1Apache2::Request(3)   User Contributed Perl Documentation  Apache2::Request(3)
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NAME

6       Apache2::Request - Methods for dealing with client request data
7

SYNOPSIS

9           use Apache2::Request;
10           $req = Apache2::Request->new($r);
11           @foo = $req->param("foo");
12           $bar = $req->args("bar");
13

DESCRIPTION

15       The Apache2::Request module provides methods for parsing GET and POST
16       parameters encoded with either application/x-www-form-urlencoded or
17       multipart/form-data.  Although Apache2::Request provides a few new APIs
18       for accessing the parsed data, it remains largely backwards-compatible
19       with the original 1.X API.  See the "PORTING from 1.X" section below
20       for a list of known issues.
21
22       This manpage documents the Apache2::Request package.
23

Apache2::Request

25       The interface is designed to mimic the CGI.pm routines for parsing
26       query parameters. The main differences are
27
28       •   "Apache2::Request::new" takes an environment-specific
29                   object $r as (second) argument.  Newer versions of CGI.pm
30           also accept
31                   this syntax within modperl.
32
33       •   The query parameters are stored in APR::Table derived objects, and
34                   are therefore retrieved from the table by using case-
35           insensitive keys.
36
37       •   The query string is always parsed immediately, even for POST
38           requests.
39
40   new
41           Apache2::Request->new($r, %args)
42
43       Creates a new Apache2::Request object.
44
45           my $req = Apache2::Request->new($r, POST_MAX => "1M");
46
47       With mod_perl2, the environment object $r must be an
48       Apache2::RequestRec object.  In that case, all methods from
49       Apache2::RequestRec are inherited.  In the (default) CGI environment,
50       $r must be an APR::Pool object.
51
52       The following args are optional:
53
54       •   "POST_MAX", "MAX_BODY"
55
56           Limit the size of POST data (in bytes).
57
58       •   "DISABLE_UPLOADS"
59
60           Disable file uploads.
61
62       •   "TEMP_DIR"
63
64           Sets the directory where upload files are spooled.  On a *nix-like
65           that supports link(2), the TEMP_DIR should be located on the same
66           file system as the final destination file:
67
68            use Apache2::Upload;
69            my $req = Apache2::Request->new($r, TEMP_DIR => "/home/httpd/tmp");
70            my $upload = $req->upload('file');
71            $upload->link("/home/user/myfile");
72
73           For more details on "link", see Apache2::Upload.
74
75       •   "HOOK_DATA"
76
77           Extra configuration info passed as the fourth argument to an upload
78           hook.  See the description for the next item, "UPLOAD_HOOK".
79
80       •   "UPLOAD_HOOK"
81
82           Sets up a callback to run whenever file upload data is read. This
83           can be used to provide an upload progress meter during file
84           uploads.  Apache will automatically continue writing the original
85           data to $upload->fh after the hook exits.
86
87             my $transparent_hook = sub {
88               my ($upload, $data, $data_len, $hook_data) = @_;
89               warn "$hook_data: got $data_len bytes for " . $upload->name;
90             };
91
92             my $req = Apache2::Request->new($r,
93                                             HOOK_DATA => "Note",
94                                             UPLOAD_HOOK => $transparent_hook,
95                                            );
96
97   instance
98           Apache2::Request->instance($r)
99
100       The default (and only) behavior of Apache2::Request is to intelligently
101       cache POST data for the duration of the request.  Thus there is no
102       longer the need for a separate "instance()" method as existed in
103       Apache2::Request for Apache 1.3 - all POST data is always available
104       from each and every Apache2::Request object created during the
105       request's lifetime.
106
107       However an "instance()" method is aliased to "new()" in this release to
108       ease the pain of porting from 1.X to 2.X.
109
110   param
111           $req->param()
112           $req->param($name)
113
114       Get the request parameters (using case-insensitive keys) by mimicing
115       the OO interface of "CGI::param".
116
117           # similar to CGI.pm
118
119           my $foo_value   = $req->param('foo');
120           my @foo_values  = $req->param('foo');
121           my @param_names = $req->param;
122
123           # the following differ slightly from CGI.pm
124
125           # returns ref to APR::Request::Param::Table object representing
126           # all (args + body) params
127           my $table = $req->param;
128           @table_keys = keys %$table;
129
130       In list context, or when invoked with no arguments as "$req->param()",
131       "param" induces libapreq2 to read and parse all remaining data in the
132       request body.  However, "scalar $req->param("foo")" is lazy: libapreq2
133       will only read and parse more data if
134
135           1) no "foo" param appears in the query string arguments, AND
136           2) no "foo" param appears in the previously parsed POST data.
137
138       In this circumstance libapreq2 will read and parse additional blocks of
139       the incoming request body until either
