File: RequestUtil.pod

package info (click to toggle)
libapache2-mod-perl2 2.0.13-2
  • links: PTS, VCS
  • area: main
  • in suites: sid, trixie
  • size: 12,016 kB
  • sloc: perl: 97,771; ansic: 14,493; makefile: 51; sh: 18
file content (1233 lines) | stat: -rw-r--r-- 27,952 bytes parent folder | download | duplicates (4)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
=head1 NAME

Apache2::RequestUtil - Perl API for Apache request record utils




=head1 Synopsis

  use Apache2::RequestUtil ();
  
  # add httpd config dynamically
  $r->add_config(['require valid-user']);
  
  # dump the request object as a string
  print $r->as_string();
  
  # default content_type
  $content_type = $r->default_type();
  
  # get PerlSetVar/PerlAddVar values
  @values = $r->dir_config->get($key);
  
  # get server docroot
  $docroot = $r->document_root();
  
  # set server docroot
  $r->document_root($new_root);
  
  # what are the registered perl handlers for a given phase
  my @handlers = @{ $r->get_handlers('PerlResponseHandler') || [] };
  
  # push a new handler for a given phase
  $r->push_handlers(PerlCleanupHandler => \&handler);
  
  # set handlers for a given phase (resetting previous values)
  $r->set_handlers(PerlCleanupHandler => []);
  
  # what's the request body limit
  $limit = $r->get_limit_req_body();
  
  # server and port names
  $server = $r->get_server_name();
  $port   = $r->get_server_port();
  
  # what string Apache is going to send for a given status code
  $status_line = Apache2::RequestUtil::get_status_line(404);
  
  # are we in the main request?
  $is_initial = $r->is_initial_req();
  
  # directory level PerlOptions flags lookup
  $r->subprocess_env unless $r->is_perl_option_enabled('SetupEnv');
  
  # current <Location> value
  $location = $r->location();
  
  # merge a <Location> container in a request object
  $r->location_merge($location);
  
  # create a new Apache2::RequestRec object
  $r = Apache2::RequestRec->new($c);
  
  # tell the client not to cache the response
  $r->no_cache($boolean);
  
  # share perl objects by reference like $r->notes
  $r->pnotes($key => [$obj1, $obj2]);
  
  # get HTML signature
  $sig = $r->psignature($prefix);
  
  # get the global request object (requires PerlOptions +GlobalRequest)
  $r = Apache2::RequestUtil->request;
  
  # insert auth credentials into the request as if the client did that
  $r->set_basic_credentials($username, $password);
  
  # slurp the contents of $r->filename
  my $content = ${ $r->slurp_filename() };
  
  # terminate the current child after this request
  $r->child_terminate();







=head1 Description

C<Apache2::RequestUtil> provides the L<Apache request
object|docs::2.0::api::Apache2::RequestRec> utilities API.





=head1 API




=head2 C<add_config>

Dynamically add Apache configuration at request processing runtime:

  $r->add_config($lines);
  $r->add_config($lines, $override);
  $r->add_config($lines, $override, $path);
  $r->add_config($lines, $override, $path, $override_opts);

Configuration directives are processed as if given in a C<E<lt>LocationE<gt>>
block.

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item arg1: C<$lines> (ARRAY ref)

An ARRAY reference containing configuration lines per element, without
the new line terminators.

=item opt arg2: C<$override> ( C<L<Apache2::Const override
constant|docs::2.0::api::Apache2::Const>> )

Which allow-override bits are set

Default value is:
C<L<Apache2::Const::OR_AUTHCFG|docs::2.0::api::Apache2::Const/C_Apache2__Const__OR_AUTHCFG_>>

=item opt arg3: C<$path> ( string )

Set the C<L<Apache2::CmdParms object|docs::2.0::api::Apache2::CmdParms>> C<path> component.
This is the path of the C<E<lt>LocationE<gt>> block. Some directives need this,
for example C<ProxyPassReverse>.

