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

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.13 by root, Sat Aug 20 01:34:12 2011 UTC vs.
Revision 1.23 by root, Sun Aug 21 03:20:52 2011 UTC

…		…
8	use AnyEvent;	8	use AnyEvent;
9		9
10	AE::log debug => "hit my knee";	10	AE::log debug => "hit my knee";
11	AE::log warn => "it's a bit too hot";	11	AE::log warn => "it's a bit too hot";
12	AE::log error => "the flag was false!";	12	AE::log error => "the flag was false!";
13	AE::log fatal => "the bit toggled! run!";	13	AE::log fatal => "the bit toggled! run!"; # never returns
14		14
15	# "complex" use	15	# "complex" use (for speed sensitive code)
16	use AnyEvent::Log;	16	use AnyEvent::Log;
17		17
18	my $tracer = AnyEvent::Log::logger trace => \$my $trace;	18	my $tracer = AnyEvent::Log::logger trace => \$my $trace;
19		19
20	$tracer->("i am here") if $trace;	20	$tracer->("i am here") if $trace;
21	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;	21	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;
22		22
23	# configuration	23	# configuration
24		24
25	# set logging for this package to maximum	25	# set logging for the current package to errors and higher only
26	AnyEvent::Log::ctx->level ("all");	26	AnyEvent::Log::ctx->level ("error");
27		27
28	# set logging globally to anything below debug	28	# set logging level to suppress anything below "notice"
29	(AnyEvent::Log::ctx "")->level ("notice");	29	$AnyEvent::Log::FILTER->level ("notice");
		30
		31	# send all critical and higher priority messages to syslog,
		32	# regardless of (most) other settings
		33	$AnyEvent::Log::COLLECT->attach (new AnyEvent::Log::Ctx
		34	level => "critical",
		35	log_to_syslog => 0,
		36	);
30		37
31	# see also EXAMPLES, below	38	# see also EXAMPLES, below
32
33	# disable logging for package "AnyEvent" and all packages below it
34	AnyEvent->AnyEvent::Log::ctx->level (0);
35
36	# log everything below debug to a file, for the whole program
37	my $ctx = AnyEvent::Log::ctx;
38	$ctx->log_cb (sub { print FILE shift; 0 });
39	(AnyEvent::Log::ctx "")->add ($ctx);
40		39
41	=head1 DESCRIPTION	40	=head1 DESCRIPTION
42		41
43	This module implements a relatively simple "logging framework". It doesn't	42	This module implements a relatively simple "logging framework". It doesn't
44	attempt to be "the" logging solution or even "a" logging solution for	43	attempt to be "the" logging solution or even "a" logging solution for
45	AnyEvent - AnyEvent simply creates logging messages internally, and this	44	AnyEvent - AnyEvent simply creates logging messages internally, and this
46	module more or less exposes the mechanism, with some extra spiff to allow	45	module more or less exposes the mechanism, with some extra spiff to allow
47	using it from other modules as well.	46	using it from other modules as well.
48		47
49	Remember that the default verbosity level is C<0>, so nothing will be	48	Remember that the default verbosity level is C<0> (C<off>), so nothing
50	logged, unless you set C<PERL_ANYEVENT_VERBOSE> to a higher number before	49	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	50	before starting your program, or change the logging level at runtime with
52	something like:	51	something like:
53		52
54	use AnyEvent;	53	use AnyEvent::Log;
55	(AnyEvent::Log::ctx "")->level ("info");	54	AnyEvent::Log::FILTER->level ("info");
56		55
57	The design goal behind this module was to keep it simple (and small),	56	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	57	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	58	extensive enough for the most common tasks, such as logging to multiple
60	targets, or being able to log into a database.	59	targets, or being able to log into a database.
61		60
		61	The amount of documentation might indicate otherwise, but the module is
		62	still just below 300 lines of code.
		63
		64	=head1 LOGGING LEVELS
		65
		66	Logging levels in this module range from C<1> (highest priority) to C<9>
		67	(lowest priority). Note that the lowest numerical value is the highest
		68	priority, so when this document says "higher priority" it means "lower
		69	numerical value".
		70
		71	Instead of specifying levels by name you can also specify them by aliases:
		72
		73	LVL NAME SYSLOG PERL NOTE
		74	1 fatal emerg exit aborts program!
		75	2 alert
		76	3 critical crit
		77	4 error err die
		78	5 warn warning
		79	6 note notice
		80	7 info
		81	8 debug
		82	9 trace
		83
		84	As you can see, some logging levels have multiple aliases - the first one
		85	is the "official" name, the second one the "syslog" name (if it differs)
		86	and the third one the "perl" name, suggesting that you log C<die> messages
		87	at C<error> priority.
		88
		89	You can normally only log a single message at highest priority level
		90	(C<1>, C<fatal>), because logging a fatal message will also quit the
		91	program - so use it sparingly :)
		92
		93	Some methods also offer some extra levels, such as C<0>, C<off>, C<none>
		94	or C<all> - these are only valid in the methods they are documented for.
