[27174] | 1 | package LWP;
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| 2 |
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[27183] | 3 | $VERSION = "5.837";
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[27174] | 4 | sub Version { $VERSION; }
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| 5 |
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[27183] | 6 | require 5.005;
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[27174] | 7 | require LWP::UserAgent; # this should load everything you need
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| 8 |
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| 9 | 1;
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| 10 |
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| 11 | __END__
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| 12 |
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| 13 | =head1 NAME
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| 14 |
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| 15 | LWP - The World-Wide Web library for Perl
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| 16 |
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| 17 | =head1 SYNOPSIS
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| 18 |
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| 19 | use LWP;
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| 20 | print "This is libwww-perl-$LWP::VERSION\n";
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| 21 |
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| 22 |
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| 23 | =head1 DESCRIPTION
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| 24 |
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| 25 | The libwww-perl collection is a set of Perl modules which provides a
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| 26 | simple and consistent application programming interface (API) to the
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| 27 | World-Wide Web. The main focus of the library is to provide classes
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| 28 | and functions that allow you to write WWW clients. The library also
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| 29 | contain modules that are of more general use and even classes that
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| 30 | help you implement simple HTTP servers.
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| 31 |
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| 32 | Most modules in this library provide an object oriented API. The user
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| 33 | agent, requests sent and responses received from the WWW server are
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| 34 | all represented by objects. This makes a simple and powerful
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| 35 | interface to these services. The interface is easy to extend
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| 36 | and customize for your own needs.
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| 37 |
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| 38 | The main features of the library are:
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| 39 |
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| 40 | =over 3
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| 41 |
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| 42 | =item *
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| 43 |
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| 44 | Contains various reusable components (modules) that can be
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| 45 | used separately or together.
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| 46 |
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| 47 | =item *
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| 48 |
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| 49 | Provides an object oriented model of HTTP-style communication. Within
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| 50 | this framework we currently support access to http, https, gopher, ftp, news,
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| 51 | file, and mailto resources.
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| 52 |
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| 53 | =item *
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| 54 |
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| 55 | Provides a full object oriented interface or
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| 56 | a very simple procedural interface.
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| 57 |
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| 58 | =item *
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| 59 |
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| 60 | Supports the basic and digest authorization schemes.
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| 61 |
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| 62 | =item *
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| 63 |
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| 64 | Supports transparent redirect handling.
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| 65 |
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| 66 | =item *
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| 67 |
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| 68 | Supports access through proxy servers.
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| 69 |
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| 70 | =item *
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| 71 |
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| 72 | Provides parser for F<robots.txt> files and a framework for constructing robots.
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| 73 |
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| 74 | =item *
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| 75 |
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| 76 | Supports parsing of HTML forms.
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| 77 |
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| 78 | =item *
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| 79 |
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| 80 | Implements HTTP content negotiation algorithm that can
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| 81 | be used both in protocol modules and in server scripts (like CGI
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| 82 | scripts).
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| 83 |
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| 84 | =item *
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| 85 |
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| 86 | Supports HTTP cookies.
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| 87 |
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| 88 | =item *
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| 89 |
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| 90 | Some simple command line clients, for instance C<lwp-request> and C<lwp-download>.
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| 91 |
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| 92 | =back
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| 93 |
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| 94 |
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| 95 | =head1 HTTP STYLE COMMUNICATION
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| 96 |
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| 97 |
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| 98 | The libwww-perl library is based on HTTP style communication. This
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| 99 | section tries to describe what that means.
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| 100 |
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| 101 | Let us start with this quote from the HTTP specification document
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[27183] | 102 | <URL:http://www.w3.org/pub/WWW/Protocols/>:
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[27174] | 103 |
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| 104 | =over 3
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| 105 |
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| 106 | =item
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| 107 |
|
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| 108 | The HTTP protocol is based on a request/response paradigm. A client
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| 109 | establishes a connection with a server and sends a request to the
|
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| 110 | server in the form of a request method, URI, and protocol version,
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| 111 | followed by a MIME-like message containing request modifiers, client
|
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| 112 | information, and possible body content. The server responds with a
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| 113 | status line, including the message's protocol version and a success or
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| 114 | error code, followed by a MIME-like message containing server
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| 115 | information, entity meta-information, and possible body content.
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| 116 |
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| 117 | =back
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| 118 |
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| 119 | What this means to libwww-perl is that communication always take place
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| 120 | through these steps: First a I<request> object is created and
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| 121 | configured. This object is then passed to a server and we get a
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| 122 | I<response> object in return that we can examine. A request is always
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| 123 | independent of any previous requests, i.e. the service is stateless.