If an empty string is passed a C<NULL> pointer is passed further at C-level.
This is necessary to make something like this work:

  $r->add_config( [
	 	   '<Directory />',
		   'AllowOverride Options AuthConfig',
		   '</Directory>',
                  ], ~0, '' );

Note: C<AllowOverride> is valid only in directory context.

B<Caution:> Some directives need a non-empty path otherwise they cause
segfaults. Thus, use the empty path with caution.

Default value is: C</>

=item opt arg4: C<$override_opts> ( C<L<Apache2::Const options
constant|docs::2.0::api::Apache2::Const>> )

Apache limits the applicable directives in certain situations with
C<AllowOverride>. With Apache 2.2 comes the possibility to enable or
disable single options, for example

  AllowOverride AuthConfig Options=ExecCGI,Indexes

Internally, this directive is parsed into 2 bit fields that are represented
by the C<$override> and C<$override_opts> parameters to C<add_config>.
The above example is parsed into an C<$override> with 2 bits set, one for
C<AuthConfig> the other for C<Options> and an C<$override_opts> with
2 bits set for ExecCGI and Indexes.

When applying other directives, for example C<AuthType> or C<Options> the
appropriate bits in C<$override> must be set. For the C<Options> directive
additionally C<$override_opts> bits must be set.

The C<$override> and C<$override_opts> parameters to C<add_config> are
valid while applying C<$lines>.

C<$override_opts> is new in Apache 2.2. The mod_perl implementation for
Apache 2.0 lets you pass the parameter but ignores it.

Default for C<$override_opts> is:
C<L<Apache2::Const::OPT_UNSET|docs::2.0::api::Apache2::Const/C_Apache2__Const__OPT_UNSET_>> |
C<L<Apache2::Const::OPT_ALL|docs::2.0::api::Apache2::Const/C_Apache2__Const__OPT_ALL_>> |
C<L<Apache2::Const::OPT_INCNOEXEC|docs::2.0::api::Apache2::Const/C_Apache2__Const__OPT_INCNOEXEC_>> |
C<L<Apache2::Const::OPT_SYM_OWNER|docs::2.0::api::Apache2::Const/C_Apache2__Const__OPT_SYM_OWNER_>> |
C<L<Apache2::Const::OPT_MULTI|docs::2.0::api::Apache2::Const/C_Apache2__Const__OPT_MULTI_>>

That means, all options are allowed.

=item ret: no return value

=item since: 2.0.00, C<$path> and C<$override_opts> since 2.0.3

=back

See also:
C<L<$s-E<gt>add_config|docs::2.0::api::Apache2::ServerUtil/C_add_config_>>

For example:

  use Apache2::RequestUtil ();
  use Apache2::Access ();

  $r->add_config(['require valid-user']);

  # this regards the current AllowOverride setting
  $r->add_config(['AuthName secret',
                  'AuthType Basic',
                  'Options ExecCGI'],
                 $r->allow_override, $path, $r->allow_override_opts);





=head2 C<as_string>

Dump the request object as a string

  $dump = $r->as_string();

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item ret: C<$dump> ( string )

=item since: 2.0.00

=back

Dumps various request and response headers (mainly useful for
debugging)




=head2 C<child_terminate>

Terminate the current worker process as soon as the current request is
over

  $r->child_terminate();

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item ret: no return value

=item since: 2.0.00

=back

This method is not supported in threaded MPMs



=head2 C<default_type>

Retrieve the value of the DefaultType directive for the current
request. If not set C<text/plain> is returned.

  $content_type = $r->default_type();

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

The current request

=item ret: C<$content_type> ( string )

The default type

=item since: 2.0.00

=item removed from the C<httpd> API in version 2.3.2

=back






=head2 C<dir_config>

C<$r-E<gt>dir_config()> provides an interface for the per-directory
variable specified by the C<PerlSetVar> and C<PerlAddVar> directives,
and also can be manipulated via the
C<L<APR::Table|docs::2.0::api::APR::Table>> methods.

