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

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.14 by root, Sat Aug 20 01:49:27 2011 UTC vs.
Revision 1.21 by root, Sat Aug 20 22:33:08 2011 UTC

…		…
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 globally to anything below debug
29	(AnyEvent::Log::ctx "")->level ("notice");	29	$AnyEvent::Log::FILTER->level ("notice");
30		30
31	# see also EXAMPLES, below	31	# 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		32
41	=head1 DESCRIPTION	33	=head1 DESCRIPTION
42		34
43	This module implements a relatively simple "logging framework". It doesn't	35	This module implements a relatively simple "logging framework". It doesn't
44	attempt to be "the" logging solution or even "a" logging solution for	36	attempt to be "the" logging solution or even "a" logging solution for
45	AnyEvent - AnyEvent simply creates logging messages internally, and this	37	AnyEvent - AnyEvent simply creates logging messages internally, and this
46	module more or less exposes the mechanism, with some extra spiff to allow	38	module more or less exposes the mechanism, with some extra spiff to allow
47	using it from other modules as well.	39	using it from other modules as well.
48		40
49	Remember that the default verbosity level is C<0>, so nothing will be	41	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	42	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	43	before starting your program, or change the logging level at runtime with
52	something like:	44	something like:
53		45
54	use AnyEvent;	46	use AnyEvent::Log;
55	(AnyEvent::Log::ctx "")->level ("info");	47	AnyEvent::Log::FILTER->level ("info");
56		48
57	The design goal behind this module was to keep it simple (and small),	49	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	50	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	51	extensive enough for the most common tasks, such as logging to multiple
60	targets, or being able to log into a database.	52	targets, or being able to log into a database.
61		53
62	The amount of documentation might indicate otherwise, but the module is	54	The amount of documentation might indicate otherwise, but the module is
63	still just 240 lines or so.	55	still just below 300 lines of code.
		56
		57	=head1 LOGGING LEVELS
		58
		59	Logging levels in this module range from C<1> (highest priority) to C<9>
		60	(lowest priority). Note that the lowest numerical value is the highest
		61	priority, so when this document says "higher priority" it means "lower
		62	numerical value".
		63
		64	Instead of specifying levels by name you can also specify them by aliases:
		65
		66	LVL NAME SYSLOG PERL NOTE
		67	1 fatal emerg exit aborts program!
		68	2 alert
		69	3 critical crit
		70	4 error err die
		71	5 warn warning
		72	6 note notice
		73	7 info
		74	8 debug
		75	9 trace
		76
		77	As you can see, some logging levels have multiple aliases - the first one
		78	is the "official" name, the second one the "syslog" name (if it differs)
		79	and the third one the "perl" name, suggesting that you log C<die> messages
		80	at C<error> priority.
		81
		82	You can normally only log a single message at highest priority level
		83	(C<1>, C<fatal>), because logging a fatal message will also quit the
		84	program - so use it sparingly :)
		85
		86	Some methods also offer some extra levels, such as C<0>, C<off>, C<none>
		87	or C<all> - these are only valid in the methods they are documented for.
64		88
65	=head1 LOGGING FUNCTIONS	89	=head1 LOGGING FUNCTIONS
66		90
67	These functions allow you to log messages. They always use the caller's	91	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	92	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	93	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is
70	loaded.	94	loaded.
71		95
72	=over 4	96	=over 4
73		97
…		…
80		104
81	use AnyEvent (); BEGIN { AnyEvent::common_sense }	105	use AnyEvent (); BEGIN { AnyEvent::common_sense }
82	use AnyEvent::Util ();	106	use AnyEvent::Util ();
83		107
84	our $VERSION = $AnyEvent::VERSION;	108	our $VERSION = $AnyEvent::VERSION;
		109
		110	our ($COLLECT, $FILTER, $LOG);
85		111
86	our ($now_int, $now_str1, $now_str2);	112	our ($now_int, $now_str1, $now_str2);
87		113
88	# Format Time, not public - yet?	114	# Format Time, not public - yet?