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| 124 | The same simple model is used for any kind of service we want to
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| 125 | access.
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| 126 |
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| 127 | For example, if we want to fetch a document from a remote file server,
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| 128 | then we send it a request that contains a name for that document and
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| 129 | the response will contain the document itself. If we access a search
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| 130 | engine, then the content of the request will contain the query
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| 131 | parameters and the response will contain the query result. If we want
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| 132 | to send a mail message to somebody then we send a request object which
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| 133 | contains our message to the mail server and the response object will
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| 134 | contain an acknowledgment that tells us that the message has been
|
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| 135 | accepted and will be forwarded to the recipient(s).
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| 136 |
|
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| 137 | It is as simple as that!
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| 138 |
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| 139 |
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| 140 | =head2 The Request Object
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| 141 |
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| 142 | The libwww-perl request object has the class name C<HTTP::Request>.
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| 143 | The fact that the class name uses C<HTTP::> as a
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| 144 | prefix only implies that we use the HTTP model of communication. It
|
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| 145 | does not limit the kind of services we can try to pass this I<request>
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| 146 | to. For instance, we will send C<HTTP::Request>s both to ftp and
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| 147 | gopher servers, as well as to the local file system.
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| 148 |
|
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| 149 | The main attributes of the request objects are:
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| 150 |
|
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| 151 | =over 3
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| 152 |
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| 153 | =item *
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| 154 |
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[27183] | 155 | The B<method> is a short string that tells what kind of
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[27174] | 156 | request this is. The most common methods are B<GET>, B<PUT>,
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| 157 | B<POST> and B<HEAD>.
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| 158 |
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| 159 | =item *
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| 160 |
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[27183] | 161 | The B<uri> is a string denoting the protocol, server and
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[27174] | 162 | the name of the "document" we want to access. The B<uri> might
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| 163 | also encode various other parameters.
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| 164 |
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| 165 | =item *
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| 166 |
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[27183] | 167 | The B<headers> contain additional information about the
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[27174] | 168 | request and can also used to describe the content. The headers
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| 169 | are a set of keyword/value pairs.
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| 170 |
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| 171 | =item *
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| 172 |
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[27183] | 173 | The B<content> is an arbitrary amount of data.
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[27174] | 174 |
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| 175 | =back
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| 176 |
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| 177 | =head2 The Response Object
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| 178 |
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| 179 | The libwww-perl response object has the class name C<HTTP::Response>.
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| 180 | The main attributes of objects of this class are:
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| 181 |
|
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| 182 | =over 3
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| 183 |
|
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| 184 | =item *
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| 185 |
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[27183] | 186 | The B<code> is a numerical value that indicates the overall
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[27174] | 187 | outcome of the request.
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| 188 |
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| 189 | =item *
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| 190 |
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[27183] | 191 | The B<message> is a short, human readable string that
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[27174] | 192 | corresponds to the I<code>.
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| 193 |
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| 194 | =item *
|
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| 195 |
|
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[27183] | 196 | The B<headers> contain additional information about the
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[27174] | 197 | response and describe the content.
|
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| 198 |
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| 199 | =item *
|
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| 200 |
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[27183] | 201 | The B<content> is an arbitrary amount of data.
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[27174] | 202 |
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| 203 | =back
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| 204 |
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| 205 | Since we don't want to handle all possible I<code> values directly in
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| 206 | our programs, a libwww-perl response object has methods that can be
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| 207 | used to query what kind of response this is. The most commonly used
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| 208 | response classification methods are:
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| 209 |
|
---|
| 210 | =over 3
|
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| 211 |
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| 212 | =item is_success()
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| 213 |
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[27183] | 214 | The request was was successfully received, understood or accepted.
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[27174] | 215 |
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| 216 | =item is_error()
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| 217 |
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| 218 | The request failed. The server or the resource might not be
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| 219 | available, access to the resource might be denied or other things might
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| 220 | have failed for some reason.
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| 221 |
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| 222 | =back
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| 223 |
|
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| 224 | =head2 The User Agent
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| 225 |
|
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| 226 | Let us assume that we have created a I<request> object. What do we
|
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| 227 | actually do with it in order to receive a I<response>?
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| 228 |
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| 229 | The answer is that you pass it to a I<user agent> object and this
|
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| 230 | object takes care of all the things that need to be done
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| 231 | (like low-level communication and error handling) and returns
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| 232 | a I<response> object. The user agent represents your
|
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| 233 | application on the network and provides you with an interface that
|
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| 234 | can accept I<requests> and return I<responses>.
|
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| 235 |
|
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| 236 | The user agent is an interface layer between
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| 237 | your application code and the network. Through this interface you are
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| 238 | able to access the various servers on the network.