  $table  = $r->dir_config();
  $value  = $r->dir_config($key);
  @values = $r->dir_config->get($key);
  $r->dir_config($key, $val);

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item opt arg2: C<$key> ( string )

Key string

=item opt arg3: C<$val> ( string )

Value string

=item ret: ...

Depends on the passed arguments, see further discussion

=item since: 2.0.00

=back

The keys are case-insensitive.

  $apr_table = $r->dir_config();

dir_config() called in a scalar context without the C<$key> argument
returns a I<HASH> reference blessed into the
C<L<APR::Table|docs::2.0::api::APR::Table>> class. This object can be
manipulated via the C<L<APR::Table|docs::2.0::api::APR::Table>>
methods. For available methods see
the C<L<APR::Table|docs::2.0::api::APR::Table>> manpage.

  $value = $r->dir_config($key);

If the C<$key> argument is passed in the scalar context only a single
value will be returned. Since the table preserves the insertion order,
if there is more than one value for the same key, the oldest value
associated with the desired key is returned. Calling in the scalar
context is also much faster, as it'll stop searching the table as soon
as the first match happens.

  @values = $r->dir_config->get($key);

To receive a list of values you must use C<get()> method from the
C<L<APR::Table|docs::2.0::api::APR::Table>> class.

  $r->dir_config($key => $val);

If the C<$key> and the C<$val> arguments are used, the set() operation
will happen: all existing values associated with the key C<$key> (and
the key itself) will be deleted and C<$value> will be placed instead.

  $r->dir_config($key => undef);

If C<$val> is I<undef> the unset() operation will happen: all existing
values associated with the key C<$key> (and the key itself) will be
deleted.







=head2 C<document_root>

Retrieve the document root for this server

  $docroot = $r->document_root();
  $docroot = $r->document_root($new_root);

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

The current request

=item opt arg1: C<$new_root>

Sets the document root to a new value B<only for the duration of the
current request>.

Note the L<limited functionality under threaded
MPMs|docs::2.0::api::Apache2::ServerRec/Limited_Functionality_under_Threaded_MPMs>.

=item ret: C<$docroot> ( string )

The document root

=item since: 2.0.00

=back








=head2 C<get_handlers>

Returns a reference to a list of handlers enabled for a given phase.

  $handlers_list = $r->get_handlers($hook_name);

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item arg1: C<$hook_name> ( string )

a string representing the phase to handle (e.g. C<PerlLogHandler>)

=item ret: C<$handlers_list> (ref to an ARRAY of CODE refs)

a list of handler subroutines CODE references

=item since: 2.0.00

=back

See also:
C<L<$s-E<gt>add_config|docs::2.0::api::Apache2::ServerUtil/C_get_handlers_>>

For example:

A list of handlers configured to run at the response phase:

  my @handlers = @{ $r->get_handlers('PerlResponseHandler') || [] };







=head2 C<get_limit_req_body>

Return the limit on bytes in request msg body

  $limit = $r->get_limit_req_body();

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

The current request

=item ret: C<$limit> (integer)

the maximum number of bytes in the request msg body

=item since: 2.0.00

=back





=head2 C<get_server_name>

Get the current request's server name

  $server = $r->get_server_name();

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

The current request

=item ret: C<$server> ( string )

the server name

=item since: 2.0.00

=back

For example, consruct a hostport string:

  use Apache2::RequestUtil ();
  my $hostport = join ':', $r->get_server_name, $r->get_server_port;





=head2 C<get_server_port>

Get the current server port

  $port = $r->get_server_port();

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

The current request

=item ret: C<$port> ( integer )

The server's port number

=item since: 2.0.00

=back

For example, consruct a hostport string:

  use Apache2::RequestUtil ();
  my $hostport = join ':', $r->get_server_name, $r->get_server_port;







=head2 C<get_status_line>

Return the C<Status-Line> for a given status code (excluding the
HTTP-Version field).