89	sub ft($) {	115	sub ft($) {
…		…
94	if $now_int != $i;	120	if $now_int != $i;
95		121
96	"$now_str1$f$now_str2"	122	"$now_str1$f$now_str2"
97	}	123	}
98		124
99	our %CTX; # all logging contexts	125	our %CTX; # all package contexts
100		126
101	# creates a default package context object for the given package	127	# creates a default package context object for the given package
102	sub _pkg_ctx($) {	128	sub _pkg_ctx($) {
103	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";	129	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";
104		130
105	# link "parent" package	131	# link "parent" package
106	my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "AE::Log::Top";	132	my $parent = $_[0] =~ /^(.+)::/
		133	? $CTX{$1} \|\|= &_pkg_ctx ("$1")
		134	: $COLLECT;
107		135
108	$pkg = $CTX{$pkg} \|\|= &_pkg_ctx ($pkg);
109	$ctx->[2]{$pkg+0} = $pkg;	136	$ctx->[2]{$parent+0} = $parent;
110		137
111	$ctx	138	$ctx
112	}	139	}
113		140
114	=item AnyEvent::Log::log $level, $msg[, @args]	141	=item AnyEvent::Log::log $level, $msg[, @args]
115		142
116	Requests logging of the given C<$msg> with the given log level (1..9).	143	Requests logging of the given C<$msg> with the given log level.
117	You can also use the following strings as log level: C<fatal> (1),
118	C<alert> (2), C<critical> (3), C<error> (4), C<warn> (5), C<note> (6),
119	C<info> (7), C<debug> (8), C<trace> (9).
120		144
121	For C<fatal> log levels, the program will abort.	145	For C<fatal> log levels, the program will abort.
122		146
123	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the	147	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.	148	C<$msg> is interpreted as an sprintf format string.
…		…
157		181
158	=cut	182	=cut
159		183
160	# also allow syslog equivalent names	184	# also allow syslog equivalent names
161	our %STR2LEVEL = (	185	our %STR2LEVEL = (
162	fatal => 1, emerg => 1,	186	fatal => 1, emerg => 1, exit => 1,
163	alert => 2,	187	alert => 2,
164	critical => 3, crit => 3,	188	critical => 3, crit => 3,
165	error => 4, err => 4,	189	error => 4, err => 4, die => 4,
166	warn => 5, warning => 5,	190	warn => 5, warning => 5,
167	note => 6, notice => 6,	191	note => 6, notice => 6,
168	info => 7,	192	info => 7,
169	debug => 8,	193	debug => 8,
170	trace => 9,	194	trace => 9,
…		…
220	};	244	};
221		245
222	# format msg	246	# format msg
223	my $str = $ctx->[4]	247	my $str = $ctx->[4]
224	? $ctx->[4]($now, $_[0], $level, $format)	248	? $ctx->[4]($now, $_[0], $level, $format)
225	: $fmt \|\|= _format $now, $_[0], $level, $format;	249	: ($fmt \|\|= _format $now, $_[0], $level, $format);
226		250
227	$ctx->[3]($str);	251	$ctx->[3]($str)
		252	or push @ctx, values %{ $ctx->[2] }; # not consumed - propagate
		253	} else {
		254	push @ctx, values %{ $ctx->[2] }; # not masked - propagate
228	}	255	}
229
230	# not masked, not consumed - propagate to parent contexts
231	push @ctx, values %{ $ctx->[2] };
232	}	256	}
233	}	257	}
234	while $ctx = pop @ctx;	258	while $ctx = pop @ctx;
235		259
236	exit 1 if $level <= 1;	260	exit 1 if $level <= 1;
…		…
280	# and later in your program	304	# and later in your program
281	$debug_log->("yo, stuff here") if $debug;	305	$debug_log->("yo, stuff here") if $debug;
282		306
283	$debug and $debug_log->("123");	307	$debug and $debug_log->("123");
284		308
285	Note: currently the enabled var is always true - that will be fixed in a
286	future version :)
287
288	=cut	309	=cut
289		310
290	our %LOGGER;	311	our %LOGGER;
291		312
292	# re-assess logging status for all loggers	313	# re-assess logging status for all loggers
293	sub _reassess {	314	sub _reassess {
		315	local $SIG{__DIE__};
		316	my $die = sub { die };
		317
294	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {	318	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {
295	my ($ctx, $level, $renabled) = @$_;	319	my ($ctx, $level, $renabled) = @$_;
296		320
297	# to detect whether a message would be logged, we # actually	321	# 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	322	# try to log one and die. this isn't fast, but we can be
299	# sure that the logging decision is correct :)	323	# sure that the logging decision is correct :)
300		324
301	$$renabled = !eval {	325	$$renabled = !eval {
302	local $SIG{__DIE__};
303
304	_log $ctx, $level, sub { die };	326	_log $ctx, $level, $die;
305		327
306	1	328	1
307	};	329	};
308
309	$$renabled = 1; # TODO
310	}	330	}
311	}	331	}