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| 239 |
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| 240 | The class name for the user agent is C<LWP::UserAgent>. Every
|
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| 241 | libwww-perl application that wants to communicate should create at
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| 242 | least one object of this class. The main method provided by this
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| 243 | object is request(). This method takes an C<HTTP::Request> object as
|
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| 244 | argument and (eventually) returns a C<HTTP::Response> object.
|
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| 245 |
|
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| 246 | The user agent has many other attributes that let you
|
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| 247 | configure how it will interact with the network and with your
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| 248 | application.
|
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| 249 |
|
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| 250 | =over 3
|
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| 251 |
|
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| 252 | =item *
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| 253 |
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[27183] | 254 | The B<timeout> specifies how much time we give remote servers to
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[27174] | 255 | respond before the library disconnects and creates an
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| 256 | internal I<timeout> response.
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| 257 |
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| 258 | =item *
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| 259 |
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[27183] | 260 | The B<agent> specifies the name that your application should use when it
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[27174] | 261 | presents itself on the network.
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| 262 |
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| 263 | =item *
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| 264 |
|
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[27183] | 265 | The B<from> attribute can be set to the e-mail address of the person
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[27174] | 266 | responsible for running the application. If this is set, then the
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| 267 | address will be sent to the servers with every request.
|
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| 268 |
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| 269 | =item *
|
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| 270 |
|
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[27183] | 271 | The B<parse_head> specifies whether we should initialize response
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[27174] | 272 | headers from the E<lt>head> section of HTML documents.
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| 273 |
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---|
| 274 | =item *
|
---|
| 275 |
|
---|
[27183] | 276 | The B<proxy> and B<no_proxy> attributes specify if and when to go through
|
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| 277 | a proxy server. <URL:http://www.w3.org/pub/WWW/Proxies/>
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[27174] | 278 |
|
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| 279 | =item *
|
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| 280 |
|
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[27183] | 281 | The B<credentials> provide a way to set up user names and
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[27174] | 282 | passwords needed to access certain services.
|
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| 283 |
|
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| 284 | =back
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| 285 |
|
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| 286 | Many applications want even more control over how they interact
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| 287 | with the network and they get this by sub-classing
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| 288 | C<LWP::UserAgent>. The library includes a
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| 289 | sub-class, C<LWP::RobotUA>, for robot applications.
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| 290 |
|
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| 291 | =head2 An Example
|
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| 292 |
|
---|
| 293 | This example shows how the user agent, a request and a response are
|
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| 294 | represented in actual perl code:
|
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| 295 |
|
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| 296 | # Create a user agent object
|
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| 297 | use LWP::UserAgent;
|
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| 298 | my $ua = LWP::UserAgent->new;
|
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| 299 | $ua->agent("MyApp/0.1 ");
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| 300 |
|
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| 301 | # Create a request
|
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| 302 | my $req = HTTP::Request->new(POST => 'http://search.cpan.org/search');
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| 303 | $req->content_type('application/x-www-form-urlencoded');
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| 304 | $req->content('query=libwww-perl&mode=dist');
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| 305 |
|
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| 306 | # Pass request to the user agent and get a response back
|
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| 307 | my $res = $ua->request($req);
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| 308 |
|
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| 309 | # Check the outcome of the response
|
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| 310 | if ($res->is_success) {
|
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| 311 | print $res->content;
|
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| 312 | }
|
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| 313 | else {
|
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| 314 | print $res->status_line, "\n";
|
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| 315 | }
|
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| 316 |
|
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| 317 | The $ua is created once when the application starts up. New request
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| 318 | objects should normally created for each request sent.
|
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| 319 |
|
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| 320 |
|
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| 321 | =head1 NETWORK SUPPORT
|
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| 322 |
|
---|
| 323 | This section discusses the various protocol schemes and
|
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| 324 | the HTTP style methods that headers may be used for each.
|
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| 325 |
|
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| 326 | For all requests, a "User-Agent" header is added and initialized from
|
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| 327 | the $ua->agent attribute before the request is handed to the network
|
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| 328 | layer. In the same way, a "From" header is initialized from the
|
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| 329 | $ua->from attribute.
|
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| 330 |
|
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| 331 | For all responses, the library adds a header called "Client-Date".
