1Log::Handler::Examples(U3s)er Contributed Perl DocumentatLioogn::Handler::Examples(3)
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6 Log::Handler::Examples - Examples.
7
9 Quite simple
10
11 use Log::Handler;
12
13 my $log = Log::Handler->new();
14 $log->add( screen => \%options );
15
16 Create a application wide logger
17
18 my $log = Log::Handler->create_logger("myapp");
19 $log->add( screen => \%options );
20
21 Once created you can use the application logger in all modules of your
22 project:
23
24 package MyApp;
25 use Log::Handler;
26
27 my $log = Log::Handler->create_logger("myapp");
28 $log->add( screen => \%options );
29
30 package MyApp::Admin;
31 use Log::Handler;
32
33 my $log = Log::Handler->get_logger("myapp");
34 $log->info("message");
35
37 use Log::Handler;
38
39 my $log = Log::Handler->new();
40
41 $log->add( dbi => \%options );
42 $log->add( email => \%options );
43 $log->add( file => \%options );
44 $log->add( forward => \%options );
45 $log->add( screen => \%options );
46 $log->add( socket => \%options );
47
48 This is the same like
49
50 $log->add( "Log::Handler::Output::DBI" => \%options );
51 $log->add( "Log::Handler::Output::Email" => \%options );
52 $log->add( "Log::Handler::Output::File" => \%options );
53 $log->add( "Log::Handler::Output::Forward" => \%options );
54 $log->add( "Log::Handler::Output::Screen" => \%options );
55 $log->add( "Log::Handler::Output::Socket" => \%options );
56
58 Quite simple
59 use Log::Handler;
60
61 my $log = Log::Handler->new();
62
63 $log->config(config => "logger.conf");
64
65 $log->reload(config => "logger.conf");
66
67 Reload on HUP
68 use Log::Handler;
69
70 my $log = Log::Handler->new();
71
72 $log->config(config => "logger.conf");
73
74 $SIG{HUP} = sub {
75 unless ($log->reload(config => "logger.conf")) {
76 warn "unable to reload configuration";
77 warn $log->errstr;
78 }
79 };
80
81 Validate first
82 It's possible to make a configuration check before you reload:
83
84 $log->validate(config => "logger.conf")
85 or warn $log->errstr;
86
88 use Log::Handler;
89
90 my $log = Log::Handler->new();
91
92 $log->add(
93 dbi => {
94 database => "database",
95 driver => "mysql",
96 host => "127.0.0.1",
97 port => 3306,
98 user => "user",
99 password => "password",
100 table => "messages",
101 columns => [ qw/level ctime cdate pid hostname caller progname mtime message/ ],
102 values => [ qw/%level %time %date %pid %hostname %caller %progname %mtime %message/ ],
103 maxlevel => "error",
104 minlevel => "emergency"
105 newline => 0,
106 message_pattern => "%L %T %D %P %H %C %S %t %m",
107 }
108 );
109
110 $log->error("log an error");
111
112 Or with "dbname"
113
114 $log->add(
115 dbi => {
116 dbname => "database",
117 driver => "Pg",
118 host => "127.0.0.1",
119 port => 5432,
120 user => "user",
121 password => "password",
122 table => "messages",
123 columns => [ qw/level ctime cdate pid hostname caller progname mtime message/ ],
124 values => [ qw/%level %time %date %pid %hostname %caller %progname %mtime %message/ ],
125 maxlevel => "error",
126 minlevel => "emergency"
127 newline => 0,
128 message_pattern => "%L %T %D %P %H %C %S %t %m",
129 }
130 );
131
132 Or with "data_source"
133
134 $log->add(
135 dbi => {
136 data_source => "dbi:SQLite:dbname=database.sqlite",
137 table => "messages",
138 columns => [ qw/level ctime cdate pid hostname caller progname mtime message/ ],
139 values => [ qw/%level %time %date %pid %hostname %caller %progname %mtime %message/ ],
140 maxlevel => "error",
141 minlevel => "emergency"
142 newline => 0,
143 message_pattern => "%L %T %D %P %H %C %S %t %m",
144 }
145 );
146
148 use Log::Handler;
149
150 my $log = Log::Handler->new();
151
152 $log->add(
153 email => {
154 host => "mx.bar.example",
155 hello => "EHLO my.domain.example",
156 timeout => 30,
157 from => "bar@foo.example",
158 to => "foo@bar.example",
159 subject => "your subject",
160 buffer => 0,
161 maxlevel => "emergency",
162 minlevel => "emergency",
163 message_pattern => '%L',
164 }
165 );
166
167 $log->emergency("log an emergency issue");
168
170 use Log::Handler;
171
172 my $log = Log::Handler->new();
173
174 $log->add(
175 sendmail => {
176 from => "bar@foo.example",
177 to => "foo@bar.example",
178 subject => "your subject",
179 maxlevel => "error",
180 minlevel => "error",
181 message_pattern => '%L',
182 }
183 );
184
185 $log->emergency("message");
186
188 use Log::Handler;
189
190 my $log = Log::Handler->new();
191
192 $log->add(
193 file => {
194 filename => "file1.log",
195 maxlevel => 7,
196 minlevel => 0
197 }
198 );
199
200 $log->error("log an error");
201
203 use Log::Handler;
204
205 my $log = Log::Handler->new();
206
207 $log->add(
208 forward => {
209 forward_to => \&my_func,
210 message_pattern => [ qw/%L %T %P %H %C %S %t/ ],
211 message_layout => "%m",
212 maxlevel => "info",
213 }
214 );
215