		95
62	=head1 LOGGING FUNCTIONS	96	=head1 LOGGING FUNCTIONS
63		97
64	These functions allow you to log messages. They always use the caller's	98	These functions allow you to log messages. They always use the caller's
65	package as a "logging module/source". Also, the main logging function is	99	package as a "logging context". Also, the main logging function C<log> is
66	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is	100	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is
67	loaded.	101	loaded.
68		102
69	=over 4	103	=over 4
70		104
…		…
75	use Carp ();	109	use Carp ();
76	use POSIX ();	110	use POSIX ();
77		111
78	use AnyEvent (); BEGIN { AnyEvent::common_sense }	112	use AnyEvent (); BEGIN { AnyEvent::common_sense }
79	use AnyEvent::Util ();	113	use AnyEvent::Util ();
		114
		115	our $VERSION = $AnyEvent::VERSION;
		116
		117	our ($COLLECT, $FILTER, $LOG);
80		118
81	our ($now_int, $now_str1, $now_str2);	119	our ($now_int, $now_str1, $now_str2);
82		120
83	# Format Time, not public - yet?	121	# Format Time, not public - yet?
84	sub ft($) {	122	sub ft($) {
…		…
89	if $now_int != $i;	127	if $now_int != $i;
90		128
91	"$now_str1$f$now_str2"	129	"$now_str1$f$now_str2"
92	}	130	}
93		131
94	our %CTX; # all logging contexts	132	our %CTX; # all package contexts
95		133
96	# creates a default package context object for the given package	134	# creates a default package context object for the given package
97	sub _pkg_ctx($) {	135	sub _pkg_ctx($) {
98	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";	136	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";
99		137
100	# link "parent" package	138	# link "parent" package
101	my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "AE::Log::Top";	139	my $parent = $_[0] =~ /^(.+)::/
		140	? $CTX{$1} \|\|= &_pkg_ctx ("$1")
		141	: $COLLECT;
102		142
103	$pkg = $CTX{$pkg} \|\|= &_pkg_ctx ($pkg);
104	$ctx->[2]{$pkg+0} = $pkg;	143	$ctx->[2]{$parent+0} = $parent;
105		144
106	$ctx	145	$ctx
107	}	146	}
108		147
109	=item AnyEvent::Log::log $level, $msg[, @args]	148	=item AnyEvent::Log::log $level, $msg[, @args]
110		149
111	Requests logging of the given C<$msg> with the given log level (1..9).	150	Requests logging of the given C<$msg> with the given log level, and
112	You can also use the following strings as log level: C<fatal> (1),	151	returns true if the message was logged I<somewhere>.
113	C<alert> (2), C<critical> (3), C<error> (4), C<warn> (5), C<note> (6),
114	C<info> (7), C<debug> (8), C<trace> (9).
115		152
116	For C<fatal> log levels, the program will abort.	153	For C<fatal> log levels, the program will abort.
117		154
118	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the	155	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the
119	C<$msg> is interpreted as an sprintf format string.	156	C<$msg> is interpreted as an sprintf format string.
…		…
125	supposed to return the message. It will be called only then the message	162	supposed to return the message. It will be called only then the message
126	actually gets logged, which is useful if it is costly to create the	163	actually gets logged, which is useful if it is costly to create the
127	message in the first place.	164	message in the first place.
128		165
129	Whether the given message will be logged depends on the maximum log level	166	Whether the given message will be logged depends on the maximum log level
130	and the caller's package.	167	and the caller's package. The return value can be used to ensure that
		168	messages or not "lost" - for example, when L<AnyEvent::Debug> detects a
		169	runtime error it tries to log it at C<die> level, but if that message is
		170	lost it simply uses warn.
131		171
132	Note that you can (and should) call this function as C<AnyEvent::log> or	172	Note that you can (and should) call this function as C<AnyEvent::log> or
133	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't	173	C<AE::log>, without C<use>-ing this module if possible (i.e. you don't
134	need any additional functionality), as those functions will load the	174	need any additional functionality), as those functions will load the
135	logging module on demand only. They are also much shorter to write.	175	logging module on demand only. They are also much shorter to write.