140
141           1) it has found the the "foo" param, or
142           2) parsing is completed.
143
144       Observe that "scalar $req->param("foo")" will not raise an exception if
145       it can locate "foo" in the existing body or args tables, even if the
146       query-string parser or the body parser has failed.  In all other
147       circumstances "param" will throw an Apache2::Request::Error object into
148       $@ should either parser fail.
149
150           $req->args_status(1); # set error state for query-string parser
151           ok $req->param_status == 1;
152
153           $foo = $req->param("foo");
154           ok $foo == 1;
155           eval { @foo = $req->param("foo") };
156           ok $@->isa("Apache2::Request::Error");
157           undef $@;
158           eval { my $not_found = $req->param("non-existent-param") };
159           ok $@->isa("Apache2::Request::Error");
160
161           $req->args_status(0); # reset query-string parser state to "success"
162
163       Note: modifications to the "scalar $req->param()" table only affect the
164       returned table object (the underlying C apr_table_t is generated from
165       the parse data by apreq_params()).  Modifications do not affect the
166       actual request data, and will not be seen by other libapreq2
167       applications.
168
169   parms, params
170       The functionality of these functions is assumed by "param", so they are
171       no longer necessary.  Aliases to "param" are provided in this release
172       for backwards compatibility, however they are deprecated and may be
173       removed from a future release.
174
175   body
176           $req->body()
177           $req->body($name)
178
179       Returns an APR::Request::Param::Table object containing the POST data
180       parameters of the Apache2::Request object.
181
182           my $body = $req->body;
183
184       An optional name parameter can be passed to return the POST data
185       parameter associated with the given name:
186
187           my $foo_body = $req->body("foo");
188
189       More generally, "body()" follows the same pattern as "param()" with
190       respect to its return values and argument list.  The main difference is
191       that modifications to the "scalar $req->body()" table affect the
192       underlying apr_table_t attribute in apreq_request_t, so their impact
193       will be noticed by all libapreq2 applications during this request.
194
195   upload
196           $req->upload()
197           $req->upload($name)
198
199       Requires "Apache2::Upload".  With no arguments, this method returns an
200       APR::Request::Param::Table object in scalar context, or the names of
201       all Apache2::Upload objects in list context.
202
203       An optional name parameter can be passed to return the Apache2::Upload
204       object associated with the given name:
205
206           my $upload = $req->upload($name);
207
208       More generally, "upload()" follows the same pattern as "param()" with
209       respect to its return values and argument list.  The main difference is
210       that its returned values are Apache2::Upload object refs, not simple
211       scalars.
212
213       Note: modifications to the "scalar $req->upload()" table only affect
214       the returned table object (the underlying C apr_table_t is generated by
215       apreq_uploads()).  They do not affect the actual request data, and will
216       not be seen by other libapreq2 applications.
217
218   args_status
219           $req->args_status()
220
221       Get the APR status code of the query-string parser.  APR_SUCCESS on
222       success, error otherwise.
223
224   body_status
225           $req->body_status()
226
227       Get the current APR status code of the parsed POST data.  APR_SUCCESS
228       when parser has completed, APR_INCOMPLETE if parser has more data to
229       parse, APR_EINIT if no post data has been parsed, error otherwise.
230
231   param_status
232           $req->param_status()
233
234       In scalar context, this returns "args_status" if there was an error
235       during the query-string parse, otherwise this returns "body_status", ie
236
237           $req->args_status || $req->body_status
238
239       In list context "param_status" returns the list "(args_status,
240       body_status)".
241
242   parse
243           $req->parse()
244
245       Forces the request to be parsed immediately.  In void context, this
246       will throw an APR::Request::Error should the either the query-string or
247       body parser fail. In all other contexts it will return the two parsers'
248       combined APR status code
249
250           $req->body_status || $req->args_status
251
252       However "parse" should be avoided in most normal situations.  For
253       example, in a mod_perl content handler it is more efficient to write
254
255           sub handler {
256               my $r = shift;
257               my $req = Apache2::Request->new($r);
258               $r->discard_request_body;   # efficiently parses the request body
259               my $parser_status = $req->body_status;
260
261               #...
262           }
263
264       Calling "$r->discard_request_body" outside the content handler is
265       generally a mistake, so use "$req->parse" there, but only as a last
266       resort.  The Apache2::Request API is designed around a lazy-parsing
267       scheme, so calling "parse" should not affect the behavior of any other
268       methods.
269