312		332
313	sub _logger($;$) {	333	sub _logger {
314	my ($ctx, $level, $renabled) = @_;	334	my ($ctx, $level, $renabled) = @_;
315
316	$renabled \|\|= \my $enabled;
317		335
318	$$renabled = 1;	336	$$renabled = 1;
319		337
320	my $logger = [$ctx, $level, $renabled];	338	my $logger = [$ctx, $level, $renabled];
321		339
…		…
361	timestamp, context, level and string message and formats it in the way	379	timestamp, context, level and string message and formats it in the way
362	it should be logged) and a logging callback (which is responsible for	380	it should be logged) and a logging callback (which is responsible for
363	actually logging the formatted message and telling C<AnyEvent::Log>	381	actually logging the formatted message and telling C<AnyEvent::Log>
364	whether it has consumed the message, or whether it should be propagated).	382	whether it has consumed the message, or whether it should be propagated).
365		383
366	For propagation, a context can have any number of attached I<parent	384	For propagation, a context can have any number of attached I<slave
367	contexts>. Any message that is neither masked by the logging mask nor	385	contexts>. Any message that is neither masked by the logging mask nor
368	masked by the logging callback returning true will be passed to all parent	386	masked by the logging callback returning true will be passed to all slave
369	contexts.	387	contexts.
370		388
371	Each call to a logging function will log the message at most once per	389	Each call to a logging function will log the message at most once per
372	context, so it does not matter (much) if there are cycles or if the	390	context, so it does not matter (much) if there are cycles or if the
373	message can arrive at the same context via multiple paths.	391	message can arrive at the same context via multiple paths.
…		…
377	By default, all logging contexts have an full set of log levels ("all"), a	395	By default, all logging contexts have an full set of log levels ("all"), a
378	disabled logging callback and the default formatting callback.	396	disabled logging callback and the default formatting callback.
379		397
380	Package contexts have the package name as logging title by default.	398	Package contexts have the package name as logging title by default.
381		399
382	They have exactly one parent - the context of the "parent" package. The	400	They have exactly one slave - the context of the "parent" package. The
383	parent package is simply defined to be the package name without the last	401	parent package is simply defined to be the package name without the last
384	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,	402	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
385	and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the	403	and C<AnyEvent> becomes ... C<$AnyEvent::Log::COLLECT> which is the
386	exception of the rule - just like the parent of any package name in	404	exception of the rule - just like the "parent" of any single-component
387	Perl is C<main>, the default parent of any top-level package context is	405	package name in Perl is C<main>, the default slave of any top-level
388	C<AnyEvent::Log::Top>.	406	package context is C<$AnyEvent::Log::COLLECT>.
389		407
390	Since perl packages form only an approximate hierarchy, this parent	408	Since perl packages form only an approximate hierarchy, this slave
391	context can of course be removed.	409	context can of course be removed.
392		410
393	All other (anonymous) contexts have no parents and an empty title by	411	All other (anonymous) contexts have no slaves and an empty title by
394	default.	412	default.
395		413
396	When the module is loaded it creates the default context called	414	When the module is loaded it creates the C<$AnyEvent::Log::LOG> logging
397	C<AnyEvent::Log::Default> (also stored in C<$AnyEvent::Log::Default>),	415	context that simply logs everything via C<warn>, without propagating
398	which simply logs everything to STDERR and doesn't propagate anything
399	anywhere by default. The purpose of the default context is to provide	416	anything anywhere by default. The purpose of this context is to provide
400	a convenient place to override the global logging target or to attach	417	a convenient place to override the global logging target or to attach
401	additional log targets. It's not meant for filtering.	418	additional log targets. It's not meant for filtering.