…		…
152		192
153	=cut	193	=cut
154		194
155	# also allow syslog equivalent names	195	# also allow syslog equivalent names
156	our %STR2LEVEL = (	196	our %STR2LEVEL = (
157	fatal => 1, emerg => 1,	197	fatal => 1, emerg => 1, exit => 1,
158	alert => 2,	198	alert => 2,
159	critical => 3, crit => 3,	199	critical => 3, crit => 3,
160	error => 4, err => 4,	200	error => 4, err => 4, die => 4,
161	warn => 5, warning => 5,	201	warn => 5, warning => 5,
162	note => 6, notice => 6,	202	note => 6, notice => 6,
163	info => 7,	203	info => 7,
164	debug => 8,	204	debug => 8,
165	trace => 9,	205	trace => 9,
…		…
195	? $level+0	235	? $level+0
196	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";	236	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";
197		237
198	my $mask = 1 << $level;	238	my $mask = 1 << $level;
199		239
200	my (%seen, @ctx, $now, $fmt);	240	my ($success, %seen, @ctx, $now, $fmt);
201		241
202	do	242	do
203	{	243	{
204	# skip if masked	244	# skip if masked
205	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {	245	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {
…		…
215	};	255	};
216		256
217	# format msg	257	# format msg
218	my $str = $ctx->[4]	258	my $str = $ctx->[4]
219	? $ctx->[4]($now, $_[0], $level, $format)	259	? $ctx->[4]($now, $_[0], $level, $format)
220	: $fmt \|\|= _format $now, $_[0], $level, $format;	260	: ($fmt \|\|= _format $now, $_[0], $level, $format);
221		261
		262	$success = 1;
		263
222	$ctx->[3]($str);	264	$ctx->[3]($str)
		265	or push @ctx, values %{ $ctx->[2] }; # not consumed - propagate
		266	} else {
		267	push @ctx, values %{ $ctx->[2] }; # not masked - propagate
223	}	268	}
224
225	# not masked, not consumed - propagate to parent contexts
226	push @ctx, values %{ $ctx->[2] };
227	}	269	}
228	}	270	}
229	while $ctx = pop @ctx;	271	while $ctx = pop @ctx;
230		272
231	exit 1 if $level <= 1;	273	exit 1 if $level <= 1;
		274
		275	$success
232	}	276	}
233		277
234	sub log($$;@) {	278	sub log($$;@) {
235	_log	279	_log
236	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	280	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
…		…
240	AnyEvent::log = AE::log = \&log;	284	AnyEvent::log = AE::log = \&log;
241		285
242	=item $logger = AnyEvent::Log::logger $level[, \$enabled]	286	=item $logger = AnyEvent::Log::logger $level[, \$enabled]
243		287
244	Creates a code reference that, when called, acts as if the	288	Creates a code reference that, when called, acts as if the
245	C<AnyEvent::Log::log> function was called at this point with the givne	289	C<AnyEvent::Log::log> function was called at this point with the given
246	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with	290	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with
247	the C<AnyEvent::Log::log> function:	291	the C<AnyEvent::Log::log> function:
248		292
249	my $debug_log = AnyEvent::Log::logger "debug";	293	my $debug_log = AnyEvent::Log::logger "debug";
250		294
…		…
275	# and later in your program	319	# and later in your program
276	$debug_log->("yo, stuff here") if $debug;	320	$debug_log->("yo, stuff here") if $debug;
277		321
278	$debug and $debug_log->("123");	322	$debug and $debug_log->("123");
279		323
280	Note: currently the enabled var is always true - that will be fixed in a
281	future version :)
282
283	=cut	324	=cut
284		325
285	our %LOGGER;	326	our %LOGGER;
286		327
287	# re-assess logging status for all loggers	328	# re-assess logging status for all loggers
288	sub _reassess {	329	sub _reassess {
		330	local $SIG{__DIE__};
		331	my $die = sub { die };
		332
289	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {	333	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {
290	my ($ctx, $level, $renabled) = @$_;	334	my ($ctx, $level, $renabled) = @$_;
291		335
292	# to detect whether a message would be logged, we # actually	336	# to detect whether a message would be logged, we actually
293	# try to log one and die. this isn't fast, but we can be	337	# try to log one and die. this isn't fast, but we can be
294	# sure that the logging decision is correct :)	338	# sure that the logging decision is correct :)
295		339
296	$$renabled = !eval {	340	$$renabled = !eval {
297	local $SIG{__DIE__};
298
299	_log $ctx, $level, sub { die };	341	_log $ctx, $level, $die;
300		342
301	1	343	1
302	};	344	};
303
304	$$renabled = 1; # TODO
305	}	345	}
306	}	346	}
307		347
308	sub _logger($;$) {	348	sub _logger {
309	my ($ctx, $level, $renabled) = @_;	349	my ($ctx, $level, $renabled) = @_;
310
311	$renabled \|\|= \my $enabled;
312		350
313	$$renabled = 1;	351	$$renabled = 1;
314		352
315	my $logger = [$ctx, $level, $renabled];	353	my $logger = [$ctx, $level, $renabled];
316		354
…		…
356	timestamp, context, level and string message and formats it in the way	394	timestamp, context, level and string message and formats it in the way
357	it should be logged) and a logging callback (which is responsible for	395	it should be logged) and a logging callback (which is responsible for
358	actually logging the formatted message and telling C<AnyEvent::Log>	396	actually logging the formatted message and telling C<AnyEvent::Log>
359	whether it has consumed the message, or whether it should be propagated).	397	whether it has consumed the message, or whether it should be propagated).
