… | |
… | |
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 |
|
|
8 | use AnyEvent; |
|
|
9 | |
|
|
10 | AE::log debug => "hit my knee"; |
|
|
11 | AE::log warn => "it's a bit too hot"; |
|
|
12 | AE::log error => "the flag was false!"; |
|
|
13 | AE::log fatal => "the bit toggled! run!"; |
|
|
14 | |
|
|
15 | # "complex" use |
7 | use AnyEvent::Log; |
16 | use AnyEvent::Log; |
|
|
17 | |
|
|
18 | my $tracer = AnyEvent::Log::logger trace => \$my $trace; |
|
|
19 | |
|
|
20 | $tracer->("i am here") if $trace; |
|
|
21 | $tracer->(sub { "lots of data: " . Dumper $self }) if $trace; |
|
|
22 | |
|
|
23 | # configuration |
|
|
24 | |
|
|
25 | # set logging for this package to maximum |
|
|
26 | AnyEvent::Log::ctx->level ("all"); |
|
|
27 | |
|
|
28 | # set logging globally to anything below debug |
|
|
29 | (AnyEvent::Log::ctx "")->level ("notice"); |
|
|
30 | |
|
|
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); |
8 | |
40 | |
9 | =head1 DESCRIPTION |
41 | =head1 DESCRIPTION |
10 | |
42 | |
11 | This module implements a relatively simple "logging framework". It doesn't |
43 | This module implements a relatively simple "logging framework". It doesn't |
12 | attempt to be "the" logging solution or even "a" logging solution for |
44 | attempt to be "the" logging solution or even "a" logging solution for |
13 | AnyEvent - AnyEvent simply creates logging messages internally, and this |
45 | AnyEvent - AnyEvent simply creates logging messages internally, and this |
14 | module more or less exposes the mechanism, with some extra spiff to allow |
46 | module more or less exposes the mechanism, with some extra spiff to allow |
15 | using it from other modules as well. |
47 | using it from other modules as well. |
16 | |
48 | |
17 | Remember that the default verbosity level is C<0>, so nothing |
49 | Remember that the default verbosity level is C<0>, so nothing will be |
18 | will be logged, ever, unless you set C<$Anyvent::VERBOSE> or |
50 | logged, unless you set C<PERL_ANYEVENT_VERBOSE> to a higher number before |
19 | C<PERL_ANYEVENT_VERBOSE> to a higher number. |
51 | starting your program, or change the logging level at runtime with |
|
|
52 | something like: |
20 | |
53 | |
21 | Possible future extensions are to allow custom log targets (where the |
54 | use AnyEvent; |
22 | level is an object), log filtering based on package, formatting, aliasing |
55 | (AnyEvent::Log::ctx "")->level ("info"); |
23 | or package groups. |
|
|
24 | |
56 | |
|
|
57 | The design goal behind this module was to keep it simple (and small), |
|
|
58 | but make it powerful enough to be potentially useful for any module, and |
|
|
59 | extensive enough for the most common tasks, such as logging to multiple |
|
|
60 | targets, or being able to log into a database. |
|
|
61 | |
25 | =head1 LOG FUNCTIONS |
62 | =head1 LOGGING FUNCTIONS |
26 | |
63 | |
27 | These functions allow you to log messages. They always use the caller's |
64 | These functions allow you to log messages. They always use the caller's |
28 | package as a "logging module/source". Also, The main logging function is |
65 | package as a "logging module/source". Also, the main logging function is |
29 | easily available as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> |
66 | callable as C<AnyEvent::log> or C<AE::log> when the C<AnyEvent> module is |
30 | module is loaded. |
67 | loaded. |
31 | |
68 | |
32 | =over 4 |
69 | =over 4 |
33 | |
70 | |
34 | =cut |
71 | =cut |
35 | |
72 | |
… | |
… | |
37 | |
74 | |
38 | use Carp (); |
75 | use Carp (); |
39 | use POSIX (); |
76 | use POSIX (); |
40 | |
77 | |
41 | use AnyEvent (); BEGIN { AnyEvent::common_sense } |
78 | use AnyEvent (); BEGIN { AnyEvent::common_sense } |
|
|
79 | use AnyEvent::Util (); |
42 | |
80 | |
43 | our ($now_int, $now_str1, $now_str2); |
81 | our ($now_int, $now_str1, $now_str2); |
44 | |
82 | |
45 | # Format Time, not public - yet? |
83 | # Format Time, not public - yet? |
46 | sub ft($) { |
84 | sub ft($) { |
… | |
… | |
51 | if $now_int != $i; |
89 | if $now_int != $i; |
52 | |
90 | |
53 | "$now_str1$f$now_str2" |
