[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 1.24 by root, Sun Aug 21 03:24:59 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 use:
		8
8	use AnyEvent;	9	use AnyEvent;
9		10
10	AE::log debug => "hit my knee";	11	AE::log debug => "hit my knee";
11	AE::log warn => "it's a bit too hot";	12	AE::log warn => "it's a bit too hot";
12	AE::log error => "the flag was false!";	13	AE::log error => "the flag was false!";
13	AE::log fatal => "the bit toggled! run!";	14	AE::log fatal => "the bit toggled! run!"; # never returns
14		15
15	# "complex" use	16	# "complex" use (for speed sensitive code):
		17
16	use AnyEvent::Log;	18	use AnyEvent::Log;
17		19
18	my $tracer = AnyEvent::Log::logger trace => \$my $trace;	20	my $tracer = AnyEvent::Log::logger trace => \$my $trace;
19		21
20	$tracer->("i am here") if $trace;	22	$tracer->("i am here") if $trace;
21	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;	23	$tracer->(sub { "lots of data: " . Dumper $self }) if $trace;
22		24
23	# configuration	25	# configuration:
24		26
25	# set logging for this package to maximum	27	# set logging for the current package to errors and higher only
26	AnyEvent::Log::ctx->level ("all");	28	AnyEvent::Log::ctx->level ("error");
27		29
28	# set logging globally to anything below debug	30	# set logging level to suppress anything below "notice"
29	(AnyEvent::Log::ctx "")->level ("notice");	31	$AnyEvent::Log::FILTER->level ("notice");
		32
		33	# send all critical and higher priority messages to syslog,
		34	# regardless of (most) other settings
		35	$AnyEvent::Log::COLLECT->attach (new AnyEvent::Log::Ctx
		36	level => "critical",
		37	log_to_syslog => 0,
		38	);
30		39
31	# see also EXAMPLES, below	40	# 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		41
41	=head1 DESCRIPTION	42	=head1 DESCRIPTION
42		43
43	This module implements a relatively simple "logging framework". It doesn't	44	This module implements a relatively simple "logging framework". It doesn't
44	attempt to be "the" logging solution or even "a" logging solution for	45	attempt to be "the" logging solution or even "a" logging solution for
45	AnyEvent - AnyEvent simply creates logging messages internally, and this	46	AnyEvent - AnyEvent simply creates logging messages internally, and this
46	module more or less exposes the mechanism, with some extra spiff to allow	47	module more or less exposes the mechanism, with some extra spiff to allow
47	using it from other modules as well.	48	using it from other modules as well.
48		49
49	Remember that the default verbosity level is C<0>, so nothing will be	50	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	51	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	52	before starting your program, or change the logging level at runtime with
52	something like:	53	something like:
53		54
54	use AnyEvent;	55	use AnyEvent::Log;
55	(AnyEvent::Log::ctx "")->level ("info");	56	AnyEvent::Log::FILTER->level ("info");
56		57
57	The design goal behind this module was to keep it simple (and small),	58	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	59	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	60	extensive enough for the most common tasks, such as logging to multiple
60	targets, or being able to log into a database.	61	targets, or being able to log into a database.
61		62
62	The amount of documentation might indicate otherwise, but the module is	63	The amount of documentation might indicate otherwise, but the module is
63	still just 240 lines or so.	64	still just below 300 lines of code.
		65
		66	=head1 LOGGING LEVELS
		67
		68	Logging levels in this module range from C<1> (highest priority) to C<9>
		69	(lowest priority). Note that the lowest numerical value is the highest
		70	priority, so when this document says "higher priority" it means "lower
		71	numerical value".
		72
		73	Instead of specifying levels by name you can also specify them by aliases:
		74
		75	LVL NAME SYSLOG PERL NOTE
		76	1 fatal emerg exit aborts program!
		77	2 alert
		78	3 critical crit
		79	4 error err die
		80	5 warn warning
		81	6 note notice
		82	7 info
		83	8 debug
		84	9 trace
		85
		86	As you can see, some logging levels have multiple aliases - the first one
		87	is the "official" name, the second one the "syslog" name (if it differs)
		88	and the third one the "perl" name, suggesting that you log C<die> messages
		89	at C<error> priority.
		90
		91	You can normally only log a single message at highest priority level
		92	(C<1>, C<fatal>), because logging a fatal message will also quit the
		93	program - so use it sparingly :)
		94
		95	Some methods also offer some extra levels, such as C<0>, C<off>, C<none>
		96	or C<all> - these are only valid in the methods they are documented for.