402		419
403	It then creates the root context called C<AnyEvent::Log::Root> (also	420	It then creates the C<$AnyEvent::Log::FILTER> context whose
404	stored in C<$AnyEvent::Log::Root>) and sets its log level set to all	421	purpose is to suppress all messages with priority higher
405	levels up to the one specified by C<$ENV{PERL_ANYEVENT_VERBOSE}>. It	422	than C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the
406	then attached the default logging context to it. The purpose of the root	423	C<$AnyEvent::Log::LOG> context to it. The purpose of the filter context
407	context is to simply provide filtering according to some global log level.	424	is to simply provide filtering according to some global log level.
408		425
409	Finally it creates the top-level package context called	426	Finally it creates the top-level package context C<$AnyEvent::Log::COLLECT>
410	C<AnyEvent::Log::Top> (also stored in, you might have guessed,	427	and attaches the C<$AnyEvent::Log::FILTER> context to it, but otherwise
411	C<$AnyEvent::Log::Top>) and attached the root context but otherwise leaves
412	it at default config. It's purpose is simply to collect all log messages	428	leaves it at default config. Its purpose is simply to collect all log
413	system-wide.	429	messages system-wide.
414		430
415	These three special contexts can also be referred to by the	431	The hierarchy is then:
416	package/context names C<AE::Log::Default>, C<AE::Log::Root> and
417	C<AE::Log::Top>.
418		432
		433	any package, eventually -> $COLLECT -> $FILTER -> $LOG
		434
419	The effect of all this is that log messages, by default, wander up	435	The effect of all this is that log messages, by default, wander up to the
420	to the root context where log messages with lower priority then	436	C<$AnyEvent::Log::COLLECT> context where all messages normally end up,
		437	from there to C<$AnyEvent::Log::FILTER> where log messages with lower
421	C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered away and then to the	438	priority then C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered out and then
422	AnyEvent::Log::Default context to be logged to STDERR.	439	to the C<$AnyEvent::Log::LOG> context to be passed to C<warn>.
423		440
424	Splitting the top level context into three contexts makes it easy to set	441	This makes it easy to set a global logging level (by modifying $FILTER),
425	a global logging level (by modifying the root context), but still allow	442	but still allow other contexts to send, for example, their debug and trace
426	other contexts to log, for example, their debug and trace messages to the
427	default target despite the global logging level, or to attach additional	443	messages to the $LOG target despite the global logging level, or to attach
428	log targets that log messages, regardless of the global logging level.	444	additional log targets that log messages, regardless of the global logging
		445	level.
429		446
430	It also makes it easy to replace the default STDERR-logger by something	447	It also makes it easy to modify the default warn-logger ($LOG) to
431	that logs to a file, or to attach additional logging targets.	448	something that logs to a file, or to attach additional logging targets
		449	(such as loggign to a file) by attaching it to $FILTER.
432		450
433	=head2 CREATING/FINDING/DESTROYING CONTEXTS	451	=head2 CREATING/FINDING/DESTROYING CONTEXTS
434		452
435	=over 4	453	=over 4
436		454
…		…
458	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"	476	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"
459	}	477	}
460		478
461	=item AnyEvent::Log::reset	479	=item AnyEvent::Log::reset
462		480
463	Deletes all contexts and recreates the default hierarchy, i.e. resets the	481	Resets all package contexts and recreates the default hierarchy if
464	logging subsystem to defaults.	482	necessary, i.e. resets the logging subsystem to defaults, as much as
		483	possible. This process keeps references to contexts held by other parts of
		484	the program intact.
465		485
466	This can be used to implement config-file (re-)loading: before loading a	486	This can be used to implement config-file (re-)loading: before loading a
467	configuration, reset all contexts.	487	configuration, reset all contexts.