91 | "$now_str1$f$now_str2" |
54 | } |
92 | } |
55 | |
93 | |
|
|
94 | our %CTX; # all logging contexts |
|
|
95 | |
|
|
96 | # creates a default package context object for the given package |
|
|
97 | sub _pkg_ctx($) { |
|
|
98 | my $ctx = bless [$_[0], (1 << 10) - 1 - 1, {}], "AnyEvent::Log::Ctx"; |
|
|
99 | |
|
|
100 | # link "parent" package |
|
|
101 | my $pkg = $_[0] =~ /^(.+)::/ ? $1 : "AE::Log::Top"; |
|
|
102 | |
|
|
103 | $pkg = $CTX{$pkg} ||= &_pkg_ctx ($pkg); |
|
|
104 | $ctx->[2]{$pkg+0} = $pkg; |
|
|
105 | |
|
|
106 | $ctx |
|
|
107 | } |
|
|
108 | |
56 | =item AnyEvent::Log::log $level, $msg[, @args] |
109 | =item AnyEvent::Log::log $level, $msg[, @args] |
57 | |
110 | |
58 | Requests logging of the given C<$msg> with the given log level (1..9). |
111 | Requests logging of the given C<$msg> with the given log level (1..9). |
59 | You can also use the following strings as log level: C<fatal> (1), |
112 | You can also use the following strings as log level: C<fatal> (1), |
60 | C<alert> (2), C<critical> (3), C<error> (4), C<warn> (5), C<note> (6), |
113 | C<alert> (2), C<critical> (3), C<error> (4), C<warn> (5), C<note> (6), |
… | |
… | |
66 | C<$msg> is interpreted as an sprintf format string. |
119 | C<$msg> is interpreted as an sprintf format string. |
67 | |
120 | |
68 | The C<$msg> should not end with C<\n>, but may if that is convenient for |
121 | The C<$msg> should not end with C<\n>, but may if that is convenient for |
69 | you. Also, multiline messages are handled properly. |
122 | you. Also, multiline messages are handled properly. |
70 | |
123 | |
71 | In addition, for possible future expansion, C<$msg> must not start with an |
124 | Last not least, C<$msg> might be a code reference, in which case it is |
72 | angle bracket (C<< < >>). |
125 | 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 |
|
|
127 | message in the first place. |
73 | |
128 | |
74 | Whether the given message will be logged depends on the maximum log level |
129 | Whether the given message will be logged depends on the maximum log level |
75 | and the caller's package. |
130 | and the caller's package. |
76 | |
131 | |
77 | Note that you can (and should) call this function as C<AnyEvent::log> or |
132 | Note that you can (and should) call this function as C<AnyEvent::log> or |
78 | C<AE::log>, without C<use>-ing this module if possible, as those functions |
133 | C<AE::log>, without C<use>-ing this module if possible (i.e. you don't |
79 | will laod the logging module on demand only. |
134 | need any additional functionality), as those functions will load the |
|
|
135 | logging module on demand only. They are also much shorter to write. |
|
|
136 | |
|
|
137 | Also, if you optionally generate a lot of debug messages (such as when |
|
|
138 | tracing some code), you should look into using a logger callback and a |
|
|
139 | boolean enabler (see C<logger>, below). |
|
|
140 | |
|
|
141 | Example: log something at error level. |
|
|
142 | |
|
|
143 | AE::log error => "something"; |
|
|
144 | |
|
|
145 | Example: use printf-formatting. |
|
|
146 | |
|
|
147 | AE::log info => "%5d %-10.10s %s", $index, $category, $msg; |
|
|
148 | |
|
|
149 | Example: only generate a costly dump when the message is actually being logged. |
|
|
150 | |
|
|
151 | AE::log debug => sub { require Data::Dump; Data::Dump::dump \%cache }; |
80 | |
152 | |
81 | =cut |
153 | =cut |
82 | |
154 | |
83 | # also allow syslog equivalent names |
155 | # also allow syslog equivalent names |
84 | our %STR2LEVEL = ( |
156 | our %STR2LEVEL = ( |
… | |
… | |
91 | info => 7, |
163 | info => 7, |
92 | debug => 8, |
164 | debug => 8, |
93 | trace => 9, |
165 | trace => 9, |
94 | ); |
166 | ); |
95 | |
167 | |
|
|
168 | sub now () { time } |
|
|
169 | |
|
|
170 | AnyEvent::post_detect { |
|
|
171 | *now = \&AE::now; |
|
|
172 | }; |
|
|
173 | |
96 | our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace); |
174 | our @LEVEL2STR = qw(0 fatal alert crit error warn note info debug trace); |
97 | |
175 | |
|
|
176 | # time, ctx, level, msg |
|
|
177 | sub _format($$$$) { |
|
|
178 | my $ts = ft $_[0]; |
|
|