64		97
65	=head1 LOGGING FUNCTIONS	98	=head1 LOGGING FUNCTIONS
66		99
67	These functions allow you to log messages. They always use the caller's	100	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	101	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	102	callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is
70	loaded.	103	loaded.
71		104
72	=over 4	105	=over 4
73		106
…		…
80		113
81	use AnyEvent (); BEGIN { AnyEvent::common_sense }	114	use AnyEvent (); BEGIN { AnyEvent::common_sense }
82	use AnyEvent::Util ();	115	use AnyEvent::Util ();
83		116
84	our $VERSION = $AnyEvent::VERSION;	117	our $VERSION = $AnyEvent::VERSION;
		118
		119	our ($COLLECT, $FILTER, $LOG);
85		120
86	our ($now_int, $now_str1, $now_str2);	121	our ($now_int, $now_str1, $now_str2);
87		122
88	# Format Time, not public - yet?	123	# Format Time, not public - yet?
89	sub ft($) {	124	sub ft($) {
…		…
94	if $now_int != $i;	129	if $now_int != $i;
95		130
96	"$now_str1$f$now_str2"	131	"$now_str1$f$now_str2"
97	}	132	}
98		133
99	our %CTX; # all logging contexts	134	our %CTX; # all package contexts
100		135
101	# creates a default package context object for the given package	136	# creates a default package context object for the given package
102	sub _pkg_ctx($) {	137	sub _pkg_ctx($) {
103	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";	138	my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx";
104		139
105	# link "parent" package	140	# link "parent" package
106	my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "AE::Log::Top";	141	my $parent = $_[0] =~ /^(.+)::/
		142	? $CTX{$1} \|\|= &_pkg_ctx ("$1")
		143	: $COLLECT;
107		144
108	$pkg = $CTX{$pkg} \|\|= &_pkg_ctx ($pkg);
109	$ctx->[2]{$pkg+0} = $pkg;	145	$ctx->[2]{$parent+0} = $parent;
110		146
111	$ctx	147	$ctx
112	}	148	}
113		149
114	=item AnyEvent::Log::log $level, $msg[, @args]	150	=item AnyEvent::Log::log $level, $msg[, @args]
115		151
116	Requests logging of the given C<$msg> with the given log level (1..9).	152	Requests logging of the given C<$msg> with the given log level, and
117	You can also use the following strings as log level: C<fatal> (1),	153	returns true if the message was logged I<somewhere>.
118	C<alert> (2), C<critical> (3), C<error> (4), C<warn> (5), C<note> (6),
119	C<info> (7), C<debug> (8), C<trace> (9).
120		154
121	For C<fatal> log levels, the program will abort.	155	For C<fatal> log levels, the program will abort.
122		156
123	If only a C<$msg> is given, it is logged as-is. With extra C<@args>, the	157	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.	158	C<$msg> is interpreted as an sprintf format string.
…		…
130	supposed to return the message. It will be called only then the message	164	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	165	actually gets logged, which is useful if it is costly to create the
132	message in the first place.	166	message in the first place.
133		167
134	Whether the given message will be logged depends on the maximum log level	168	Whether the given message will be logged depends on the maximum log level
135	and the caller's package.	169	and the caller's package. The return value can be used to ensure that
		170	messages or not "lost" - for example, when L<AnyEvent::Debug> detects a
		171	runtime error it tries to log it at C<die> level, but if that message is
		172	lost it simply uses warn.
136		173
137	Note that you can (and should) call this function as C<AnyEvent::log> or	174	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	175	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	176	need any additional functionality), as those functions will load the
140	logging module on demand only. They are also much shorter to write.	177	logging module on demand only. They are also much shorter to write.