468		488
469	=cut	489	=cut
470		490
471	sub reset {	491	sub reset {
472	@$_ = () for values %CTX; # just to be sure - to kill circular logging dependencies	492	# hard to kill complex data structures
473	%CTX = ();	493	# we "recreate" all package loggers and reset the hierarchy
		494	while (my ($k, $v) = each %CTX) {
		495	@$v = ($k, (1 << 10) - 1 - 1, { });
474		496
475	my $default = ctx undef;	497	$v->attach ($k =~ /^(.+)::/ ? $CTX{$1} : $AnyEvent::Log::COLLECT);
476	$default->title ("AnyEvent::Log::Default");	498	}
		499
		500	@$_ = ($_->[0], (1 << 10) - 1 - 1)
		501	for $LOG, $FILTER, $COLLECT;
		502
		503	$LOG->slaves;
		504	$LOG->title ('$AnyEvent::Log::LOG');
477	$default->log_cb (sub {	505	$LOG->log_cb (sub {
478	print STDERR shift;	506	warn shift;
479	0	507	0
480	});	508	});
481	$AnyEvent::Log::Default = $CTX{"AnyEvent::Log::Default"} = $CTX{"AE::Log::Default"} = $default;
482		509
483	my $root = ctx undef;	510	$FILTER->slaves ($LOG);
484	$root->title ("AnyEvent::Log::Root");	511	$FILTER->title ('$AnyEvent::Log::FILTER');
485	$root->level ($AnyEvent::VERBOSE);	512	$FILTER->level ($AnyEvent::VERBOSE);
486	$root->attach ($default);
487	$AnyEvent::Log::Root = $CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $root;
488		513
489	my $top = ctx undef;	514	$COLLECT->slaves ($FILTER);
490	$top->title ("AnyEvent::Log::Top");	515	$COLLECT->title ('$AnyEvent::Log::COLLECT');
491	$top->attach ($root);	516
492	$AnyEvent::Log::Top = $CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $top;	517	_reassess;
493	}	518	}
		519
		520	# create the default logger contexts
		521	$LOG = ctx undef;
		522	$FILTER = ctx undef;
		523	$COLLECT = ctx undef;
494		524
495	AnyEvent::Log::reset;	525	AnyEvent::Log::reset;
496		526
497	# hello, CPAN, please catch me	527	# hello, CPAN, please catch me
498	package AnyEvent::Log::Default;
499	package AE::Log::Default;
500	package AnyEvent::Log::Root;
501	package AE::Log::Root;
502	package AnyEvent::Log::Top;	528	package AnyEvent::Log::LOG;
503	package AE::Log::Top;	529	package AE::Log::LOG;
		530	package AnyEvent::Log::FILTER;
		531	package AE::Log::FILTER;
		532	package AnyEvent::Log::COLLECT;
		533	package AE::Log::COLLECT;
504		534
505	package AnyEvent::Log::Ctx;	535	package AnyEvent::Log::Ctx;
506		536
507	# 0 1 2 3 4	537	# 0 1 2 3 4
508	# [$title, $level, %$parents, &$logcb, &$fmtcb]	538	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
509		539
510	=item $ctx = new AnyEvent::Log::Ctx methodname => param...	540	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
511		541
512	This is a convenience constructor that makes it simpler to construct	542	This is a convenience constructor that makes it simpler to construct
513	anonymous logging contexts.	543	anonymous logging contexts.
…		…
516	name as the key with the value as parameter, unless the value is an	546	name as the key with the value as parameter, unless the value is an
517	arrayref, in which case it calls the method with the contents of the	547	arrayref, in which case it calls the method with the contents of the
518	array. The methods are called in the same order as specified.	548	array. The methods are called in the same order as specified.
519		549
520	Example: create a new logging context and set both the default logging	550	Example: create a new logging context and set both the default logging
521	level, some parent contexts and a logging callback.	551	level, some slave contexts and a logging callback.
522		552
523	$ctx = new AnyEvent::Log::Ctx	553	$ctx = new AnyEvent::Log::Ctx
524	title => "dubious messages",	554	title => "dubious messages",
525	level => "error",	555	level => "error",
526	log_cb => sub { print STDOUT shift; 0 },	556	log_cb => sub { print STDOUT shift; 0 },
527	parents => [$ctx1, $ctx, $ctx2],	557	slaves => [$ctx1, $ctx, $ctx2],
528	;	558	;
529		559
530	=back	560	=back
531		561
532	=cut	562	=cut
…		…
645	AnyEvent::Log::_reassess;	675	AnyEvent::Log::_reassess;
646	}	676	}
647		677
648	=back	678	=back
649		679
650	=head3 PARENT CONTEXTS	680	=head3 SLAVE CONTEXTS
651		681
652	The following methods attach and detach another logging context to a	682	The following methods attach and detach another logging context to a
653	logging context.	683	logging context.
654		684
655	Log messages are propagated to all parent contexts, unless the logging	685	Log messages are propagated to all slave contexts, unless the logging
656	callback consumes the message.	686	callback consumes the message.