  $status_line = Apache2::RequestUtil::get_status_line($status);

=over 4

=item arg1: C<$status> (integer)

The HTTP status code

=item ret: C<$status_line> ( string )

The Status-Line

If an invalid or unknown status code is passed, C<"500 Internal Server
Error"> will be returned.

=item since: 2.0.00

=back

For example:

  use Apache2::RequestUtil ();
  print Apache2::RequestUtil::get_status_line(400);

will print:

  400 Bad Request





=head2 C<is_initial_req>

Determine whether the current request is the main request or a
sub-request

  $is_initial = $r->is_initial_req();

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

A request or a sub-request object

=item ret: C<$is_initial> ( boolean )

If true -- it's the main request, otherwise it's a sub-request

=item since: 2.0.00

=back







=head2 C<is_perl_option_enabled>

check whether a directory level C<PerlOptions> flag is enabled or not.

  $result = $r->is_perl_option_enabled($flag);

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item arg1: C<$flag> ( string )

=item ret: C<$result> ( boolean )

=item since: 2.0.00

=back

For example to check whether the C<SetupEnv> option is enabled for the
current request (which can be disabled with C<PerlOptions -SetupEnv>)
and populate the environment variables table if disabled:

  $r->subprocess_env unless $r->is_perl_option_enabled('SetupEnv');

See also:
L<PerlOptions|docs::2.0::user::config::config/C_PerlOptions_> and
L<the equivalent function for server level PerlOptions
flags|docs::2.0::api::Apache2::ServerUtil/C_is_perl_option_enabled_>.





=head2 C<location>

Get the path of the E<lt>LocationE<gt> section from which the current
C<Perl*Handler> is being called.

  $location = $r->location();

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item ret: C<$location> ( string )

=item since: 2.0.00

=back






=head2 C<location_merge>

Merge a given C<E<lt>LocationE<gt>> container into the current request
object:

  $ret = $r->location_merge($location);

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item arg1: C<$location> ( string )

The argument in a C<E<lt>LocationE<gt>> section. For example to merge
a container:

  <Location /foo>
      ...
  </Location>

that argument will be I</foo>

=item ret: C<$ret> ( boolean )

a true value if the merge was successful (i.e. the request
C<$location> match was found), otherwise false.

=item since: 2.0.00

=back

Useful for insertion of a configuration section into a custom
C<Apache2::RequestRec> object, created via the
C<Apache2::RequestRec-E<gt>new()> method. See for example the L<Command
Server protocol
example|docs::2.0::user::handlers::protocols/Command_Server>.





=head2 C<new>

Create a new C<Apache2::RequestRec> object.

  $r = Apache2::RequestRec->new($c);
  $r = Apache2::RequestRec->new($c, $pool);

=over 4

=item obj: C<Apache2::RequestRec>
( C<L<Apache2::RequestRec class name|docs::2.0::api::Apache2::RequestRec>> )

=item arg1: C<$c>
(C<L<Apache2::Connection object|docs::2.0::api::Apache2::Connection>>)

=item opt arg2: C<$pool>

If no C<$pool> argument is passed, C<$c-E<gt>pool> is used. That means
that the created C<Apache2::RequestRec> object will be valid as long as
the connection object is valid.

=item ret: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item since: 2.0.00

=back

It's possible to reuse the HTTP framework features outside the
familiar HTTP request cycle. It's possible to write your own full or
partial HTTP implementation without needing a running Apache
server. You will need the C<Apache2::RequestRec> object in order to be
able to reuse the rich functionality supplied via this object.

See for example the L<Command Server protocol
example|docs::2.0::user::handlers::protocols/Command_Server> which
reuses HTTP AAA model under non-HTTP protocol.