…		…
157		194
158	=cut	195	=cut
159		196
160	# also allow syslog equivalent names	197	# also allow syslog equivalent names
161	our %STR2LEVEL = (	198	our %STR2LEVEL = (
162	fatal => 1, emerg => 1,	199	fatal => 1, emerg => 1, exit => 1,
163	alert => 2,	200	alert => 2,
164	critical => 3, crit => 3,	201	critical => 3, crit => 3,
165	error => 4, err => 4,	202	error => 4, err => 4, die => 4,
166	warn => 5, warning => 5,	203	warn => 5, warning => 5,
167	note => 6, notice => 6,	204	note => 6, notice => 6,
168	info => 7,	205	info => 7,
169	debug => 8,	206	debug => 8,
170	trace => 9,	207	trace => 9,
…		…
200	? $level+0	237	? $level+0
201	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";	238	: $STR2LEVEL{$level} \|\| Carp::croak "$level: not a valid logging level, caught";
202		239
203	my $mask = 1 << $level;	240	my $mask = 1 << $level;
204		241
205	my (%seen, @ctx, $now, $fmt);	242	my ($success, %seen, @ctx, $now, $fmt);
206		243
207	do	244	do
208	{	245	{
209	# skip if masked	246	# skip if masked
210	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {	247	if ($ctx->[1] & $mask && !$seen{$ctx+0}++) {
…		…
220	};	257	};
221		258
222	# format msg	259	# format msg
223	my $str = $ctx->[4]	260	my $str = $ctx->[4]
224	? $ctx->[4]($now, $_[0], $level, $format)	261	? $ctx->[4]($now, $_[0], $level, $format)
225	: $fmt \|\|= _format $now, $_[0], $level, $format;	262	: ($fmt \|\|= _format $now, $_[0], $level, $format);
226		263
		264	$success = 1;
		265
227	$ctx->[3]($str);	266	$ctx->[3]($str)
		267	or push @ctx, values %{ $ctx->[2] }; # not consumed - propagate
		268	} else {
		269	push @ctx, values %{ $ctx->[2] }; # not masked - propagate
228	}	270	}
229
230	# not masked, not consumed - propagate to parent contexts
231	push @ctx, values %{ $ctx->[2] };
232	}	271	}
233	}	272	}
234	while $ctx = pop @ctx;	273	while $ctx = pop @ctx;
235		274
236	exit 1 if $level <= 1;	275	exit 1 if $level <= 1;
		276
		277	$success
237	}	278	}
238		279
239	sub log($$;@) {	280	sub log($$;@) {
240	_log	281	_log
241	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],	282	$CTX{ (caller)[0] } \|\|= _pkg_ctx +(caller)[0],
…		…
245	AnyEvent::log = AE::log = \&log;	286	AnyEvent::log = AE::log = \&log;
246		287
247	=item $logger = AnyEvent::Log::logger $level[, \$enabled]	288	=item $logger = AnyEvent::Log::logger $level[, \$enabled]
248		289
249	Creates a code reference that, when called, acts as if the	290	Creates a code reference that, when called, acts as if the
250	C<AnyEvent::Log::log> function was called at this point with the givne	291	C<AnyEvent::Log::log> function was called at this point with the given
251	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with	292	level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with
252	the C<AnyEvent::Log::log> function:	293	the C<AnyEvent::Log::log> function:
253		294
254	my $debug_log = AnyEvent::Log::logger "debug";	295	my $debug_log = AnyEvent::Log::logger "debug";
255		296
…		…
280	# and later in your program	321	# and later in your program
281	$debug_log->("yo, stuff here") if $debug;	322	$debug_log->("yo, stuff here") if $debug;
282		323
283	$debug and $debug_log->("123");	324	$debug and $debug_log->("123");
284		325
285	Note: currently the enabled var is always true - that will be fixed in a
286	future version :)
287
288	=cut	326	=cut
289		327
290	our %LOGGER;	328	our %LOGGER;
291		329
292	# re-assess logging status for all loggers	330	# re-assess logging status for all loggers
293	sub _reassess {	331	sub _reassess {
		332	local $SIG{__DIE__};
		333	my $die = sub { die };
		334
294	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {	335	for (@_ ? $LOGGER{$_[0]} : values %LOGGER) {
295	my ($ctx, $level, $renabled) = @$_;	336	my ($ctx, $level, $renabled) = @$_;
296		337
297	# to detect whether a message would be logged, we # actually	338	# 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	339	# try to log one and die. this isn't fast, but we can be
299	# sure that the logging decision is correct :)	340	# sure that the logging decision is correct :)
300		341
301	$$renabled = !eval {	342	$$renabled = !eval {
302	local $SIG{__DIE__};
303
304	_log $ctx, $level, sub { die };	343	_log $ctx, $level, $die;
305		344
306	1	345	1
307	};	346	};
308
309	$$renabled = 1; # TODO
310	}	347	}
311	}	348	}
312		349
313	sub _logger {	350	sub _logger {
314	my ($ctx, $level, $renabled) = @_;	351	my ($ctx, $level, $renabled) = @_;
…		…
359	timestamp, context, level and string message and formats it in the way	396	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	397	it should be logged) and a logging callback (which is responsible for
361	actually logging the formatted message and telling C<AnyEvent::Log>	398	actually logging the formatted message and telling C<AnyEvent::Log>
362	whether it has consumed the message, or whether it should be propagated).	399	whether it has consumed the message, or whether it should be propagated).