360		398
361	For propagation, a context can have any number of attached I<parent	399	For propagation, a context can have any number of attached I<slave
362	contexts>. Any message that is neither masked by the logging mask nor	400	contexts>. Any message that is neither masked by the logging mask nor
363	masked by the logging callback returning true will be passed to all parent	401	masked by the logging callback returning true will be passed to all slave
364	contexts.	402	contexts.
365		403
366	Each call to a logging function will log the message at most once per	404	Each call to a logging function will log the message at most once per
367	context, so it does not matter (much) if there are cycles or if the	405	context, so it does not matter (much) if there are cycles or if the
368	message can arrive at the same context via multiple paths.	406	message can arrive at the same context via multiple paths.
…		…
372	By default, all logging contexts have an full set of log levels ("all"), a	410	By default, all logging contexts have an full set of log levels ("all"), a
373	disabled logging callback and the default formatting callback.	411	disabled logging callback and the default formatting callback.
374		412
375	Package contexts have the package name as logging title by default.	413	Package contexts have the package name as logging title by default.
376		414
377	They have exactly one parent - the context of the "parent" package. The	415	They have exactly one slave - the context of the "parent" package. The
378	parent package is simply defined to be the package name without the last	416	parent package is simply defined to be the package name without the last
379	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,	417	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
380	and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the	418	and C<AnyEvent> becomes ... C<$AnyEvent::Log::COLLECT> which is the
381	exception of the rule - just like the parent of any package name in	419	exception of the rule - just like the "parent" of any single-component
382	Perl is C<main>, the default parent of any top-level package context is	420	package name in Perl is C<main>, the default slave of any top-level
383	C<AnyEvent::Log::Top>.	421	package context is C<$AnyEvent::Log::COLLECT>.
384		422
385	Since perl packages form only an approximate hierarchy, this parent	423	Since perl packages form only an approximate hierarchy, this slave
386	context can of course be removed.	424	context can of course be removed.
387		425
388	All other (anonymous) contexts have no parents and an empty title by	426	All other (anonymous) contexts have no slaves and an empty title by
389	default.	427	default.
390		428
391	When the module is loaded it creates the default context called	429	When the module is loaded it creates the C<$AnyEvent::Log::LOG> logging
392	C<AnyEvent::Log::Default> (also stored in C<$AnyEvent::Log::Default>),	430	context that simply logs everything via C<warn>, without propagating
393	which simply logs everything to STDERR and doesn't propagate anything
394	anywhere by default. The purpose of the default context is to provide	431	anything anywhere by default. The purpose of this context is to provide
395	a convenient place to override the global logging target or to attach	432	a convenient place to override the global logging target or to attach
396	additional log targets. It's not meant for filtering.	433	additional log targets. It's not meant for filtering.
397		434
398	It then creates the root context called C<AnyEvent::Log::Root> (also	435	It then creates the C<$AnyEvent::Log::FILTER> context whose
399	stored in C<$AnyEvent::Log::Root>) and sets its log level set to all	436	purpose is to suppress all messages with priority higher
400	levels up to the one specified by C<$ENV{PERL_ANYEVENT_VERBOSE}>. It	437	than C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the
401	then attached the default logging context to it. The purpose of the root	438	C<$AnyEvent::Log::LOG> context to it. The purpose of the filter context
402	context is to simply provide filtering according to some global log level.	439	is to simply provide filtering according to some global log level.
403		440
404	Finally it creates the top-level package context called	441	Finally it creates the top-level package context C<$AnyEvent::Log::COLLECT>
405	C<AnyEvent::Log::Top> (also stored in, you might have guessed,	442	and attaches the C<$AnyEvent::Log::FILTER> context to it, but otherwise
406	C<$AnyEvent::Log::Top>) and attached the root context but otherwise leaves
407	it at default config. It's purpose is simply to collect all log messages	443	leaves it at default config. Its purpose is simply to collect all log
408	system-wide.	444	messages system-wide.
409		445
410	These three special contexts can also be referred to by the	446	The hierarchy is then:
411	package/context names C<AE::Log::Default>, C<AE::Log::Root> and
412	C<AE::Log::Top>.
413		447
		448	any package, eventually -> $COLLECT -> $FILTER -> $LOG
		449
414	The effect of all this is that log messages, by default, wander up	450	The effect of all this is that log messages, by default, wander up to the
415	to the root context where log messages with lower priority then	451	C<$AnyEvent::Log::COLLECT> context where all messages normally end up,
		452	from there to C<$AnyEvent::Log::FILTER> where log messages with lower
416	C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered away and then to the	453	priority then C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered out and then
417	AnyEvent::Log::Default context to be logged to STDERR.	454	to the C<$AnyEvent::Log::LOG> context to be passed to C<warn>.