|
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| 332 | This header holds the time when the response was received by
|
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| 333 | your application. The format and semantics of the header are the
|
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| 334 | same as the server created "Date" header. You may also encounter other
|
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| 335 | "Client-XXX" headers. They are all generated by the library
|
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| 336 | internally and are not received from the servers.
|
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| 337 |
|
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| 338 | =head2 HTTP Requests
|
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| 339 |
|
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| 340 | HTTP requests are just handed off to an HTTP server and it
|
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| 341 | decides what happens. Few servers implement methods beside the usual
|
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| 342 | "GET", "HEAD", "POST" and "PUT", but CGI-scripts may implement
|
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| 343 | any method they like.
|
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| 344 |
|
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| 345 | If the server is not available then the library will generate an
|
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| 346 | internal error response.
|
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| 347 |
|
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| 348 | The library automatically adds a "Host" and a "Content-Length" header
|
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| 349 | to the HTTP request before it is sent over the network.
|
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| 350 |
|
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| 351 | For a GET request you might want to add a "If-Modified-Since" or
|
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| 352 | "If-None-Match" header to make the request conditional.
|
---|
| 353 |
|
---|
| 354 | For a POST request you should add the "Content-Type" header. When you
|
---|
| 355 | try to emulate HTML E<lt>FORM> handling you should usually let the value
|
---|
| 356 | of the "Content-Type" header be "application/x-www-form-urlencoded".
|
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| 357 | See L<lwpcook> for examples of this.
|
---|
| 358 |
|
---|
| 359 | The libwww-perl HTTP implementation currently support the HTTP/1.1
|
---|
| 360 | and HTTP/1.0 protocol.
|
---|
| 361 |
|
---|
| 362 | The library allows you to access proxy server through HTTP. This
|
---|
| 363 | means that you can set up the library to forward all types of request
|
---|
| 364 | through the HTTP protocol module. See L<LWP::UserAgent> for
|
---|
| 365 | documentation of this.
|
---|
| 366 |
|
---|
| 367 |
|
---|
| 368 | =head2 HTTPS Requests
|
---|
| 369 |
|
---|
| 370 | HTTPS requests are HTTP requests over an encrypted network connection
|
---|
| 371 | using the SSL protocol developed by Netscape. Everything about HTTP
|
---|
| 372 | requests above also apply to HTTPS requests. In addition the library
|
---|
| 373 | will add the headers "Client-SSL-Cipher", "Client-SSL-Cert-Subject" and
|
---|
| 374 | "Client-SSL-Cert-Issuer" to the response. These headers denote the
|
---|
| 375 | encryption method used and the name of the server owner.
|
---|
| 376 |
|
---|
| 377 | The request can contain the header "If-SSL-Cert-Subject" in order to
|
---|
| 378 | make the request conditional on the content of the server certificate.
|
---|
| 379 | If the certificate subject does not match, no request is sent to the
|
---|
| 380 | server and an internally generated error response is returned. The
|
---|
| 381 | value of the "If-SSL-Cert-Subject" header is interpreted as a Perl
|
---|
| 382 | regular expression.
|
---|
| 383 |
|
---|
| 384 |
|
---|
| 385 | =head2 FTP Requests
|
---|
| 386 |
|
---|
| 387 | The library currently supports GET, HEAD and PUT requests. GET
|
---|
| 388 | retrieves a file or a directory listing from an FTP server. PUT
|
---|
| 389 | stores a file on a ftp server.
|
---|
| 390 |
|
---|
| 391 | You can specify a ftp account for servers that want this in addition
|
---|
| 392 | to user name and password. This is specified by including an "Account"
|
---|
| 393 | header in the request.
|
---|
| 394 |
|
---|
| 395 | User name/password can be specified using basic authorization or be
|
---|
| 396 | encoded in the URL. Failed logins return an UNAUTHORIZED response with
|
---|
| 397 | "WWW-Authenticate: Basic" and can be treated like basic authorization
|
---|
| 398 | for HTTP.
|
---|
| 399 |
|
---|
| 400 | The library supports ftp ASCII transfer mode by specifying the "type=a"
|
---|
| 401 | parameter in the URL. It also supports transfer of ranges for FTP transfers
|
---|
| 402 | using the "Range" header.
|
---|
| 403 |
|
---|
| 404 | Directory listings are by default returned unprocessed (as returned
|
---|
| 405 | from the ftp server) with the content media type reported to be
|
---|
| 406 | "text/ftp-dir-listing". The C<File::Listing> module provides methods
|
---|
| 407 | for parsing of these directory listing.