363		400
364	For propagation, a context can have any number of attached I<parent	401	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	402	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	403	masked by the logging callback returning true will be passed to all slave
367	contexts.	404	contexts.
368		405
369	Each call to a logging function will log the message at most once per	406	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	407	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.	408	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	412	By default, all logging contexts have an full set of log levels ("all"), a
376	disabled logging callback and the default formatting callback.	413	disabled logging callback and the default formatting callback.
377		414
378	Package contexts have the package name as logging title by default.	415	Package contexts have the package name as logging title by default.
379		416
380	They have exactly one parent - the context of the "parent" package. The	417	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	418	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>,	419	component, i.e. C<AnyEvent::Debug::Wrapped> becomes C<AnyEvent::Debug>,
383	and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the	420	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	421	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	422	package name in Perl is C<main>, the default slave of any top-level
386	C<AnyEvent::Log::Top>.	423	package context is C<$AnyEvent::Log::COLLECT>.
387		424
388	Since perl packages form only an approximate hierarchy, this parent	425	Since perl packages form only an approximate hierarchy, this slave
389	context can of course be removed.	426	context can of course be removed.
390		427
391	All other (anonymous) contexts have no parents and an empty title by	428	All other (anonymous) contexts have no slaves and an empty title by
392	default.	429	default.
393		430
394	When the module is loaded it creates the default context called	431	When the module is loaded it creates the C<$AnyEvent::Log::LOG> logging
395	C<AnyEvent::Log::Default> (also stored in C<$AnyEvent::Log::Default>),	432	context that simply logs everything via C<warn>, without propagating
396	which simply logs everything via C<warn> and doesn't propagate anything
397	anywhere by default. The purpose of the default context is to provide	433	anything anywhere by default. The purpose of this context is to provide
398	a convenient place to override the global logging target or to attach	434	a convenient place to override the global logging target or to attach
399	additional log targets. It's not meant for filtering.	435	additional log targets. It's not meant for filtering.
400		436
401	It then creates the root context called C<AnyEvent::Log::Root> (also	437	It then creates the C<$AnyEvent::Log::FILTER> context whose
402	stored in C<$AnyEvent::Log::Root>) and sets its log level set to all	438	purpose is to suppress all messages with priority higher
403	levels up to the one specified by C<$ENV{PERL_ANYEVENT_VERBOSE}>. It	439	than C<$ENV{PERL_ANYEVENT_VERBOSE}>. It then attached the
404	then attached the default logging context to it. The purpose of the root	440	C<$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.	441	is to simply provide filtering according to some global log level.
406		442
407	Finally it creates the top-level package context called	443	Finally it creates the top-level package context C<$AnyEvent::Log::COLLECT>
408	C<AnyEvent::Log::Top> (also stored in, you might have guessed,	444	and attaches the C<$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	445	leaves it at default config. Its purpose is simply to collect all log
411	system-wide.	446	messages system-wide.
412		447
413	These three special contexts can also be referred to by the	448	The hierarchy is then:
414	package/context names C<AE::Log::Default>, C<AE::Log::Root> and
415	C<AE::Log::Top>.
416		449
		450	any package, eventually -> $COLLECT -> $FILTER -> $LOG
		451
417	The effect of all this is that log messages, by default, wander up	452	The effect of all this is that log messages, by default, wander up to the
418	to the root context where log messages with lower priority then	453	C<$AnyEvent::Log::COLLECT> context where all messages normally end up,
		454	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	455	priority then C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered out and then
420	AnyEvent::Log::Default context to be passed to C<warn>.	456	to the C<$AnyEvent::Log::LOG> context to be passed to C<warn>.
421		457
422	Splitting the top level context into three contexts makes it easy to set	458	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	459	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	460	messages to the $LOG target despite the global logging level, or to attach
426	log targets that log messages, regardless of the global logging level.	461	additional log targets that log messages, regardless of the global logging
		462	level.
427		463
428	It also makes it easy to replace the default warn-logger by something that	464	It also makes it easy to modify the default warn-logger ($LOG) to
429	logs to a file, or to attach additional logging targets.	465	something that logs to a file, or to attach additional logging targets
		466	(such as loggign to a file) by attaching it to $FILTER.