418		455
419	Splitting the top level context into three contexts makes it easy to set	456	This makes it easy to set a global logging level (by modifying $FILTER),
420	a global logging level (by modifying the root context), but still allow	457	but still allow other contexts to send, for example, their debug and trace
421	other contexts to log, for example, their debug and trace messages to the
422	default target despite the global logging level, or to attach additional	458	messages to the $LOG target despite the global logging level, or to attach
423	log targets that log messages, regardless of the global logging level.	459	additional log targets that log messages, regardless of the global logging
		460	level.
424		461
425	It also makes it easy to replace the default STDERR-logger by something	462	It also makes it easy to modify the default warn-logger ($LOG) to
426	that logs to a file, or to attach additional logging targets.	463	something that logs to a file, or to attach additional logging targets
		464	(such as loggign to a file) by attaching it to $FILTER.
427		465
428	=head2 CREATING/FINDING/DESTROYING CONTEXTS	466	=head2 CREATING/FINDING/DESTROYING CONTEXTS
429		467
430	=over 4	468	=over 4
431		469
…		…
453	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"	491	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"
454	}	492	}
455		493
456	=item AnyEvent::Log::reset	494	=item AnyEvent::Log::reset
457		495
458	Deletes all contexts and recreates the default hierarchy, i.e. resets the	496	Resets all package contexts and recreates the default hierarchy if
459	logging subsystem to defaults.	497	necessary, i.e. resets the logging subsystem to defaults, as much as
		498	possible. This process keeps references to contexts held by other parts of
		499	the program intact.
460		500
461	This can be used to implement config-file (re-)loading: before loading a	501	This can be used to implement config-file (re-)loading: before loading a
462	configuration, reset all contexts.	502	configuration, reset all contexts.
463		503
464	=cut	504	=cut
465		505
466	sub reset {	506	sub reset {
467	@$_ = () for values %CTX; # just to be sure - to kill circular logging dependencies	507	# hard to kill complex data structures
468	%CTX = ();	508	# we "recreate" all package loggers and reset the hierarchy
		509	while (my ($k, $v) = each %CTX) {
		510	@$v = ($k, (1 << 10) - 1 - 1, { });
469		511
470	my $default = ctx undef;	512	$v->attach ($k =~ /^(.+)::/ ? $CTX{$1} : $AnyEvent::Log::COLLECT);
471	$default->title ("AnyEvent::Log::Default");	513	}
		514
		515	@$_ = ($_->[0], (1 << 10) - 1 - 1)
		516	for $LOG, $FILTER, $COLLECT;
		517
		518	$LOG->slaves;
		519	$LOG->title ('$AnyEvent::Log::LOG');
472	$default->log_cb (sub {	520	$LOG->log_cb (sub {
473	print STDERR shift;	521	warn shift;
474	0	522	0
475	});	523	});
476	$AnyEvent::Log::Default = $CTX{"AnyEvent::Log::Default"} = $CTX{"AE::Log::Default"} = $default;
477		524
478	my $root = ctx undef;	525	$FILTER->slaves ($LOG);
479	$root->title ("AnyEvent::Log::Root");	526	$FILTER->title ('$AnyEvent::Log::FILTER');
480	$root->level ($AnyEvent::VERBOSE);	527	$FILTER->level ($AnyEvent::VERBOSE);
481	$root->attach ($default);
482	$AnyEvent::Log::Root = $CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $root;
483		528
484	my $top = ctx undef;	529	$COLLECT->slaves ($FILTER);
485	$top->title ("AnyEvent::Log::Top");	530	$COLLECT->title ('$AnyEvent::Log::COLLECT');
486	$top->attach ($root);	531
487	$AnyEvent::Log::Top = $CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $top;	532	_reassess;
488	}	533	}
		534
		535	# create the default logger contexts
		536	$LOG = ctx undef;
		537	$FILTER = ctx undef;
		538	$COLLECT = ctx undef;
489		539
490	AnyEvent::Log::reset;	540	AnyEvent::Log::reset;
491		541
492	# hello, CPAN, please catch me	542	# hello, CPAN, please catch me
493	package AnyEvent::Log::Default;
494	package AE::Log::Default;
495	package AnyEvent::Log::Root;
496	package AE::Log::Root;
497	package AnyEvent::Log::Top;	543	package AnyEvent::Log::LOG;
498	package AE::Log::Top;	544	package AE::Log::LOG;
		545	package AnyEvent::Log::FILTER;
		546	package AE::Log::FILTER;
		547	package AnyEvent::Log::COLLECT;
		548	package AE::Log::COLLECT;
499		549
500	package AnyEvent::Log::Ctx;	550	package AnyEvent::Log::Ctx;
501		551
502	# 0 1 2 3 4	552	# 0 1 2 3 4
503	# [$title, $level, %$parents, &$logcb, &$fmtcb]	553	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
504		554
505	=item $ctx = new AnyEvent::Log::Ctx methodname => param...	555	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
506		556
507	This is a convenience constructor that makes it simpler to construct	557	This is a convenience constructor that makes it simpler to construct
508	anonymous logging contexts.	558	anonymous logging contexts.