=head2 C<no_cache>

Add/remove cache control headers:

  $prev_no_cache = $r->no_cache($boolean);

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item arg1: C<$boolean> ( boolean )

A true value sets the C<no_cache> request record member to a true
value and inserts:

  Pragma: no-cache
  Cache-control: no-cache

into the response headers, indicating that the data being returned is
volatile and the client should not cache it.

A false value unsets the C<no_cache> request record member and the
mentioned headers if they were previously set.

=item ret: C<$prev_no_cache> ( boolean )

Should you care, the C<no_cache> request record member value prior to
the change is returned.

=item since: 2.0.00

=back

This method should be invoked before any response data has been sent
out.





=head2 C<pnotes>

Share Perl variables between Perl HTTP handlers

  # to share variables by value and not reference, $val should be a lexical.
  $old_val  = $r->pnotes($key => $val);
  $val      = $r->pnotes($key);
  $hash_ref = $r->pnotes();

B<Note:> sharing variables really means it. The variable is not copied.
Only its reference count is incremented. If it is changed after being
put in pnotes that change also affects the stored value. The following
example illustrates the effect:

  my $v=1;                     my $v=1;
  $r->pnotes( 'v'=>$v );       $r->pnotes->{v}=$v;
  $v++;                        $v++;
  my $x=$r->pnotes('v');       my $x=$r->pnotes->{v};

In both cases C<$x> is C<2> not C<1>. See also C<Apache2::SafePnotes> on
CPAN.

There has been a lot of discussion advocating for pnotes sharing variables
by value and not reference.  Sharing by reference can create 'spooky action
at a distance' effects when the sharing is assumed to share a copy of the
value.  Tim Bunce offers the following summary and suggestion for sharing
by value.

What's wrong with this code:

  sub foo {
      my ($r, $status, $why) = @_;
      $r->pnotes('foo', ($why) ? "$status:$why" : $status);
      return;
  }

Nothing, except it doesn't work as expected due to this pnotes bug: If the 
same code is called in a sub-request then the pnote of $r-E<gt>prev is magically 
updated at a distance to the same value!

Try to explain why that is to anyone not deeply familiar with perl internals!

The fix is to avoid pnotes taking a ref to the invisible op_targ embededed in 
the code by passing a simple lexical variable as the actual argument. That can be done in-line like this:

  sub mark_as_internally_redirected {
      my ($r, $status, $why) = @_;
      $r->pnotes('foo', my $tmp = (($why) ? "$status:$why" : $status));
      return;
  }

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item opt arg1: C<$key> ( string )

A key value

=item opt arg2: C<$val> ( SCALAR )

Any scalar value (e.g. a reference to an array)

=item ret: (3 different possible values)

if both, C<$key> and C<$val> are passed the previous value for C<$key>
is returned if such existed, otherwise C<undef> is returned.

if only C<$key> is passed, the current value for the given key is
returned.

if no arguments are passed, a hash reference is returned, which can
then be directly accessed without going through the C<pnotes()>
interface.

=item since: 2.0.00

=back

This method provides functionality similar to
(C<L<Apache2::RequestRec::notes|docs::2.0::api::Apache2::RequestRec/C_notes_>>),
but values can be any Perl variables. That also means that it can be
used only between Perl modules.

The values get reset automatically at the end of each HTTP request.

Examples:

Set a key/value pair:

  $r->pnotes(foo => [1..5]);

Get the value:

  $val = $r->pnotes("foo");

C<$val> now contains an array ref containing 5 elements (C<1..5>).

Now change the existing value:

  $old_val = $r->pnotes(foo => ['a'..'c']);
  $val = $r->pnotes("foo");

C<$old_val> now contains an array ref with 5 elements (C<1..5>) and
C<$val> contains an array ref with 3 elements C<'a'>, C<'b'>, C<'c'>.