179 | my $ct = " "; |
|
|
180 | |
|
|
181 | my @res; |
|
|
182 | |
|
|
183 | for (split /\n/, sprintf "%-5s %s: %s", $LEVEL2STR[$_[2]], $_[1][0], $_[3]) { |
|
|
184 | push @res, "$ts$ct$_\n"; |
|
|
185 | $ct = " + "; |
|
|
186 | } |
|
|
187 | |
|
|
188 | join "", @res |
|
|
189 | } |
|
|
190 | |
|
|
191 | sub _log { |
|
|
192 | my ($ctx, $level, $format, @args) = @_; |
|
|
193 | |
|
|
194 | $level = $level > 0 && $level <= 9 |
|
|
195 | ? $level+0 |
|
|
196 | : $STR2LEVEL{$level} || Carp::croak "$level: not a valid logging level, caught"; |
|
|
197 | |
|
|
198 | my $mask = 1 << $level; |
|
|
199 | |
|
|
200 | my (%seen, @ctx, $now, $fmt); |
|
|
201 | |
|
|
202 | do |
|
|
203 | { |
|
|
204 | # skip if masked |
|
|
205 | if ($ctx->[1] & $mask && !$seen{$ctx+0}++) { |
|
|
206 | if ($ctx->[3]) { |
|
|
207 | # logging target found |
|
|
208 | |
|
|
209 | # now get raw message, unless we have it already |
|
|
210 | unless ($now) { |
|
|
211 | $format = $format->() if ref $format; |
|
|
212 | $format = sprintf $format, @args if @args; |
|
|
213 | $format =~ s/\n$//; |
|
|
214 | $now = AE::now; |
|
|
215 | }; |
|
|
216 | |
|
|
217 | # format msg |
|
|
218 | my $str = $ctx->[4] |
|
|
219 | ? $ctx->[4]($now, $_[0], $level, $format) |
|
|
220 | : $fmt ||= _format $now, $_[0], $level, $format; |
|
|
221 | |
|
|
222 | $ctx->[3]($str); |
|
|
223 | } |
|
|
224 | |
|
|
225 | # not masked, not consumed - propagate to parent contexts |
|
|
226 | push @ctx, values %{ $ctx->[2] }; |
|
|
227 | } |
|
|
228 | } |
|
|
229 | while $ctx = pop @ctx; |
|
|
230 | |
|
|
231 | exit 1 if $level <= 1; |
|
|
232 | } |
|
|
233 | |
98 | sub log($$;@) { |
234 | sub log($$;@) { |
99 | my ($targ, $msg, @args) = @_; |
235 | _log |
|
|
236 | $CTX{ (caller)[0] } ||= _pkg_ctx +(caller)[0], |
|
|
237 | @_; |
|
|
238 | } |
100 | |
239 | |
101 | my $level = ref $targ ? die "Can't use reference as logging level (yet)" |
240 | *AnyEvent::log = *AE::log = \&log; |
102 | : $targ > 0 && $targ <= 9 ? $targ+0 |
|
|
103 | : $STR2LEVEL{$targ} || Carp::croak "$targ: not a valid logging level, caught"; |
|
|
104 | |
241 | |
105 | return if $level > $AnyEvent::VERBOSE; |
242 | =item $logger = AnyEvent::Log::logger $level[, \$enabled] |
106 | |
243 | |
107 | my $pkg = (caller)[0]; |
244 | 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 |
|
|
246 | level. C<$logger> is passed a C<$msg> and optional C<@args>, just as with |
|
|
247 | the C<AnyEvent::Log::log> function: |
108 | |
248 | |
109 | $msg = sprintf $msg, @args if @args; |
249 | my $debug_log = AnyEvent::Log::logger "debug"; |
110 | $msg =~ s/\n$//; |
|
|
111 | |
250 | |
112 | # now we have a message, log it |
251 | $debug_log->("debug here"); |
113 | #TODO: could do LOTS of stuff here, and should, at least in some later version |
252 | $debug_log->("%06d emails processed", 12345); |
|
|
253 | $debug_log->(sub { $obj->as_string }); |
114 | |
254 | |
115 | $msg = sprintf "%5s (%s) %s", $LEVEL2STR[$level], $pkg, $msg; |
255 | The idea behind this function is to decide whether to log before actually |
116 | my $pfx = ft AE::now; |
256 | logging - when the C<logger> function is called once, but the returned |
|
|
257 | logger callback often, then this can be a tremendous speed win. |
117 | |
258 | |
118 | for (split /\n/, $msg) { |
259 | Despite this speed advantage, changes in logging configuration will |
119 | printf STDERR "$pfx $_\n"; |
260 | still be reflected by the logger callback, even if configuration changes |
120 | $pfx = "\t"; |
261 | I<after> it was created. |
|
|
262 | |
|
|
263 | To further speed up logging, you can bind a scalar variable to the logger, |
|
|
264 | which contains true if the logger should be called or not - if it is |
|
|
265 | false, calling the logger can be safely skipped. This variable will be |
|
|
266 | updated as long as C<$logger> is alive. |
|
|
267 | |
|
|
268 | Full example: |
|
|
269 | |
|
|
270 | # near the init section |
|
|
271 | use AnyEvent::Log; |
|
|
272 | |
|
|
273 | my $debug_log = AnyEvent:Log::logger debug => \my $debug; |
|
|
274 | |
|
|
275 | # and later in your program |
|
|