…		…
511	name as the key with the value as parameter, unless the value is an	561	name as the key with the value as parameter, unless the value is an
512	arrayref, in which case it calls the method with the contents of the	562	arrayref, in which case it calls the method with the contents of the
513	array. The methods are called in the same order as specified.	563	array. The methods are called in the same order as specified.
514		564
515	Example: create a new logging context and set both the default logging	565	Example: create a new logging context and set both the default logging
516	level, some parent contexts and a logging callback.	566	level, some slave contexts and a logging callback.
517		567
518	$ctx = new AnyEvent::Log::Ctx	568	$ctx = new AnyEvent::Log::Ctx
519	title => "dubious messages",	569	title => "dubious messages",
520	level => "error",	570	level => "error",
521	log_cb => sub { print STDOUT shift; 0 },	571	log_cb => sub { print STDOUT shift; 0 },
522	parents => [$ctx1, $ctx, $ctx2],	572	slaves => [$ctx1, $ctx, $ctx2],
523	;	573	;
524		574
525	=back	575	=back
526		576
527	=cut	577	=cut
…		…
640	AnyEvent::Log::_reassess;	690	AnyEvent::Log::_reassess;
641	}	691	}
642		692
643	=back	693	=back
644		694
645	=head3 PARENT CONTEXTS	695	=head3 SLAVE CONTEXTS
646		696
647	The following methods attach and detach another logging context to a	697	The following methods attach and detach another logging context to a
648	logging context.	698	logging context.
649		699
650	Log messages are propagated to all parent contexts, unless the logging	700	Log messages are propagated to all slave contexts, unless the logging
651	callback consumes the message.	701	callback consumes the message.
652		702
653	=over 4	703	=over 4
654		704
655	=item $ctx->attach ($ctx2[, $ctx3...])	705	=item $ctx->attach ($ctx2[, $ctx3...])
656		706
657	Attaches the given contexts as parents to this context. It is not an error	707	Attaches the given contexts as slaves to this context. It is not an error
658	to add a context twice (the second add will be ignored).	708	to add a context twice (the second add will be ignored).
659		709
660	A context can be specified either as package name or as a context object.	710	A context can be specified either as package name or as a context object.
661		711
662	=item $ctx->detach ($ctx2[, $ctx3...])	712	=item $ctx->detach ($ctx2[, $ctx3...])
663		713
664	Removes the given parents from this context - it's not an error to attempt	714	Removes the given slaves from this context - it's not an error to attempt
665	to remove a context that hasn't been added.	715	to remove a context that hasn't been added.
666		716
667	A context can be specified either as package name or as a context object.	717	A context can be specified either as package name or as a context object.
668		718
669	=item $ctx->parents ($ctx2[, $ctx3...])	719	=item $ctx->slaves ($ctx2[, $ctx3...])
670		720
671	Replaces all parents attached to this context by the ones given.	721	Replaces all slaves attached to this context by the ones given.
672		722
673	=cut	723	=cut
674		724
675	sub attach {	725	sub attach {
676	my $ctx = shift;	726	my $ctx = shift;
…		…
684		734
685	delete $ctx->[2]{$_+0}	735	delete $ctx->[2]{$_+0}
686	for map { AnyEvent::Log::ctx $_ } @_;	736	for map { AnyEvent::Log::ctx $_ } @_;
687	}	737	}
688		738
689	sub parents {	739	sub slaves {
690	undef $_[0][2];	740	undef $_[0][2];
691	&attach;	741	&attach;
692	}	742	}
693		743
694	=back	744	=back
695		745
696	=head3 MESSAGE LOGGING	746	=head3 LOG TARGETS
697		747
698	The following methods configure how the logging context actually does	748	The following methods configure how the logging context actually does
699	the logging (which consists of formatting the message and printing it or	749	the logging (which consists of formatting the message and printing it or
700	whatever it wants to do with it) and also allows you to log messages	750	whatever it wants to do with it).
701	directly to a context, without going via your package context.
702		751
703	=over 4	752	=over 4
704		753
705	=item $ctx->log_cb ($cb->($str))	754	=item $ctx->log_cb ($cb->($str)
706		755
707	Replaces the logging callback on the context (C<undef> disables the	756	Replaces the logging callback on the context (C<undef> disables the
708	logging callback).	757	logging callback).
709		758
710	The logging callback is responsible for handling formatted log messages	759	The logging callback is responsible for handling formatted log messages
711	(see C<fmt_cb> below) - normally simple text strings that end with a	760	(see C<fmt_cb> below) - normally simple text strings that end with a
712	newline (and are possibly multiline themselves).	761	newline (and are possibly multiline themselves).