Alternatively you can access the hash reference with all pnotes
values:

  $pnotes = $r->pnotes;

Now we can read what's in there for the key I<foo>:

  $val = $pnotes->{foo};

and as before C<$val> still gives us an array ref with 3 elements
C<'a'>, C<'b'>, C<'c'>.

Now we can add elements to it:

  push @{ $pnotes{foo} }, 'd'..'f';

and we can try to retrieve them using the hash and non-hash API:

  $val1 = $pnotes{foo};
  $val2 = $r->pnotes("foo");

Both C<$val1> and C<$val2> contain an array ref with 6 elements
(letters 'a' to 'f').

Finally to reset an entry you could just assign C<undef> as a value:

  $r->pnotes(foo => undef);

but the entry for the key I<foo> still remains with the value
C<undef>. If you really want to completely remove it, use the hash
interface:

  delete $r->pnotes->{foo};








=head2 C<psignature>

Get HTML describing the address and (optionally) admin of the server.

  $sig = $r->psignature($prefix);

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec|docs::2.0::api::Apache2::RequestRec>> )

=item arg1: C<$prefix> ( string )

Text which is prepended to the return value

=item ret: C<$sig> ( string )

HTML text describing the server. Note that depending on the value of
the C<ServerSignature> directive, the function may return the address,
including the admin information or nothing at all.

=item since: 2.0.00

=back







=head2 C<request>

Get/set the ( C<L<Apache2::RequestRec
object|docs::2.0::api::Apache2::RequestRec>> ) object for the current
request.

  $r = Apache2::RequestUtil->request;
       Apache2::RequestUtil->request($new_r);

=over 4

=item obj: C<Apache2> (class name)

The Apache class name

=item opt arg1: C<$new_r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item ret: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item since: 2.0.00

=back

The get-able part of this method is only available if C<L<PerlOptions
+GlobalRequest|docs::2.0::user::config::config/C_GlobalRequest_>> is
in effect or if C<Apache2-E<gt>request($new_r)> was called earlier. So
instead of setting C<L<PerlOptions
+GlobalRequest|docs::2.0::user::config::config/C_GlobalRequest_>>, one
can set the global request from within the handler.






=head2 C<push_handlers>

Add one or more handlers to a list of handlers to be called for a
given phase.

  $ok = $r->push_handlers($hook_name => \&handler);
  $ok = $r->push_handlers($hook_name => ['Foo::Bar::handler', \&handler2]);

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item arg1: C<$hook_name> ( string )

the phase to add the handlers to

=item arg2: C<$handlers> ( CODE ref or SUB name or an ARRAY ref )

a single handler CODE reference or just a name of the subroutine
(fully qualified unless defined in the current package).

if more than one passed, use a reference to an array of CODE refs
and/or subroutine names.

=item ret: C<$ok> ( boolean )

returns a true value on success, otherwise a false value

=item since: 2.0.00

See also:
C<L<$s-E<gt>add_config|docs::2.0::api::Apache2::ServerUtil/C_push_handlers_>>

Note that to push input/output filters you have to use
C<L<Apache2::Filter|docs::2.0::api::Apache2::Filter>> methods:
C<L<add_input_filter|docs::2.0::api::Apache2::Filter/C_add_input_filter_>>
and
C<L<add_output_filter|docs::2.0::api::Apache2::Filter/C_add_output_filter_>>.

=back

Examples:

A single handler:

  $r->push_handlers(PerlResponseHandler => \&handler);

Multiple handlers:

  $r->push_handlers(PerlFixupHandler => ['Foo::Bar::handler', \&handler2]);

Anonymous functions:

  $r->push_handlers(PerlLogHandler => sub { return Apache2::Const::OK });






=head2 C<set_basic_credentials>

Populate the incoming request headers table (C<headers_in>) with
authentication headers for Basic Authorization as if the client has
submitted those in first place:

  $r->set_basic_credentials($username, $password);

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item arg1: C<$username> ( string )

=item arg2: C<$password> ( string )

=item ret: no return value

=item since: 2.0.00

=back

See for example the L<Command Server protocol
example|docs::2.0::user::handlers::protocols/Command_Server> which
reuses HTTP AAA model under non-HTTP protocol.