SUBCLASSING Apache2::Request

271       If the instances of your subclass are hash references then you can
272       actually inherit from Apache2::Request as long as the Apache2::Request
273       object is stored in an attribute called "r" or "_r". (The
274       Apache2::Request class effectively does the delegation for you
275       automagically, as long as it knows where to find the Apache2::Request
276       object to delegate to.)  For example:
277
278               package MySubClass;
279               use Apache2::Request;
280               our @ISA = qw(Apache2::Request);
281               sub new {
282                       my($class, @args) = @_;
283                       return bless { r => Apache2::Request->new(@args) }, $class;
284               }
285

PORTING from 1.X

287       This is the complete list of changes to existing methods from
288       Apache2::Request 1.X.  These issues need to be addressed when porting
289       1.X apps to the new 2.X API.
290
291       •   Apache2::Upload is now a separate module.  Applications
292                   requiring the upload API must "use Apache2::Upload" in 2.X.
293                   This is easily addressed by preloading the modules during
294                   server startup.
295
296       •   You can no longer add (or set or delete) parameters in the
297                   "scalar $req->param", "scalar $req->args" or
298                   "scalar $req->body" tables.  Nor can you add (or set or
299           delete)
300                   cookies in the "scalar $req->jar" table.
301
302       •   "instance()" is now identical to "new()", and is now deprecated.
303           It
304                   may be removed from a future 2.X release.
305
306       •   "param" includes the functionality of "parms()" and "params()", so
307                   they are now deprecated and may be removed from a future
308           2.X release.
309
310       •   "param" called in a list context no longer returns a unique list of
311                   paramaters.  The returned list contains multiple instances
312           of the
313                   parameter name for multivalued fields.
314

SEE ALSO

316       APR::Request::Param, APR::Request::Error, Apache2::Upload,
317       Apache2::Cookie, APR::Table(3).
318
320         Licensed to the Apache Software Foundation (ASF) under one or more
321         contributor license agreements.  See the NOTICE file distributed with
322         this work for additional information regarding copyright ownership.
323         The ASF licenses this file to You under the Apache License, Version 2.0
324         (the "License"); you may not use this file except in compliance with
325         the License.  You may obtain a copy of the License at
326
327             http://www.apache.org/licenses/LICENSE-2.0
328
329         Unless required by applicable law or agreed to in writing, software
330         distributed under the License is distributed on an "AS IS" BASIS,
331         WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
332         See the License for the specific language governing permissions and
333         limitations under the License.
334
335
336
337perl v5.34.0                      2021-07-22               Apache2::Request(3)
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