657		687
658	=over 4	688	=over 4
659		689
660	=item $ctx->attach ($ctx2[, $ctx3...])	690	=item $ctx->attach ($ctx2[, $ctx3...])
661		691
662	Attaches the given contexts as parents to this context. It is not an error	692	Attaches the given contexts as slaves to this context. It is not an error
663	to add a context twice (the second add will be ignored).	693	to add a context twice (the second add will be ignored).
664		694
665	A context can be specified either as package name or as a context object.	695	A context can be specified either as package name or as a context object.
666		696
667	=item $ctx->detach ($ctx2[, $ctx3...])	697	=item $ctx->detach ($ctx2[, $ctx3...])
668		698
669	Removes the given parents from this context - it's not an error to attempt	699	Removes the given slaves from this context - it's not an error to attempt
670	to remove a context that hasn't been added.	700	to remove a context that hasn't been added.
671		701
672	A context can be specified either as package name or as a context object.	702	A context can be specified either as package name or as a context object.
673		703
674	=item $ctx->parents ($ctx2[, $ctx3...])	704	=item $ctx->slaves ($ctx2[, $ctx3...])
675		705
676	Replaces all parents attached to this context by the ones given.	706	Replaces all slaves attached to this context by the ones given.
677		707
678	=cut	708	=cut
679		709
680	sub attach {	710	sub attach {
681	my $ctx = shift;	711	my $ctx = shift;
…		…
689		719
690	delete $ctx->[2]{$_+0}	720	delete $ctx->[2]{$_+0}
691	for map { AnyEvent::Log::ctx $_ } @_;	721	for map { AnyEvent::Log::ctx $_ } @_;
692	}	722	}
693		723
694	sub parents {	724	sub slaves {
695	undef $_[0][2];	725	undef $_[0][2];
696	&attach;	726	&attach;
697	}	727	}
698		728
699	=back	729	=back
700		730
701	=head3 MESSAGE LOGGING	731	=head3 LOG TARGETS
702		732
703	The following methods configure how the logging context actually does	733	The following methods configure how the logging context actually does
704	the logging (which consists of formatting the message and printing it or	734	the logging (which consists of formatting the message and printing it or
705	whatever it wants to do with it) and also allows you to log messages	735	whatever it wants to do with it).
706	directly to a context, without going via your package context.
707		736
708	=over 4	737	=over 4
709		738
710	=item $ctx->log_cb ($cb->($str))	739	=item $ctx->log_cb ($cb->($str)
711		740
712	Replaces the logging callback on the context (C<undef> disables the	741	Replaces the logging callback on the context (C<undef> disables the
713	logging callback).	742	logging callback).
714		743
715	The logging callback is responsible for handling formatted log messages	744	The logging callback is responsible for handling formatted log messages
716	(see C<fmt_cb> below) - normally simple text strings that end with a	745	(see C<fmt_cb> below) - normally simple text strings that end with a
717	newline (and are possibly multiline themselves).	746	newline (and are possibly multiline themselves).
718		747
719	It also has to return true iff it has consumed the log message, and false	748	It also has to return true iff it has consumed the log message, and false
720	if it hasn't. Consuming a message means that it will not be sent to any	749	if it hasn't. Consuming a message means that it will not be sent to any
721	parent context. When in doubt, return C<0> from your logging callback.	750	slave context. When in doubt, return C<0> from your logging callback.
722		751
723	Example: a very simple logging callback, simply dump the message to STDOUT	752	Example: a very simple logging callback, simply dump the message to STDOUT
724	and do not consume it.	753	and do not consume it.
725		754
726	$ctx->log_cb (sub { print STDERR shift; 0 });	755	$ctx->log_cb (sub { print STDERR shift; 0 });
…		…
734	your program.	763	your program.
735		764
736	$ctx->levels ("debug", "trace");	765	$ctx->levels ("debug", "trace");
737	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages	766	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages
738		767
739	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	768	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $orig_ctx, $level, $message))
740		769
741	Replaces the formatting callback on the context (C<undef> restores the	770	Replaces the formatting callback on the context (C<undef> restores the
742	default formatter).	771	default formatter).