713		762
714	It also has to return true iff it has consumed the log message, and false	763	It also has to return true iff it has consumed the log message, and false
715	if it hasn't. Consuming a message means that it will not be sent to any	764	if it hasn't. Consuming a message means that it will not be sent to any
716	parent context. When in doubt, return C<0> from your logging callback.	765	slave context. When in doubt, return C<0> from your logging callback.
717		766
718	Example: a very simple logging callback, simply dump the message to STDOUT	767	Example: a very simple logging callback, simply dump the message to STDOUT
719	and do not consume it.	768	and do not consume it.
720		769
721	$ctx->log_cb (sub { print STDERR shift; 0 });	770	$ctx->log_cb (sub { print STDERR shift; 0 });
…		…
729	your program.	778	your program.
730		779
731	$ctx->levels ("debug", "trace");	780	$ctx->levels ("debug", "trace");
732	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages	781	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages
733		782
734	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	783	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $orig_ctx, $level, $message))
735		784
736	Replaces the formatting callback on the context (C<undef> restores the	785	Replaces the formatting callback on the context (C<undef> restores the
737	default formatter).	786	default formatter).
738		787
739	The callback is passed the (possibly fractional) timestamp, the original	788	The callback is passed the (possibly fractional) timestamp, the original
740	logging context, the (numeric) logging level and the raw message string and needs to	789	logging context, the (numeric) logging level and the raw message string
741	return a formatted log message. In most cases this will be a string, but	790	and needs to return a formatted log message. In most cases this will be a
742	it could just as well be an array reference that just stores the values.	791	string, but it could just as well be an array reference that just stores
		792	the values.
		793
		794	If, for some reaosn, you want to use C<caller> to find out more baout the
		795	logger then you should walk up the call stack until you are no longer
		796	inside the C<AnyEvent::Log> package.
743		797
744	Example: format just the raw message, with numeric log level in angle	798	Example: format just the raw message, with numeric log level in angle
745	brackets.	799	brackets.
746		800
747	$ctx->fmt_cb (sub {	801	$ctx->fmt_cb (sub {
…		…
764	"$msg->[3]";	818	"$msg->[3]";
765		819
766	0	820	0
767	});	821	});
768		822
		823	=item $ctx->log_to_file ($path)
		824
		825	Sets the C<log_cb> to log to a file (by appending), unbuffered.
		826
		827	=item $ctx->log_to_path ($path)
		828
		829	Same as C<< ->log_to_file >>, but opens the file for each message. This
		830	is much slower, but allows you to change/move/rename/delete the file at
		831	basically any time.
		832
		833	=item $ctx->log_to_syslog ([$log_flags])
		834
		835	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and all
		836	the others in the obvious way. If specified, then the C<$log_flags> are
		837	simply or'ed onto the priority argument and can contain any C<LOG_xxx>
		838	flags valid for Sys::Syslog::syslog, except for the priority levels.
		839
		840	Note that this function also sets a C<fmt_cb> - the logging part requires
		841	an array reference with [$level, $str] as input.
		842
769	=cut	843	=cut
770		844
771	sub log_cb {	845	sub log_cb {
772	my ($ctx, $cb) = @_;	846	my ($ctx, $cb) = @_;
773		847
…		…
778	my ($ctx, $cb) = @_;	852	my ($ctx, $cb) = @_;
779		853
780	$ctx->[4] = $cb;	854	$ctx->[4] = $cb;
781	}	855	}
782		856
783	=item $ctx->log ($level, $msg[, @params])	857	sub log_to_file {
784		858	my ($ctx, $path) = @_;
785	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
786
787	=item $logger = $ctx->logger ($level[, \$enabled])
788
789	Same as C<AnyEvent::Log::logger>, but uses the given context as log
790	context.
791
792	=cut
793
794	*log = \&AnyEvent::Log::_log;
795	*logger = \&AnyEvent::Log::_logger;
796
797	1;
798
799	=back
800
801	=head1 EXAMPLES
802
803	This section shows some common configurations.
804
805	=over 4
806
807	=item Setting the global logging level.
808
809	Either put PERL_ANYEVENT_VERBOSE=<number> into your environment before
810	running your program, or modify the log level of the root context:
811
812	PERL_ANYEVENT_VERBOSE=5 ./myprog
813
814	$AnyEvent::Log::Root->level ("warn");
815
816	=item Append all messages to a file instead of sending them to STDERR.