276 | $debug_log->("yo, stuff here") if $debug; |
|
|
277 | |
|
|
278 | $debug and $debug_log->("123"); |
|
|
279 | |
|
|
280 | Note: currently the enabled var is always true - that will be fixed in a |
|
|
281 | future version :) |
|
|
282 | |
|
|
283 | =cut |
|
|
284 | |
|
|
285 | our %LOGGER; |
|
|
286 | |
|
|
287 | # re-assess logging status for all loggers |
|
|
288 | sub _reassess { |
|
|
289 | for (@_ ? $LOGGER{$_[0]} : values %LOGGER) { |
|
|
290 | my ($ctx, $level, $renabled) = @$_; |
|
|
291 | |
|
|
292 | # 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 |
|
|
294 | # sure that the logging decision is correct :) |
|
|
295 | |
|
|
296 | $$renabled = !eval { |
|
|
297 | local $SIG{__DIE__}; |
|
|
298 | |
|
|
299 | _log $ctx, $level, sub { die }; |
|
|
300 | |
|
|
301 | 1 |
|
|
302 | }; |
|
|
303 | |
|
|
304 | $$renabled = 1; # TODO |
121 | } |
305 | } |
122 | |
|
|
123 | exit 1 if $level <= 1; |
|
|
124 | } |
306 | } |
125 | |
307 | |
126 | *AnyEvent::log = *AE::log = \&log; |
308 | sub _logger($;$) { |
|
|
309 | my ($ctx, $level, $renabled) = @_; |
127 | |
310 | |
128 | #TODO |
311 | $renabled ||= \my $enabled; |
|
|
312 | |
|
|
313 | $$renabled = 1; |
|
|
314 | |
|
|
315 | my $logger = [$ctx, $level, $renabled]; |
|
|
316 | |
|
|
317 | $LOGGER{$logger+0} = $logger; |
|
|
318 | |
|
|
319 | _reassess $logger+0; |
|
|
320 | |
|
|
321 | my $guard = AnyEvent::Util::guard { |
|
|
322 | # "clean up" |
|
|
323 | delete $LOGGER{$logger+0}; |
|
|
324 | }; |
|
|
325 | |
|
|
326 | sub { |
|
|
327 | $guard if 0; # keep guard alive, but don't cause runtime overhead |
|
|
328 | |
|
|
329 | _log $ctx, $level, @_ |
|
|
330 | if $$renabled; |
|
|
331 | } |
|
|
332 | } |
|
|
333 | |
|
|
334 | sub logger($;$) { |
|
|
335 | _logger |
|
|
336 | $CTX{ (caller)[0] } ||= _pkg_ctx +(caller)[0], |
|
|
337 | @_ |
|
|
338 | } |
129 | |
339 | |
130 | =back |
340 | =back |
131 | |
341 | |
132 | =head1 CONFIGURATION FUNCTIONALITY |
342 | =head1 LOGGING CONTEXTS |
133 | |
343 | |
134 | None, yet, except for C<PERL_ANYEVENT_VERBOSE>, described in the L<AnyEvent> manpage. |
344 | This module associates every log message with a so-called I<logging |
|
|
345 | context>, based on the package of the caller. Every perl package has its |
|
|
346 | own logging context. |
|
|
347 | |
|
|
348 | A logging context has three major responsibilities: filtering, logging and |
|
|
349 | propagating the message. |
|
|
350 | |
|
|
351 | For the first purpose, filtering, each context has a set of logging |
|
|
352 | levels, called the log level mask. Messages not in the set will be ignored |
|
|
353 | by this context (masked). |
|
|
354 | |
|
|
355 | For logging, the context stores a formatting callback (which takes the |
|
|
356 | 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 |
|
|
358 | actually logging the formatted message and telling C<AnyEvent::Log> |
|
|
359 | whether it has consumed the message, or whether it should be propagated). |
|
|
360 | |
|
|
361 | For propagation, a context can have any number of attached I<parent |
|
|
362 | 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 |
|
|
364 | contexts. |
|
|
365 | |
|
|
366 | 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 |
|
|
368 | message can arrive at the same context via multiple paths. |
|
|
369 | |
|
|
370 | =head2 DEFAULTS |
|
|
371 | |
|
|
372 | By default, all logging contexts have an full set of log levels ("all"), a |
|
|
373 | disabled logging callback and the default formatting callback. |
|
|
374 | |
|
|
375 | Package contexts have the package name as logging title by default. |
|
|
376 | |
|
|
377 | They have exactly one parent - the context of the "parent" package. The |
|
|
378 | 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>, |
|
|
380 | and C<AnyEvent> becomes ... C<AnyEvent::Log::Top> which is the |
|
|
381 | exception of the rule - just like the parent of any package name in |
|
|
382 | Perl is C<main>, the default parent of any top-level package context is |
|
|
383 | C<AnyEvent::Log::Top>. |
|
|
384 | |
|
|
385 | Since perl packages form only an approximate hierarchy, this parent |
|
|