743		772
744	The callback is passed the (possibly fractional) timestamp, the original	773	The callback is passed the (possibly fractional) timestamp, the original
745	logging context, the (numeric) logging level and the raw message string and needs to	774	logging context, the (numeric) logging level and the raw message string
746	return a formatted log message. In most cases this will be a string, but	775	and needs to return a formatted log message. In most cases this will be a
747	it could just as well be an array reference that just stores the values.	776	string, but it could just as well be an array reference that just stores
		777	the values.
		778
		779	If, for some reaosn, you want to use C<caller> to find out more baout the
		780	logger then you should walk up the call stack until you are no longer
		781	inside the C<AnyEvent::Log> package.
748		782
749	Example: format just the raw message, with numeric log level in angle	783	Example: format just the raw message, with numeric log level in angle
750	brackets.	784	brackets.
751		785
752	$ctx->fmt_cb (sub {	786	$ctx->fmt_cb (sub {
…		…
769	"$msg->[3]";	803	"$msg->[3]";
770		804
771	0	805	0
772	});	806	});
773		807
		808	=item $ctx->log_to_file ($path)
		809
		810	Sets the C<log_cb> to log to a file (by appending), unbuffered.
		811
		812	=item $ctx->log_to_path ($path)
		813
		814	Same as C<< ->log_to_file >>, but opens the file for each message. This
		815	is much slower, but allows you to change/move/rename/delete the file at
		816	basically any time.
		817
		818	=item $ctx->log_to_syslog ([$log_flags])
		819
		820	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and all
		821	the others in the obvious way. If specified, then the C<$log_flags> are
		822	simply or'ed onto the priority argument and can contain any C<LOG_xxx>
		823	flags valid for Sys::Syslog::syslog, except for the priority levels.
		824
		825	Note that this function also sets a C<fmt_cb> - the logging part requires
		826	an array reference with [$level, $str] as input.
		827
774	=cut	828	=cut
775		829
776	sub log_cb {	830	sub log_cb {
777	my ($ctx, $cb) = @_;	831	my ($ctx, $cb) = @_;
778		832
…		…
783	my ($ctx, $cb) = @_;	837	my ($ctx, $cb) = @_;
784		838
785	$ctx->[4] = $cb;	839	$ctx->[4] = $cb;
786	}	840	}
787		841
788	=item $ctx->log ($level, $msg[, @params])	842	sub log_to_file {
789		843	my ($ctx, $path) = @_;
790	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
791
792	=item $logger = $ctx->logger ($level[, \$enabled])
793
794	Same as C<AnyEvent::Log::logger>, but uses the given context as log
795	context.
796
797	=cut
798
799	*log = \&AnyEvent::Log::_log;
800	*logger = \&AnyEvent::Log::_logger;
801
802	1;
803
804	=back
805
806	=head1 EXAMPLES
807
808	This section shows some common configurations.
809
810	=over 4
811
812	=item Setting the global logging level.
813
814	Either put PERL_ANYEVENT_VERBOSE=<number> into your environment before
815	running your program, or modify the log level of the root context:
816
817	PERL_ANYEVENT_VERBOSE=5 ./myprog
818
819	$AnyEvent::Log::Root->level ("warn");
820
821	=item Append all messages to a file instead of sending them to STDERR.
822
823	This is affected by the global logging level.
824		844
825	open my $fh, ">>", $path	845	open my $fh, ">>", $path
826	or die "$path: $!";	846	or die "$path: $!";
827		847
828	$AnyEvent::Log::Default->log_cb (sub {	848	$ctx->log_cb (sub {
829	syswrite $fh, shift;	849	syswrite $fh, shift;
830	0	850	0
831	});	851	});
		852	}
		853
		854	sub log_to_file {
		855	my ($ctx, $path) = @_;
		856
		857	$ctx->log_cb (sub {
		858	open my $fh, ">>", $path
		859	or die "$path: $!";
		860
		861	syswrite $fh, shift;
		862	0
		863	});
		864	}
		865
		866	sub log_to_syslog {
		867	my ($ctx, $flags) = @_;
		868
		869	require Sys::Syslog;
		870
		871	$ctx->fmt_cb (sub {
		872	my $str = $_[3];
		873	$str =~ s/\n(?=.)/\n+ /g;
		874
		875	[$_[2], "($_[1][0]) $str"]
		876	});
		877
		878	$ctx->log_cb (sub {
		879	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;
		880
		881	Sys::Syslog::syslog ($flags \| ($lvl - 1), $_)
		882	for split /\n/, $_[0][1];
		883
		884	0
		885	});
		886	}
		887
		888	=back
		889
		890	=head3 MESSAGE LOGGING
		891
		892	These methods allow you to log messages directly to a context, without
		893	going via your package context.
