEVENT_LOG=filter=+%filelogger:%filelogger=file=/some/path
855	log_cb => sub { syswrite $fh, shift; 0 });
856		1259
857	This writes them regardless of the global logging level, because it is	1260	This writes them regardless of the global logging level, because it is
858	attached to the toplevel context, which receives all messages I<before>	1261	attached to the toplevel context, which receives all messages I<before>
859	the global filtering.	1262	the global filtering.
860		1263
861	$AnyEvent::Log::Top->attach (new AnyEvent::Log::Ctx	1264	$AnyEvent::Log::COLLECT->attach (
862	log_cb => sub { syswrite $fh, shift; 0 });	1265	new AnyEvent::Log::Ctx log_to_file => $path);
863		1266
		1267	PERL_ANYEVENT_LOG=%filelogger=file=/some/path:collect=+%filelogger
		1268
864	In both cases, messages are still written to STDOUT.	1269	In both cases, messages are still written to STDERR.
865		1270
866	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).	1271	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
867		1272
868	Attach the CyAnyEvent::Log::Default> context to the C<AnyEvent::Debug>	1273	Attach the C<$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.	1274	context - this simply circumvents the global filtering for trace messages.
871		1275
872	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;	1276	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
873	$debug->attach ($AnyEvent::Log::Default);	1277	$debug->attach ($AnyEvent::Log::LOG);
874	$debug->levels ("trace"); # not "level"!
875		1278
876	This of course works for any package.	1279	PERL_ANYEVENT_LOG=AnyEvent::Debug=+log
		1280
		1281	This of course works for any package, not just L<AnyEvent::Debug>, but
		1282	assumes the log level for AnyEvent::Debug hasn't been changed from the
		1283	default.
877		1284
878	=back	1285	=back
879		1286
880	=head1 AUTHOR	1287	=head1 AUTHOR
881		1288
882	Marc Lehmann <schmorp@schmorp.de>	1289	Marc Lehmann <schmorp@schmorp.de>
883	http://home.schmorp.de/	1290	http://home.schmorp.de/
884		1291
885	=cut	1292	=cut
		1293

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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 1.43 by root, Mon Sep 5 07:21:54 2011 UTC

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.15 by root, Sat Aug 20 02:16:59 2011 UTC vs.
Revision 1.43 by root, Mon Sep 5 07:21:54 2011 UTC