386 | context can of course be removed. |
|
|
387 | |
|
|
388 | All other (anonymous) contexts have no parents and an empty title by |
|
|
389 | default. |
|
|
390 | |
|
|
391 | When the module is loaded it creates the default context called |
|
|
392 | C<AnyEvent::Log::Default> (also stored in C<$AnyEvent::Log::Default>), |
|
|
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 |
|
|
395 | a convenient place to override the global logging target or to attach |
|
|
396 | additional log targets. It's not meant for filtering. |
|
|
397 | |
|
|
398 | It then creates the root context called C<AnyEvent::Log::Root> (also |
|
|
399 | stored in C<$AnyEvent::Log::Root>) and sets its log level set to all |
|
|
400 | levels up to the one specified by C<$ENV{PERL_ANYEVENT_VERBOSE}>. It |
|
|
401 | then attached the default logging context to it. The purpose of the root |
|
|
402 | context is to simply provide filtering according to some global log level. |
|
|
403 | |
|
|
404 | Finally it creates the top-level package context called |
|
|
405 | C<AnyEvent::Log::Top> (also stored in, you might have guessed, |
|
|
406 | C<$AnyEvent::Log::Top>) and attached the root context but otherwise leaves |
|
|
407 | it at default config. It's purpose is simply to collect all log messages |
|
|
408 | system-wide. |
|
|
409 | |
|
|
410 | These three special contexts can also be referred to by the |
|
|
411 | package/context names C<AE::Log::Default>, C<AE::Log::Root> and |
|
|
412 | C<AE::Log::Top>. |
|
|
413 | |
|
|
414 | The effect of all this is that log messages, by default, wander up |
|
|
415 | to the root context where log messages with lower priority then |
|
|
416 | C<$ENV{PERL_ANYEVENT_VERBOSE}> will be filtered away and then to the |
|
|
417 | AnyEvent::Log::Default context to be logged to STDERR. |
|
|
418 | |
|
|
419 | Splitting the top level context into three contexts makes it easy to set |
|
|
420 | a global logging level (by modifying the root context), but still allow |
|
|
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 |
|
|
423 | log targets that log messages, regardless of the global logging level. |
|
|
424 | |
|
|
425 | It also makes it easy to replace the default STDERR-logger by something |
|
|
426 | that logs to a file, or to attach additional logging targets. |
|
|
427 | |
|
|
428 | =head2 CREATING/FINDING/DESTROYING CONTEXTS |
135 | |
429 | |
136 | =over 4 |
430 | =over 4 |
137 | |
431 | |
|
|
432 | =item $ctx = AnyEvent::Log::ctx [$pkg] |
|
|
433 | |
|
|
434 | This function creates or returns a logging context (which is an object). |
|
|
435 | |
|
|
436 | If a package name is given, then the context for that packlage is |
|
|
437 | returned. If it is called without any arguments, then the context for the |
|
|
438 | callers package is returned (i.e. the same context as a C<AE::log> call |
|
|
439 | would use). |
|
|
440 | |
|
|
441 | If C<undef> is given, then it creates a new anonymous context that is not |
|
|
442 | tied to any package and is destroyed when no longer referenced. |
|
|
443 | |
138 | =cut |
444 | =cut |
|
|
445 | |
|
|
446 | sub ctx(;$) { |
|
|
447 | my $pkg = @_ ? shift : (caller)[0]; |
|
|
448 | |
|
|
449 | ref $pkg |
|
|
450 | ? $pkg |
|
|
451 | : defined $pkg |
|
|
452 | ? $CTX{$pkg} ||= AnyEvent::Log::_pkg_ctx $pkg |
|
|
453 | : bless [undef, (1 << 10) - 1 - 1], "AnyEvent::Log::Ctx" |
|
|
454 | } |
|
|
455 | |
|
|
456 | =item AnyEvent::Log::reset |
|
|
457 | |
|
|
458 | Deletes all contexts and recreates the default hierarchy, i.e. resets the |
|
|
459 | logging subsystem to defaults. |
|
|
460 | |
|
|
461 | This can be used to implement config-file (re-)loading: before loading a |
|
|
462 | configuration, reset all contexts. |
|
|
463 | |
|
|
464 | =cut |
|
|
465 | |
|
|
466 | sub reset { |
|
|
467 | @$_ = () for values %CTX; # just to be sure - to kill circular logging dependencies |
|
|
468 | %CTX = (); |
|
|
469 | |
|
|
470 | my $default = ctx undef; |
|
|
471 | $default->title ("AnyEvent::Log::Default"); |
|
|
472 | $default->log_cb (sub { |
|
|
473 | print STDERR shift; |
|
|
474 | 0 |
|
|
475 | }); |
|
|