=head2 C<set_handlers>

Set a list of handlers to be called for a given phase. Any previously
set handlers are forgotten.

  $ok = $r->set_handlers($hook_name => \&handler);
  $ok = $r->set_handlers($hook_name => ['Foo::Bar::handler', \&handler2]);
  $ok = $r->set_handlers($hook_name => []);
  $ok = $r->set_handlers($hook_name => undef);

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item arg1: C<$hook_name> ( string )

the phase to set the handlers in

=item arg2: C<$handlers> (CODE ref or SUB name or an ARRAY ref)

a reference to a single handler CODE reference or just a name of the
subroutine (fully qualified unless defined in the current package).

if more than one passed, use a reference to an array of CODE refs
and/or subroutine names.

if the argument is C<undef> or C<[]> the list of handlers is reset to
zero.

=item ret: C<$ok> ( boolean )

returns a true value on success, otherwise a false value

=item since: 2.0.00

=back

See also:
C<L<$s-E<gt>add_config|docs::2.0::api::Apache2::ServerUtil/C_set_handlers_>>

Examples:

A single handler:

  $r->set_handlers(PerlResponseHandler => \&handler);

Multiple handlers:

  $r->set_handlers(PerlFixupHandler => ['Foo::Bar::handler', \&handler2]);

Anonymous functions:

  $r->set_handlers(PerlLogHandler => sub { return Apache2::Const::OK });

Reset any previously set handlers:

  $r->set_handlers(PerlCleanupHandler => []);

or

  $r->set_handlers(PerlCleanupHandler => undef);







=head2 C<slurp_filename>

Slurp the contents of C<$r-E<gt>filename>:

  $content_ref = $r->slurp_filename($tainted);

=over 4

=item obj: C<$r>
( C<L<Apache2::RequestRec object|docs::2.0::api::Apache2::RequestRec>> )

=item arg1: C<$tainted> (number)

If the server is run under the tainting mode (C<-T>) which we hope you
do, by default the returned data is tainted. If an optional
C<$tainted> flag is set to zero, the data will be marked as
non-tainted.

Do B<not> set this flag to zero unless you know what you are doing,
you may create a security hole in your program if you do. For more
information see the I<perlsec> manpage.

If you wonder why this option is available, it is used internally by
the C<L<ModPerl::Registry|docs::2.0::api::ModPerl::Registry>> handler
and friends, because the CGI scripts that it reads are considered safe
(you could just as well C<require()> them).

=item ret: C<$content_ref> ( SCALAR ref )

A reference to a string with the contents

=item excpt: C<L<APR::Error|docs::2.0::api::APR::Error>>

Possible error codes could be:
C<L<APR::Const::EACCES|docs::2.0::api::APR::Const/C_APR__Const__EACCES_>>
(permission problems),
C<L<APR::Const::ENOENT|docs::2.0::api::APR::Const/C_APR__Const__ENOENT_>>
(file not found), and others. For checking such error codes, see the
documentation for, for example,
C<L<APR::Status::is_EACCES|docs::2.0::api::APR::Status/C_is_EACCES_>>
and
C<L<APR::Status::is_ENOENT|docs::2.0::api::APR::Status/C_is_ENOENT_>>.


=item since: 2.0.00

=back

Note that if you assign to C<$r-E<gt>filename> you need to L<update
its stat record|docs::2.0::api::Apache2::RequestRec/C_filename_>.





=head1 See Also

L<mod_perl 2.0 documentation|docs::2.0::index>.




=head1 Copyright

mod_perl 2.0 and its core modules are copyrighted under
The Apache Software License, Version 2.0.




=head1 Authors

L<The mod_perl development team and numerous
contributors|about::contributors::people>.

=cut