430		467
431	=head2 CREATING/FINDING/DESTROYING CONTEXTS	468	=head2 CREATING/FINDING/DESTROYING CONTEXTS
432		469
433	=over 4	470	=over 4
434		471
…		…
456	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"	493	: bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx"
457	}	494	}
458		495
459	=item AnyEvent::Log::reset	496	=item AnyEvent::Log::reset
460		497
461	Resets all package contexts contexts and recreates the default hierarchy	498	Resets all package contexts and recreates the default hierarchy if
462	if necessary, i.e. resets the logging subsystem to defaults.	499	necessary, i.e. resets the logging subsystem to defaults, as much as
		500	possible. This process keeps references to contexts held by other parts of
		501	the program intact.
463		502
464	This can be used to implement config-file (re-)loading: before loading a	503	This can be used to implement config-file (re-)loading: before loading a
465	configuration, reset all contexts.	504	configuration, reset all contexts.
466		505
467	Note that this currently destroys all logger callbacks - bug me if you
468	need this fixed :)
469
470	=cut	506	=cut
471		507
472	sub reset {	508	sub reset {
473	# hard to kill complex data structures	509	# hard to kill complex data structures
474	# we recreate all package loggers and reset the hierarchy	510	# we "recreate" all package loggers and reset the hierarchy
475	while (my ($k, $v) = each %CTX) {	511	while (my ($k, $v) = each %CTX) {
476	@$v = ($k, (1 << 10) - 1 - 1, { });	512	@$v = ($k, (1 << 10) - 1 - 1, { });
477		513
478	my $pkg = $k =~ /^(.+)::/ ? $1 : "AE::Log::Top";	514	$v->attach ($k =~ /^(.+)::/ ? $CTX{$1} : $AnyEvent::Log::COLLECT);
479	$v->attach ($CTX{$pkg});
480	}	515	}
481		516
482	$AnyEvent::Log::Default->parents;	517	@$_ = ($_->[0], (1 << 10) - 1 - 1)
483	$AnyEvent::Log::Default->title ("AnyEvent::Log::Default");	518	for $LOG, $FILTER, $COLLECT;
484	$AnyEvent::Log::Default->log_cb (sub {	519
		520	$LOG->slaves;
		521	$LOG->title ('$AnyEvent::Log::LOG');
		522	$LOG->log_cb (sub {
485	warn shift;	523	warn shift;
486	0	524	0
487	});	525	});
488	$CTX{"AnyEvent::Log::Default"} = $CTX{"AE::Log::Default"} = $AnyEvent::Log::Default;
489		526
490	$AnyEvent::Log::Root->parents ($AnyEvent::Log::Default);	527	$FILTER->slaves ($LOG);
491	$AnyEvent::Log::Root->title ("AnyEvent::Log::Root");	528	$FILTER->title ('$AnyEvent::Log::FILTER');
492	$AnyEvent::Log::Root->level ($AnyEvent::VERBOSE);	529	$FILTER->level ($AnyEvent::VERBOSE);
493	$CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $AnyEvent::Log::Root;
494		530
495	$AnyEvent::Log::Top->parents ($AnyEvent::Log::Root);	531	$COLLECT->slaves ($FILTER);
496	$AnyEvent::Log::Top->title ("AnyEvent::Log::Top");	532	$COLLECT->title ('$AnyEvent::Log::COLLECT');
497	$CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $AnyEvent::Log::Top;
498		533
499	_reassess;	534	_reassess;
500	}	535	}
501		536
502	# create the default logger contexts	537	# create the default logger contexts
503	$AnyEvent::Log::Default = ctx undef;	538	$LOG = ctx undef;
504	$AnyEvent::Log::Root = ctx undef;	539	$FILTER = ctx undef;
505	$AnyEvent::Log::Top = ctx undef;	540	$COLLECT = ctx undef;
506		541
507	AnyEvent::Log::reset;	542	AnyEvent::Log::reset;
508		543
509	# hello, CPAN, please catch me	544	# hello, CPAN, please catch me
510	package AnyEvent::Log::Default;
511	package AE::Log::Default;
512	package AnyEvent::Log::Root;
513	package AE::Log::Root;
514	package AnyEvent::Log::Top;	545	package AnyEvent::Log::LOG;
515	package AE::Log::Top;	546	package AE::Log::LOG;
		547	package AnyEvent::Log::FILTER;
		548	package AE::Log::FILTER;
		549	package AnyEvent::Log::COLLECT;
		550	package AE::Log::COLLECT;
516		551
517	package AnyEvent::Log::Ctx;	552	package AnyEvent::Log::Ctx;
518		553
519	# 0 1 2 3 4	554	# 0 1 2 3 4
520	# [$title, $level, %$parents, &$logcb, &$fmtcb]	555	# [$title, $level, %$slaves, &$logcb, &$fmtcb]
521		556
522	=item $ctx = new AnyEvent::Log::Ctx methodname => param...	557	=item $ctx = new AnyEvent::Log::Ctx methodname => param...