476 | $AnyEvent::Log::Default = $CTX{"AnyEvent::Log::Default"} = $CTX{"AE::Log::Default"} = $default; |
|
|
477 | |
|
|
478 | my $root = ctx undef; |
|
|
479 | $root->title ("AnyEvent::Log::Root"); |
|
|
480 | $root->level ($AnyEvent::VERBOSE); |
|
|
481 | $root->attach ($default); |
|
|
482 | $AnyEvent::Log::Root = $CTX{"AnyEvent::Log::Root"} = $CTX{"AE::Log::Root"} = $root; |
|
|
483 | |
|
|
484 | my $top = ctx undef; |
|
|
485 | $top->title ("AnyEvent::Log::Top"); |
|
|
486 | $top->attach ($root); |
|
|
487 | $AnyEvent::Log::Top = $CTX{"AnyEvent::Log::Top"} = $CTX{"AE::Log::Top"} = $top; |
|
|
488 | } |
|
|
489 | |
|
|
490 | AnyEvent::Log::reset; |
|
|
491 | |
|
|
492 | # hello, CPAN, please catch me |
|
|
493 | package AnyEvent::Log::Default; |
|
|
494 | package AE::Log::Default; |
|
|
495 | package AnyEvent::Log::Root; |
|
|
496 | package AE::Log::Root; |
|
|
497 | package AnyEvent::Log::Top; |
|
|
498 | package AE::Log::Top; |
|
|
499 | |
|
|
500 | package AnyEvent::Log::Ctx; |
|
|
501 | |
|
|
502 | # 0 1 2 3 4 |
|
|
503 | # [$title, $level, %$parents, &$logcb, &$fmtcb] |
|
|
504 | |
|
|
505 | =item $ctx = new AnyEvent::Log::Ctx methodname => param... |
|
|
506 | |
|
|
507 | This is a convenience constructor that makes it simpler to construct |
|
|
508 | anonymous logging contexts. |
|
|
509 | |
|
|
510 | Each key-value pair results in an invocation of the method of the same |
|
|
511 | 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 |
|
|
513 | array. The methods are called in the same order as specified. |
|
|
514 | |
|
|
515 | Example: create a new logging context and set both the default logging |
|
|
516 | level, some parent contexts and a logging callback. |
|
|
517 | |
|
|
518 | $ctx = new AnyEvent::Log::Ctx |
|
|
519 | title => "dubious messages", |
|
|
520 | level => "error", |
|
|
521 | log_cb => sub { print STDOUT shift; 0 }, |
|
|
522 | parents => [$ctx1, $ctx, $ctx2], |
|
|
523 | ; |
|
|
524 | |
|
|
525 | =back |
|
|
526 | |
|
|
527 | =cut |
|
|
528 | |
|
|
529 | sub new { |
|
|
530 | my $class = shift; |
|
|
531 | |
|
|
532 | my $ctx = AnyEvent::Log::ctx undef; |
|
|
533 | |
|
|
534 | while (@_) { |
|
|
535 | my ($k, $v) = splice @_, 0, 2; |
|
|
536 | $ctx->$k (ref $v eq "ARRAY" ? @$v : $v); |
|
|
537 | } |
|
|
538 | |
|
|
539 | bless $ctx, $class # do we really support subclassing, hmm? |
|
|
540 | } |
|
|
541 | |
|
|
542 | |
|
|
543 | =head2 CONFIGURING A LOG CONTEXT |
|
|
544 | |
|
|
545 | The following methods can be used to configure the logging context. |
|
|
546 | |
|
|
547 | =over 4 |
|
|
548 | |
|
|
549 | =item $ctx->title ([$new_title]) |
|
|
550 | |
|
|
551 | Returns the title of the logging context - this is the package name, for |
|
|
552 | package contexts, and a user defined string for all others. |
|
|
553 | |
|
|
554 | If C<$new_title> is given, then it replaces the package name or title. |
|
|
555 | |
|
|
556 | =cut |
|
|
557 | |
|
|
558 | sub title { |
|
|
559 | $_[0][0] = $_[1] if @_ > 1; |
|
|
560 | $_[0][0] |
|
|
561 | } |
|
|
562 | |
|
|
563 | =back |
|
|
564 | |
|
|
565 | =head3 LOGGING LEVELS |
|
|
566 | |
|
|
567 | The following methods deal with the logging level set associated with the |
|
|
568 | log context. |
|
|
569 | |
|
|
570 | The most common method to use is probably C<< $ctx->level ($level) >>, |
|
|
571 | which configures the specified and any higher priority levels. |
|
|
572 | |
|
|
573 | All functions which accept a list of levels also accept the special string |
|
|
574 | C<all> which expands to all logging levels. |
|
|
575 | |
|
|
576 | =over 4 |
|
|
577 | |
|
|
578 | =item $ctx->levels ($level[, $level...) |
|
|
579 | |
|
|
580 | Enables logging for the given levels and disables it for all others. |
|
|
581 | |
|
|
582 | =item $ctx->level ($level) |
|
|
583 | |
|
|
584 | Enables logging for the given level and all lower level (higher priority) |
|
|
585 | ones. In addition to normal logging levels, specifying a level of C<0> or |
|
|
586 | C<off> disables all logging for this level. |
|
|
587 | |
|
|
588 | Example: log warnings, errors and higher priority messages. |
|
|
589 | |
|
|
590 | $ctx->level ("warn"); |