817
818	This is affected by the global logging level.
819		859
820	open my $fh, ">>", $path	860	open my $fh, ">>", $path
821	or die "$path: $!";	861	or die "$path: $!";
822		862
823	$AnyEvent::Log::Default->log_cb (sub {	863	$ctx->log_cb (sub {
824	syswrite $fh, shift;	864	syswrite $fh, shift;
825	0	865	0
826	});	866	});
		867	}
		868
		869	sub log_to_file {
		870	my ($ctx, $path) = @_;
		871
		872	$ctx->log_cb (sub {
		873	open my $fh, ">>", $path
		874	or die "$path: $!";
		875
		876	syswrite $fh, shift;
		877	0
		878	});
		879	}
		880
		881	sub log_to_syslog {
		882	my ($ctx, $flags) = @_;
		883
		884	require Sys::Syslog;
		885
		886	$ctx->fmt_cb (sub {
		887	my $str = $_[3];
		888	$str =~ s/\n(?=.)/\n+ /g;
		889
		890	[$_[2], "($_[1][0]) $str"]
		891	});
		892
		893	$ctx->log_cb (sub {
		894	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;
		895
		896	Sys::Syslog::syslog ($flags \| ($lvl - 1), $_)
		897	for split /\n/, $_[0][1];
		898
		899	0
		900	});
		901	}
		902
		903	=back
		904
		905	=head3 MESSAGE LOGGING
		906
		907	These methods allow you to log messages directly to a context, without
		908	going via your package context.
		909
		910	=over 4
		911
		912	=item $ctx->log ($level, $msg[, @params])
		913
		914	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
		915
		916	=item $logger = $ctx->logger ($level[, \$enabled])
		917
		918	Same as C<AnyEvent::Log::logger>, but uses the given context as log
		919	context.
		920
		921	=cut
		922
		923	*log = \&AnyEvent::Log::_log;
		924	*logger = \&AnyEvent::Log::_logger;
		925
		926	1;
		927
		928	=back
		929
		930	=head1 EXAMPLES
		931
		932	This section shows some common configurations.
		933
		934	=over 4
		935
		936	=item Setting the global logging level.
		937
		938	Either put PERL_ANYEVENT_VERBOSE=<number> into your environment before
		939	running your program, or modify the log level of the root context:
		940
		941	PERL_ANYEVENT_VERBOSE=5 ./myprog
		942
		943	$AnyEvent::Log::FILTER->level ("warn");
		944
		945	=item Append all messages to a file instead of sending them to STDERR.
		946
		947	This is affected by the global logging level.
		948
		949	$AnyEvent::Log::LOG->log_to_file ($path); (sub {
827		950
828	=item Write all messages with priority C<error> and higher to a file.	951	=item Write all messages with priority C<error> and higher to a file.
829		952
830	This writes them only when the global logging level allows it, because	953	This writes them only when the global logging level allows it, because
831	it is attached to the default context which is invoked I<after> global	954	it is attached to the default context which is invoked I<after> global
832	filtering.	955	filtering.
833		956
834	open my $fh, ">>", $path	957	$AnyEvent::Log::FILTER->attach
835	or die "$path: $!";	958	new AnyEvent::Log::Ctx log_to_file => $path);
836
837	$AnyEvent::Log::Default->attach (new AnyEvent::Log::Ctx
838	log_cb => sub { syswrite $fh, shift; 0 });
839		959
840	This writes them regardless of the global logging level, because it is	960	This writes them regardless of the global logging level, because it is
841	attached to the toplevel context, which receives all messages I<before>	961	attached to the toplevel context, which receives all messages I<before>
842	the global filtering.	962	the global filtering.
843		963
844	$AnyEvent::Log::Top->attach (new AnyEvent::Log::Ctx	964	$AnyEvent::Log::COLLECT->attach (
845	log_cb => sub { syswrite $fh, shift; 0 });	965	new AnyEvent::Log::Ctx log_to_file => $path);
846		966
847	In both cases, messages are still written to STDOUT.	967	In both cases, messages are still written to STDERR.
848		968
849	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).	969	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
850		970
851	Attach the CyAnyEvent::Log::Default> context to the C<AnyEvent::Debug>	971	Attach the C<$AnyEvent::Log::LOG> context to the C<AnyEvent::Debug>
852	context and increase the C<AnyEvent::Debug> logging level - this simply
853	circumvents the global filtering for trace messages.	972	context - this simply circumvents the global filtering for trace messages.
854		973
855	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;	974	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
856	$debug->attach ($AnyEvent::Log::Default);	975	$debug->attach ($AnyEvent::Log::LOG);
857	$debug->levels ("trace"); # not "level"!
858		976
859	This of course works for any package.	977	This of course works for any package, not just L<AnyEvent::Debug>, but
		978	assumes the log level for AnyEvent::Debug hasn't been changed from the
		979	default.
860		980
861	=back	981	=back
862		982
863	=head1 AUTHOR	983	=head1 AUTHOR
864		984

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents): Revision 1.13 by root, Sat Aug 20 01:34:12 2011 UTC vs. Revision 1.23 by root, Sun Aug 21 03:20:52 2011 UTC

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Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.13 by root, Sat Aug 20 01:34:12 2011 UTC vs.
Revision 1.23 by root, Sun Aug 21 03:20:52 2011 UTC