523		558
524	This is a convenience constructor that makes it simpler to construct	559	This is a convenience constructor that makes it simpler to construct
525	anonymous logging contexts.	560	anonymous logging contexts.
…		…
528	name as the key with the value as parameter, unless the value is an	563	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	564	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.	565	array. The methods are called in the same order as specified.
531		566
532	Example: create a new logging context and set both the default logging	567	Example: create a new logging context and set both the default logging
533	level, some parent contexts and a logging callback.	568	level, some slave contexts and a logging callback.
534		569
535	$ctx = new AnyEvent::Log::Ctx	570	$ctx = new AnyEvent::Log::Ctx
536	title => "dubious messages",	571	title => "dubious messages",
537	level => "error",	572	level => "error",
538	log_cb => sub { print STDOUT shift; 0 },	573	log_cb => sub { print STDOUT shift; 0 },
539	parents => [$ctx1, $ctx, $ctx2],	574	slaves => [$ctx1, $ctx, $ctx2],
540	;	575	;
541		576
542	=back	577	=back
543		578
544	=cut	579	=cut
…		…
657	AnyEvent::Log::_reassess;	692	AnyEvent::Log::_reassess;
658	}	693	}
659		694
660	=back	695	=back
661		696
662	=head3 PARENT CONTEXTS	697	=head3 SLAVE CONTEXTS
663		698
664	The following methods attach and detach another logging context to a	699	The following methods attach and detach another logging context to a
665	logging context.	700	logging context.
666		701
667	Log messages are propagated to all parent contexts, unless the logging	702	Log messages are propagated to all slave contexts, unless the logging
668	callback consumes the message.	703	callback consumes the message.
669		704
670	=over 4	705	=over 4
671		706
672	=item $ctx->attach ($ctx2[, $ctx3...])	707	=item $ctx->attach ($ctx2[, $ctx3...])
673		708
674	Attaches the given contexts as parents to this context. It is not an error	709	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).	710	to add a context twice (the second add will be ignored).
676		711
677	A context can be specified either as package name or as a context object.	712	A context can be specified either as package name or as a context object.
678		713
679	=item $ctx->detach ($ctx2[, $ctx3...])	714	=item $ctx->detach ($ctx2[, $ctx3...])
680		715
681	Removes the given parents from this context - it's not an error to attempt	716	Removes the given slaves from this context - it's not an error to attempt
682	to remove a context that hasn't been added.	717	to remove a context that hasn't been added.
683		718
684	A context can be specified either as package name or as a context object.	719	A context can be specified either as package name or as a context object.
685		720
686	=item $ctx->parents ($ctx2[, $ctx3...])	721	=item $ctx->slaves ($ctx2[, $ctx3...])
687		722
688	Replaces all parents attached to this context by the ones given.	723	Replaces all slaves attached to this context by the ones given.
689		724
690	=cut	725	=cut
691		726
692	sub attach {	727	sub attach {
693	my $ctx = shift;	728	my $ctx = shift;
…		…
701		736
702	delete $ctx->[2]{$_+0}	737	delete $ctx->[2]{$_+0}
703	for map { AnyEvent::Log::ctx $_ } @_;	738	for map { AnyEvent::Log::ctx $_ } @_;
704	}	739	}
705		740
706	sub parents {	741	sub slaves {
707	undef $_[0][2];	742	undef $_[0][2];
708	&attach;	743	&attach;
709	}	744	}
710		745
711	=back	746	=back
712		747
713	=head3 MESSAGE LOGGING	748	=head3 LOG TARGETS
714		749
715	The following methods configure how the logging context actually does	750	The following methods configure how the logging context actually does
716	the logging (which consists of formatting the message and printing it or	751	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	752	whatever it wants to do with it).
718	directly to a context, without going via your package context.