|
|
591 | $ctx->level (5); # same thing, just numeric |
|
|
592 | |
|
|
593 | =item $ctx->enable ($level[, $level...]) |
|
|
594 | |
|
|
595 | Enables logging for the given levels, leaving all others unchanged. |
|
|
596 | |
|
|
597 | =item $ctx->disable ($level[, $level...]) |
|
|
598 | |
|
|
599 | Disables logging for the given levels, leaving all others unchanged. |
|
|
600 | |
|
|
601 | =cut |
|
|
602 | |
|
|
603 | sub _lvl_lst { |
|
|
604 | map { |
|
|
605 | $_ > 0 && $_ <= 9 ? $_+0 |
|
|
606 | : $_ eq "all" ? (1 .. 9) |
|
|
607 | : $STR2LEVEL{$_} || Carp::croak "$_: not a valid logging level, caught" |
|
|
608 | } @_ |
|
|
609 | } |
|
|
610 | |
|
|
611 | our $NOP_CB = sub { 0 }; |
|
|
612 | |
|
|
613 | sub levels { |
|
|
614 | my $ctx = shift; |
|
|
615 | $ctx->[1] = 0; |
|
|
616 | $ctx->[1] |= 1 << $_ |
|
|
617 | for &_lvl_lst; |
|
|
618 | AnyEvent::Log::_reassess; |
|
|
619 | } |
|
|
620 | |
|
|
621 | sub level { |
|
|
622 | my $ctx = shift; |
|
|
623 | my $lvl = $_[0] =~ /^(?:0|off|none)$/ ? 0 : (_lvl_lst $_[0])[-1]; |
|
|
624 | |
|
|
625 | $ctx->[1] = ((1 << $lvl) - 1) << 1; |
|
|
626 | AnyEvent::Log::_reassess; |
|
|
627 | } |
|
|
628 | |
|
|
629 | sub enable { |
|
|
630 | my $ctx = shift; |
|
|
631 | $ctx->[1] |= 1 << $_ |
|
|
632 | for &_lvl_lst; |
|
|
633 | AnyEvent::Log::_reassess; |
|
|
634 | } |
|
|
635 | |
|
|
636 | sub disable { |
|
|
637 | my $ctx = shift; |
|
|
638 | $ctx->[1] &= ~(1 << $_) |
|
|
639 | for &_lvl_lst; |
|
|
640 | AnyEvent::Log::_reassess; |
|
|
641 | } |
|
|
642 | |
|
|
643 | =back |
|
|
644 | |
|
|
645 | =head3 PARENT CONTEXTS |
|
|
646 | |
|
|
647 | The following methods attach and detach another logging context to a |
|
|
648 | logging context. |
|
|
649 | |
|
|
650 | Log messages are propagated to all parent contexts, unless the logging |
|
|
651 | callback consumes the message. |
|
|
652 | |
|
|
653 | =over 4 |
|
|
654 | |
|
|
655 | =item $ctx->attach ($ctx2[, $ctx3...]) |
|
|
656 | |
|
|
657 | Attaches the given contexts as parents to this context. It is not an error |
|
|
658 | to add a context twice (the second add will be ignored). |
|
|
659 | |
|
|
660 | A context can be specified either as package name or as a context object. |
|
|
661 | |
|
|
662 | =item $ctx->detach ($ctx2[, $ctx3...]) |
|
|
663 | |
|
|
664 | Removes the given parents from this context - it's not an error to attempt |
|
|
665 | to remove a context that hasn't been added. |
|
|
666 | |
|
|
667 | A context can be specified either as package name or as a context object. |
|
|
668 | |
|
|
669 | =item $ctx->parents ($ctx2[, $ctx3...]) |
|
|
670 | |
|
|
671 | Replaces all parents attached to this context by the ones given. |
|
|
672 | |
|
|
673 | =cut |
|
|
674 | |
|
|
675 | sub attach { |
|
|
676 | my $ctx = shift; |
|
|
677 | |
|
|
678 | $ctx->[2]{$_+0} = $_ |
|
|
679 | for map { AnyEvent::Log::ctx $_ } @_; |
|
|
680 | } |
|
|
681 | |
|
|
682 | sub detach { |
|
|
683 | my $ctx = shift; |
|
|
684 | |
|
|
685 | delete $ctx->[2]{$_+0} |
|
|
686 | for map { AnyEvent::Log::ctx $_ } @_; |
|
|
687 | } |
|
|
688 | |
|
|
689 | sub parents { |
|
|
690 | undef $_[0][2]; |
|
|
691 | &attach; |
|
|
692 | } |
|
|
693 | |
|
|
694 | =back |
|
|
695 | |
|
|
696 | =head3 MESSAGE LOGGING |
|
|
697 | |
|
|
698 | The following methods configure how the logging context actually does |
|
|
699 | 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 |
|
|
701 | directly to a context, without going via your package context. |
|
|
702 | |
|
|
703 | =over 4 |
|
|
704 | |
|
|
705 | =item $ctx->log_cb ($cb->($str)) |
|
|
706 | |
|
|
707 | Replaces the logging callback on the context (C<undef> disables the |
|
|
708 | logging callback). |
|
|
709 | |
|
|
710 | The logging callback is responsible for handling formatted log messages |
|
|
711 | (see C<fmt_cb> below) - normally simple text strings that end with a |
|
|
712 | newline (and are possibly multiline themselves). |
|
|
713 | |
|
|
714 | 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 |
|
|
716 | parent context. When in doubt, return C<0> from your logging callback. |
|
|
717 | |
|
|