		894
		895	=over 4
		896
		897	=item $ctx->log ($level, $msg[, @params])
		898
		899	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
		900
		901	=item $logger = $ctx->logger ($level[, \$enabled])
		902
		903	Same as C<AnyEvent::Log::logger>, but uses the given context as log
		904	context.
		905
		906	=cut
		907
		908	*log = \&AnyEvent::Log::_log;
		909	*logger = \&AnyEvent::Log::_logger;
		910
		911	1;
		912
		913	=back
		914
		915	=head1 EXAMPLES
		916
		917	This section shows some common configurations.
		918
		919	=over 4
		920
		921	=item Setting the global logging level.
		922
		923	Either put PERL_ANYEVENT_VERBOSE=<number> into your environment before
		924	running your program, or modify the log level of the root context:
		925
		926	PERL_ANYEVENT_VERBOSE=5 ./myprog
		927
		928	$AnyEvent::Log::FILTER->level ("warn");
		929
		930	=item Append all messages to a file instead of sending them to STDERR.
		931
		932	This is affected by the global logging level.
		933
		934	$AnyEvent::Log::LOG->log_to_file ($path); (sub {
832		935
833	=item Write all messages with priority C<error> and higher to a file.	936	=item Write all messages with priority C<error> and higher to a file.
834		937
835	This writes them only when the global logging level allows it, because	938	This writes them only when the global logging level allows it, because
836	it is attached to the default context which is invoked I<after> global	939	it is attached to the default context which is invoked I<after> global
837	filtering.	940	filtering.
838		941
839	open my $fh, ">>", $path	942	$AnyEvent::Log::FILTER->attach
840	or die "$path: $!";	943	new AnyEvent::Log::Ctx log_to_file => $path);
841
842	$AnyEvent::Log::Default->attach (new AnyEvent::Log::Ctx
843	log_cb => sub { syswrite $fh, shift; 0 });
844		944
845	This writes them regardless of the global logging level, because it is	945	This writes them regardless of the global logging level, because it is
846	attached to the toplevel context, which receives all messages I<before>	946	attached to the toplevel context, which receives all messages I<before>
847	the global filtering.	947	the global filtering.
848		948
849	$AnyEvent::Log::Top->attach (new AnyEvent::Log::Ctx	949	$AnyEvent::Log::COLLECT->attach (
850	log_cb => sub { syswrite $fh, shift; 0 });	950	new AnyEvent::Log::Ctx log_to_file => $path);
851		951
852	In both cases, messages are still written to STDOUT.	952	In both cases, messages are still written to STDERR.
853		953
854	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).	954	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
855		955
856	Attach the CyAnyEvent::Log::Default> context to the C<AnyEvent::Debug>	956	Attach the C<$AnyEvent::Log::LOG> context to the C<AnyEvent::Debug>
857	context and increase the C<AnyEvent::Debug> logging level - this simply
858	circumvents the global filtering for trace messages.	957	context - this simply circumvents the global filtering for trace messages.
859		958
860	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;	959	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
861	$debug->attach ($AnyEvent::Log::Default);	960	$debug->attach ($AnyEvent::Log::LOG);
862	$debug->levels ("trace"); # not "level"!
863		961
864	This of course works for any package.	962	This of course works for any package, not just L<AnyEvent::Debug>, but
		963	assumes the log level for AnyEvent::Debug hasn't been changed from the
		964	default.
865		965
866	=back	966	=back
867		967
868	=head1 AUTHOR	968	=head1 AUTHOR
869		969

Diff Legend

-–
+Removed lines
-+
+Added lines
-<
+Changed lines
->
+Changed lines

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents): Revision 1.14 by root, Sat Aug 20 01:49:27 2011 UTC vs. Revision 1.21 by root, Sat Aug 20 22:33:08 2011 UTC

Diff Legend

Comparing AnyEvent/lib/AnyEvent/Log.pm (file contents):
Revision 1.14 by root, Sat Aug 20 01:49:27 2011 UTC vs.
Revision 1.21 by root, Sat Aug 20 22:33:08 2011 UTC