719		753
720	=over 4	754	=over 4
721		755
722	=item $ctx->log_cb ($cb->($str))	756	=item $ctx->log_cb ($cb->($str)
723		757
724	Replaces the logging callback on the context (C<undef> disables the	758	Replaces the logging callback on the context (C<undef> disables the
725	logging callback).	759	logging callback).
726		760
727	The logging callback is responsible for handling formatted log messages	761	The logging callback is responsible for handling formatted log messages
728	(see C<fmt_cb> below) - normally simple text strings that end with a	762	(see C<fmt_cb> below) - normally simple text strings that end with a
729	newline (and are possibly multiline themselves).	763	newline (and are possibly multiline themselves).
730		764
731	It also has to return true iff it has consumed the log message, and false	765	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	766	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.	767	slave context. When in doubt, return C<0> from your logging callback.
734		768
735	Example: a very simple logging callback, simply dump the message to STDOUT	769	Example: a very simple logging callback, simply dump the message to STDOUT
736	and do not consume it.	770	and do not consume it.
737		771
738	$ctx->log_cb (sub { print STDERR shift; 0 });	772	$ctx->log_cb (sub { print STDERR shift; 0 });
…		…
746	your program.	780	your program.
747		781
748	$ctx->levels ("debug", "trace");	782	$ctx->levels ("debug", "trace");
749	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages	783	$ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages
750		784
751	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message))	785	=item $ctx->fmt_cb ($fmt_cb->($timestamp, $orig_ctx, $level, $message))
752		786
753	Replaces the formatting callback on the context (C<undef> restores the	787	Replaces the formatting callback on the context (C<undef> restores the
754	default formatter).	788	default formatter).
755		789
756	The callback is passed the (possibly fractional) timestamp, the original	790	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	791	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	792	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.	793	string, but it could just as well be an array reference that just stores
		794	the values.
		795
		796	If, for some reaosn, you want to use C<caller> to find out more baout the
		797	logger then you should walk up the call stack until you are no longer
		798	inside the C<AnyEvent::Log> package.
760		799
761	Example: format just the raw message, with numeric log level in angle	800	Example: format just the raw message, with numeric log level in angle
762	brackets.	801	brackets.
763		802
764	$ctx->fmt_cb (sub {	803	$ctx->fmt_cb (sub {
…		…
781	"$msg->[3]";	820	"$msg->[3]";
782		821
783	0	822	0
784	});	823	});
785		824
		825	=item $ctx->log_to_file ($path)
		826
		827	Sets the C<log_cb> to log to a file (by appending), unbuffered.
		828
		829	=item $ctx->log_to_path ($path)
		830
		831	Same as C<< ->log_to_file >>, but opens the file for each message. This
		832	is much slower, but allows you to change/move/rename/delete the file at
		833	basically any time.
		834
		835	=item $ctx->log_to_syslog ([$log_flags])
		836
		837	Logs all messages via L<Sys::Syslog>, mapping C<trace> to C<debug> and all
		838	the others in the obvious way. If specified, then the C<$log_flags> are
		839	simply or'ed onto the priority argument and can contain any C<LOG_xxx>
		840	flags valid for Sys::Syslog::syslog, except for the priority levels.
		841
		842	Note that this function also sets a C<fmt_cb> - the logging part requires
		843	an array reference with [$level, $str] as input.
		844
786	=cut	845	=cut
787		846
788	sub log_cb {	847	sub log_cb {
789	my ($ctx, $cb) = @_;	848	my ($ctx, $cb) = @_;
790		849
…		…
795	my ($ctx, $cb) = @_;	854	my ($ctx, $cb) = @_;
796		855
797	$ctx->[4] = $cb;	856	$ctx->[4] = $cb;
798	}	857	}
799		858
800	=item $ctx->log ($level, $msg[, @params])	859	sub log_to_file {
801		860	my ($ctx, $path) = @_;
802	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
803
804	=item $logger = $ctx->logger ($level[, \$enabled])
805
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		861
837	open my $fh, ">>", $path	862	open my $fh, ">>", $path
838	or die "$path: $!";	863	or die "$path: $!";
839		864
840	$AnyEvent::Log::Default->log_cb (sub {	865	$ctx->log_cb (sub {
841	syswrite $fh, shift;	866	syswrite $fh, shift;
842	0	867	0
843	});	868	});
		869	}
		870
		871	sub log_to_file {
		872	my ($ctx, $path) = @_;
		873
		874	$ctx->log_cb (sub {
		875	open my $fh, ">>", $path
		876	or die "$path: $!";
		877
		878	syswrite $fh, shift;
		879	0
		880	});
		881	}
		882
		883	sub log_to_syslog {
		884	my ($ctx, $flags) = @_;
		885
		886	require Sys::Syslog;
		887
		888	$ctx->fmt_cb (sub {
		889	my $str = $_[3];
		890	$str =~ s/\n(?=.)/\n+ /g;
		891
		892	[$_[2], "($_[1][0]) $str"]
		893	});
		894
		895	$ctx->log_cb (sub {
		896	my $lvl = $_[0][0] < 9 ? $_[0][0] : 8;
		897
		898	Sys::Syslog::syslog ($flags \| ($lvl - 1), $_)
		899	for split /\n/, $_[0][1];
		900
		901	0
		902	});
		903	}
		904
		905	=back
		906
		907	=head3 MESSAGE LOGGING
		908
		909	These methods allow you to log messages directly to a context, without
		910	going via your package context.