718 | Example: a very simple logging callback, simply dump the message to STDOUT |
|
|
719 | and do not consume it. |
|
|
720 | |
|
|
721 | $ctx->log_cb (sub { print STDERR shift; 0 }); |
|
|
722 | |
|
|
723 | You can filter messages by having a log callback that simply returns C<1> |
|
|
724 | and does not do anything with the message, but this counts as "message |
|
|
725 | being logged" and might not be very efficient. |
|
|
726 | |
|
|
727 | Example: propagate all messages except for log levels "debug" and |
|
|
728 | "trace". The messages will still be generated, though, which can slow down |
|
|
729 | your program. |
|
|
730 | |
|
|
731 | $ctx->levels ("debug", "trace"); |
|
|
732 | $ctx->log_cb (sub { 1 }); # do not log, but eat debug and trace messages |
|
|
733 | |
|
|
734 | =item $ctx->fmt_cb ($fmt_cb->($timestamp, $ctx, $level, $message)) |
|
|
735 | |
|
|
736 | Replaces the formatting callback on the context (C<undef> restores the |
|
|
737 | default formatter). |
|
|
738 | |
|
|
739 | 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 |
|
|
741 | return a formatted log message. In most cases this will be a string, but |
|
|
742 | it could just as well be an array reference that just stores the values. |
|
|
743 | |
|
|
744 | Example: format just the raw message, with numeric log level in angle |
|
|
745 | brackets. |
|
|
746 | |
|
|
747 | $ctx->fmt_cb (sub { |
|
|
748 | my ($time, $ctx, $lvl, $msg) = @_; |
|
|
749 | |
|
|
750 | "<$lvl>$msg\n" |
|
|
751 | }); |
|
|
752 | |
|
|
753 | Example: return an array reference with just the log values, and use |
|
|
754 | C<PApp::SQL::sql_exec> to store the emssage in a database. |
|
|
755 | |
|
|
756 | $ctx->fmt_cb (sub { \@_ }); |
|
|
757 | $ctx->log_cb (sub { |
|
|
758 | my ($msg) = @_; |
|
|
759 | |
|
|
760 | sql_exec "insert into log (when, subsys, prio, msg) values (?, ?, ?, ?)", |
|
|
761 | $msg->[0] + 0, |
|
|
762 | "$msg->[1]", |
|
|
763 | $msg->[2] + 0, |
|
|
764 | "$msg->[3]"; |
|
|
765 | |
|
|
766 | 0 |
|
|
767 | }); |
|
|
768 | |
|
|
769 | =cut |
|
|
770 | |
|
|
771 | sub log_cb { |
|
|
772 | my ($ctx, $cb) = @_; |
|
|
773 | |
|
|
774 | $ctx->[3] = $cb; |
|
|
775 | } |
|
|
776 | |
|
|
777 | sub fmt_cb { |
|
|
778 | my ($ctx, $cb) = @_; |
|
|
779 | |
|
|
780 | $ctx->[4] = $cb; |
|
|
781 | } |
|
|
782 | |
|
|
783 | =item $ctx->log ($level, $msg[, @params]) |
|
|
784 | |
|
|
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; |
139 | |
796 | |
140 | 1; |
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 | |
|
|
820 | open my $fh, ">>", $path |
|
|
821 | or die "$path: $!"; |
|
|
822 | |
|
|
823 | $AnyEvent::Log::Default->log_cb (sub { |
|
|
824 | syswrite $fh, shift; |
|
|
825 | 0 |
|
|
826 | }); |
|
|
827 | |
|
|
828 | =item Write all messages with priority C<error> and higher to a file. |
|
|
829 | |
|
|
830 | 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 |
|
|
832 | filtering. |
|
|
833 | |
|
|
834 | open my $fh, ">>", $path |
|
|
835 | or die "$path: $!"; |
|
|
836 | |
|
|
837 | $AnyEvent::Log::Default->attach (new AnyEvent::Log::Ctx |
|
|
838 | log_cb => sub { syswrite $fh, shift; 0 }); |
|
|
839 | |
|
|
840 | This writes them regardless of the global logging level, because it is |
|
|
841 | attached to the toplevel context, which receives all messages I<before> |
|
|
842 | the global filtering. |
|
|
843 | |
|
|
844 | $AnyEvent::Log::Top->attach (new AnyEvent::Log::Ctx |
|
|
845 | log_cb => sub { syswrite $fh, shift; 0 }); |
|
|
846 | |
|
|
847 | In both cases, messages are still written to STDOUT. |
|
|
848 | |
|
|
849 | =item Write trace messages (only) from L<AnyEvent::Debug> to the default logging target(s). |
|
|
850 | |
|
|
851 | Attach the CyAnyEvent::Log::Default> 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. |
|
|
854 | |
|
|
855 | my $debug = AnyEvent::Debug->AnyEvent::Log::ctx; |
|
|
856 | $debug->attach ($AnyEvent::Log::Default); |
|
|
857 | $debug->levels ("trace"); # not "level"! |
|
|
858 | |
|
|
859 | This of course works for any package. |
141 | |
860 | |
142 | =back |
861 | =back |
143 | |
862 | |
144 | =head1 AUTHOR |
863 | =head1 AUTHOR |
145 | |
864 | |