216 $log->info("log a information");
217
218 sub my_func {
219 my $params = shift;
220 print Dumper($params);
221 }
222
224 use Log::Handler;
225
226 my $log = Log::Handler->new();
227
228 $log->add(
229 screen => {
230 log_to => "STDERR",
231 maxlevel => "info",
232 }
233 );
234
235 $log->info("log to the screen");
236
238 use Log::Handler;
239
240 my $log = Log::Handler->new();
241
242 $log->add(
243 socket => {
244 peeraddr => "127.0.0.1",
245 peerport => 44444,
246 maxlevel => "info",
247 die_on_errors => 0,
248 }
249 );
250
251 while ( 1 ) {
252 $log->info("test")
253 or warn "unable to send message: ", $log->errstr;
254 sleep 1;
255 }
256
257 SIMPLE SOCKET SERVER (TCP)
258 use strict;
259 use warnings;
260 use IO::Socket::INET;
261 use Log::Handler::Output::File;
262
263 my $sock = IO::Socket::INET->new(
264 LocalAddr => "127.0.0.1",
265 LocalPort => 44444,
266 Listen => 2,
267 ) or die $!;
268
269 my $file = Log::Handler::Output::File->new(
270 filename => "file.log",
271 fileopen => 1,
272 reopen => 1,
273 );
274
275 while ( 1 ) {
276 $file->log(message => "waiting for next connection\n");
277
278 while (my $request = $sock->accept) {
279 my $ipaddr = sprintf("%-15s", $request->peerhost);
280 while (my $message = <$request>) {
281 $file->log(message => "$ipaddr - $message");
282 }
283 }
284 }
285
287 use Log::Handler;
288
289 my $log = Log::Handler->new();
290
291 $log->add(
292 file => {
293 filename => "common.log",
294 maxlevel => 6,
295 minlevel => 5,
296 }
297 );
298
299 $log->add(
300 file => {
301 filename => "error.log",
302 maxlevel => 4,
303 minlevel => 0,
304 }
305 );
306
307 $log->add(
308 email => {
309 host => "mx.bar.example",
310 hello => "EHLO my.domain.example",
311 timeout => 120,
312 from => "bar@foo.example",
313 to => "foo@bar.example",
314 subject => "your subject",
315 buffer => 0,
316 maxlevel => 0,
317 }
318 );
319
320 # log to common.log
321 $log->info("this is a info message");
322
323 # log to error.log
324 $log->warning("this is a warning");
325
326 # log to error.log and to foo@bar.example
327 $log->emergency("this is a emergency message");
328
330 my $log = Log::Handler->new();
331
332 $log->add(
333 screen => {
334 maxlevel => 6,
335 filter_message => {
336 match1 => "foo",
337 match2 => "bar",
338 match3 => "baz",
339 condition => "(match1 && match2) && !match3"
340 }
341 }
342 );
343
344 $log->info("foo");
345 $log->info("foo bar");
346 $log->info("foo baz");
347
348 FILTER CALLER
349 This example shows you how it's possilbe to debug messages only from a
350 special namespace.
351
352 my $log = Log::Handler->new();
353
354 $log->add(
355 file => {
356 filename => "file1.log",
357 maxlevel => "warning",
358 }
359 );
360
361 $log->add(
362 screen => {
363 maxlevel => "debug",
364 message_layout => "message from %p - %m",
365 filter_caller => qr/^Foo::Bar\z/,
366 }
367 );
368
369 $log->warning("a warning here");
370
371 package Foo::Bar;
372 $log->info("an info here");
373 1;
374
375 ANOTHER FILTER
376 filter_message => "as string"
377
378 filter_message => qr/as regexp/
379
380 filter_message => sub { shift->{message} =~ /as code ref/ }
381
382 # or with conditions
383
384 filter_message => {
385 match1 => "as string",
386 match2 => qr/as regexp/,
387 condition => "match1 || match2",
388 }
389
390 filter_caller => "as string"
391
392 filter_caller => qr/as regexp/
393
395 Examples:
396
397 my $log = Log::Handler->new( config => "logger.conf" );
398
399 # or
400
401 $log->add( config => "logger.conf" );
402
403 # or
404
405 $log->config( config => "logger.conf" );
406
407 Example with Config::General.
408
409 Script:
410
411 use Log::Handler;
412
413 my $log = Log::Handler->new();
414
415 $log->config( config => "logger.conf" );
416
417 Config (logger.conf):
418
419 <file>
420 alias = common
421 filename = example.log
422 maxlevel = info
423 minlevel = warn
424 </file>
425
426 <file>
427 alias = error
428 filename = example-error.log
429 maxlevel = warn
430 minlevel = emergency
431 </file>
432
433 <file>
434 alias = debug
435 filename = example-debug.log
436 maxlevel = debug
437 minlevel = debug
438 </file>
439
440 <screen>
441 log_to = STDERR
442 dump = 1
443 maxlevel = debug
444 minlevel = debug
445 </screen>
446
448 It can be very useful if you want to check if a level is active.
449
450 use Log::Handler;
451 use Data::Dumper;
452
453 my $log = Log::Handler->new();
454
455 $log->add(
456 file => {
457 filename => "file1.log",
458 maxlevel => 4,
459 }
460 );
461
462 my %hash = (foo => 1, bar => 2);
463
464 Now you want to dump the hash, but not in any case.
465
466 if ( $log->is_debug ) {
467 my $dump = Dumper(\%hash);
468 $log->debug($dump);
469 }
470
471 This would dump the hash only if the level debug is active.
472
474 Jonny Schulz <jschulz.cpan(at)bloonix.de>.
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478perl v5.36.0 2023-01-20 Log::Handler::Examples(3)