HTTP::Request::Common
HTTP::Request::Common(User Contributed Perl DocumentatHTTP::Request::Common(3)
NAME
HTTP::Request::Common - Construct common HTTP::Request objects
SYNOPSIS
use HTTP::Request::Common;
$ua = LWP::UserAgent->new;
$ua->request(GET 'http://www.sn.no/');
$ua->request(POST 'http://somewhere/foo', [foo => bar, bar => foo]);
DESCRIPTION
This module provide functions that return newly created "HTTP::Request"
objects. These functions are usually more convenient to use than the
standard "HTTP::Request" constructor for the most common requests. The
following functions are provided:
GET $url
GET $url, Header => Value,...
The GET() function returns an "HTTP::Request" object initialized
with the "GET" method and the specified URL. It is roughly equiva-
lent to the following call
HTTP::Request->new(
GET => $url,
HTTP::Headers->new(Header => Value,...),
)
but is less cluttered. What is different is that a header named
"Content" will initialize the content part of the request instead
of setting a header field. Note that GET requests should normally
not have a content, so this hack makes more sense for the PUT() and
POST() functions described below.
The get(...) method of "LWP::UserAgent" exists as a shortcut for
$ua->request(GET ...).
HEAD $url
HEAD $url, Header => Value,...
Like GET() but the method in the request is "HEAD".
The head(...) method of "LWP::UserAgent" exists as a shortcut for
$ua->request(HEAD ...).
PUT $url
PUT $url, Header => Value,...
PUT $url, Header => Value,..., Content => $content
Like GET() but the method in the request is "PUT".
The content of the request can be specified using the "Content"
pseudo-header. This steals a bit of the header field namespace as
there is no way to directly specify a header that is actually
called "Content". If you really need this you must update the
request returned in a separate statement.
POST $url
POST $url, Header => Value,...
POST $url, $form_ref, Header => Value,...
POST $url, Header => Value,..., Content => $form_ref
POST $url, Header => Value,..., Content => $content
This works mostly like PUT() with "POST" as the method, but this
function also takes a second optional array or hash reference
parameter $form_ref. As for PUT() the content can also be speci-
fied directly using the "Content" pseudo-header, and you may also
provide the $form_ref this way.
The $form_ref argument can be used to pass key/value pairs for the
form content. By default we will initialize a request using the
"application/x-www-form-urlencoded" content type. This means that
you can emulate a HTML <form> POSTing like this:
POST 'http://www.perl.org/survey.cgi',
[ name => 'Gisle Aas',
email => 'gisle@aas.no',
gender => 'M',
born => '1964',
perc => '3%',
];
This will create a HTTP::Request object that looks like this:
POST http://www.perl.org/survey.cgi
Content-Length: 66
Content-Type: application/x-www-form-urlencoded
name=Gisle%20Aas&email=gisle%40aas.no&gender=M&born=1964&perc=3%25
Multivalued form fields can be specified by either repeating the
field name or by passing the value as an array reference.
The POST method also supports the "multipart/form-data" content
used for Form-based File Upload as specified in RFC 1867. You
trigger this content format by specifying a content type of
'form-data' as one of the request headers. If one of the values in
the $form_ref is an array reference, then it is treated as a file
part specification with the following interpretation:
[ $file, $filename, Header => Value... ]
[ undef, $filename, Header => Value,..., Content => $content ]
The first value in the array ($file) is the name of a file to open.
This file will be read and its content placed in the request. The
routine will croak if the file can't be opened. Use an "undef" as
$file value if you want to specify the content directly with a
"Content" header. The $filename is the filename to report in the
request. If this value is undefined, then the basename of the
$file will be used. You can specify an empty string as $filename
if you want to suppress sending the filename when you provide a
$file value.
If a $file is provided by no "Content-Type" header, then "Con-
tent-Type" and "Content-Encoding" will be filled in automatically
with the values returned by LWP::MediaTypes::guess_media_type()
Sending my ~/.profile to the survey used as example above can be
achieved by this:
POST 'http://www.perl.org/survey.cgi',
Content_Type => 'form-data',
Content => [ name => 'Gisle Aas',
email => 'gisle@aas.no',
gender => 'M',
born => '1964',
init => ["$ENV{HOME}/.profile"],
]
This will create a HTTP::Request object that almost looks this (the
boundary and the content of your ~/.profile is likely to be differ-
ent):
POST http://www.perl.org/survey.cgi
Content-Length: 388
Content-Type: multipart/form-data; boundary="6G+f"
--6G+f
Content-Disposition: form-data; name="name"
Gisle Aas
--6G+f
Content-Disposition: form-data; name="email"
gisle@aas.no
--6G+f
Content-Disposition: form-data; name="gender"
M
--6G+f
Content-Disposition: form-data; name="born"
1964
--6G+f
Content-Disposition: form-data; name="init"; filename=".profile"
Content-Type: text/plain
PATH=/local/perl/bin:$PATH
export PATH
--6G+f--
If you set the $DYNAMIC_FILE_UPLOAD variable (exportable) to some
TRUE value, then you get back a request object with a subroutine
closure as the content attribute. This subroutine will read the
content of any files on demand and return it in suitable chunks.
This allow you to upload arbitrary big files without using lots of
memory. You can even upload infinite files like /dev/audio if you
wish; however, if the file is not a plain file, there will be no
Content-Length header defined for the request. Not all servers (or
server applications) like this. Also, if the file(s) change in
size between the time the Content-Length is calculated and the time
that the last chunk is delivered, the subroutine will "Croak".
The post(...) method of "LWP::UserAgent" exists as a shortcut for
$ua->request(POST ...).
SEE ALSO
HTTP::Request, LWP::UserAgent
COPYRIGHT
Copyright 1997-2004, Gisle Aas
This library is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
perl v5.8.6 2007-07-19 HTTP::Request::Common(3)