		911
		912	=over 4
		913
		914	=item $ctx->log ($level, $msg[, @params])
		915
		916	Same as C<AnyEvent::Log::log>, but uses the given context as log context.
		917
		918	=item $logger = $ctx->logger ($level[, \$enabled])
		919
		920	Same as C<AnyEvent::Log::logger>, but uses the given context as log
		921	context.
		922
		923	=cut
		924
		925	*log = \&AnyEvent::Log::_log;
		926	*logger = \&AnyEvent::Log::_logger;
		927
		928	1;
		929
		930	=back
		931
		932	=head1 EXAMPLES
		933
		934	This section shows some common configurations.
		935
		936	=over 4
		937
		938	=item Setting the global logging level.
		939
		940	Either put PERL_ANYEVENT_VERBOSE=<number> into your environment before
		941	running your program, or modify the log level of the root context:
		942
		943	PERL_ANYEVENT_VERBOSE=5 ./myprog
		944
		945	$AnyEvent::Log::FILTER->level ("warn");
		946
		947	=item Append all messages to a file instead of sending them to STDERR.
		948
		949	This is affected by the global logging level.
		950
		951	$AnyEvent::Log::LOG->log_to_file ($path); (sub {
844		952
845	=item Write all messages with priority C<error> and higher to a file.	953	=item Write all messages with priority C<error> and higher to a file.
846		954
847	This writes them only when the global logging level allows it, because	955	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	956	it is attached to the default context which is invoked I<after> global
849	filtering.	957	filtering.
850		958
851	open my $fh, ">>", $path	959	$AnyEvent::Log::FILTER->attach
852	or die "$path: $!";	960	new AnyEvent::Log::Ctx log_to_file => $path);
853
854	$AnyEvent::Log::Default->attach (new AnyEvent::Log::Ctx
855	log_cb => sub { syswrite $fh, shift; 0 });
856		961
857	This writes them regardless of the global logging level, because it is	962	This writes them regardless of the global logging level, because it is
858	attached to the toplevel context, which receives all messages I<before>	963	attached to the toplevel context, which receives all messages I<before>
859	the global filtering.	964	the global filtering.
860		965
861	$AnyEvent::Log::Top->attach (new AnyEvent::Log::Ctx	966	$AnyEvent::Log::COLLECT->attach (
862	log_cb => sub { syswrite $fh, shift; 0 });	967	new AnyEvent::Log::Ctx log_to_file => $path);
863		968
864	In both cases, messages are still written to STDOUT.	969	In both cases, messages are still written to STDERR.
865		970
866	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).	971	=item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s).
867		972
868	Attach the CyAnyEvent::Log::Default> context to the C<AnyEvent::Debug>	973	Attach the C<$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.	974	context - this simply circumvents the global filtering for trace messages.
871		975
872	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;	976	my $debug = AnyEvent::Debug->AnyEvent::Log::ctx;
873	$debug->attach ($AnyEvent::Log::Default);	977	$debug->attach ($AnyEvent::Log::LOG);
874	$debug->levels ("trace"); # not "level"!
875		978
876	This of course works for any package.	979	This of course works for any package, not just L<AnyEvent::Debug>, but
		980	assumes the log level for AnyEvent::Debug hasn't been changed from the
		981	default.
877		982
878	=back	983	=back
879		984
880	=head1 AUTHOR	985	=head1 AUTHOR
881		986

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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 1.24 by root, Sun Aug 21 03:24:59 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 1.24 by root, Sun Aug 21 03:24:59 2011 UTC