|
---|
| 408 |
|
---|
| 409 | The ftp module is also able to convert directory listings to HTML and
|
---|
| 410 | this can be requested via the standard HTTP content negotiation
|
---|
| 411 | mechanisms (add an "Accept: text/html" header in the request if you
|
---|
| 412 | want this).
|
---|
| 413 |
|
---|
| 414 | For normal file retrievals, the "Content-Type" is guessed based on the
|
---|
| 415 | file name suffix. See L<LWP::MediaTypes>.
|
---|
| 416 |
|
---|
| 417 | The "If-Modified-Since" request header works for servers that implement
|
---|
| 418 | the MDTM command. It will probably not work for directory listings though.
|
---|
| 419 |
|
---|
| 420 | Example:
|
---|
| 421 |
|
---|
| 422 | $req = HTTP::Request->new(GET => 'ftp://me:[email protected]/');
|
---|
| 423 | $req->header(Accept => "text/html, */*;q=0.1");
|
---|
| 424 |
|
---|
| 425 | =head2 News Requests
|
---|
| 426 |
|
---|
| 427 | Access to the USENET News system is implemented through the NNTP
|
---|
| 428 | protocol. The name of the news server is obtained from the
|
---|
| 429 | NNTP_SERVER environment variable and defaults to "news". It is not
|
---|
| 430 | possible to specify the hostname of the NNTP server in news: URLs.
|
---|
| 431 |
|
---|
| 432 | The library supports GET and HEAD to retrieve news articles through the
|
---|
| 433 | NNTP protocol. You can also post articles to newsgroups by using
|
---|
| 434 | (surprise!) the POST method.
|
---|
| 435 |
|
---|
| 436 | GET on newsgroups is not implemented yet.
|
---|
| 437 |
|
---|
| 438 | Examples:
|
---|
| 439 |
|
---|
| 440 | $req = HTTP::Request->new(GET => 'news:[email protected]');
|
---|
| 441 |
|
---|
| 442 | $req = HTTP::Request->new(POST => 'news:comp.lang.perl.test');
|
---|
| 443 | $req->header(Subject => 'This is a test',
|
---|
| 444 | From => '[email protected]');
|
---|
| 445 | $req->content(<<EOT);
|
---|
| 446 | This is the content of the message that we are sending to
|
---|
| 447 | the world.
|
---|
| 448 | EOT
|
---|
| 449 |
|
---|
| 450 |
|
---|
| 451 | =head2 Gopher Request
|
---|
| 452 |
|
---|
| 453 | The library supports the GET and HEAD methods for gopher requests. All
|
---|
| 454 | request header values are ignored. HEAD cheats and returns a
|
---|
| 455 | response without even talking to server.
|
---|
| 456 |
|
---|
| 457 | Gopher menus are always converted to HTML.
|
---|
| 458 |
|
---|
| 459 | The response "Content-Type" is generated from the document type
|
---|
| 460 | encoded (as the first letter) in the request URL path itself.
|
---|
| 461 |
|
---|
| 462 | Example:
|
---|
| 463 |
|
---|
| 464 | $req = HTTP::Request->new(GET => 'gopher://gopher.sn.no/');
|
---|
| 465 |
|
---|
| 466 |
|
---|
| 467 |
|
---|
| 468 | =head2 File Request
|
---|
| 469 |
|
---|
| 470 | The library supports GET and HEAD methods for file requests. The
|
---|
| 471 | "If-Modified-Since" header is supported. All other headers are
|
---|
| 472 | ignored. The I<host> component of the file URL must be empty or set
|
---|
| 473 | to "localhost". Any other I<host> value will be treated as an error.
|
---|
| 474 |
|
---|
| 475 | Directories are always converted to an HTML document. For normal
|
---|
| 476 | files, the "Content-Type" and "Content-Encoding" in the response are
|
---|
| 477 | guessed based on the file suffix.
|
---|
| 478 |
|
---|
| 479 | Example:
|
---|
| 480 |
|
---|
| 481 | $req = HTTP::Request->new(GET => 'file:/etc/passwd');
|
---|
| 482 |
|
---|
| 483 |
|
---|
| 484 | =head2 Mailto Request
|
---|
| 485 |
|
---|
| 486 | You can send (aka "POST") mail messages using the library. All
|
---|
| 487 | headers specified for the request are passed on to the mail system.
|
---|
| 488 | The "To" header is initialized from the mail address in the URL.
|
---|
| 489 |
|
---|
| 490 | Example:
|
---|
| 491 |
|
---|
| 492 | $req = HTTP::Request->new(POST => 'mailto:[email protected]');
|
---|
| 493 | $req->header(Subject => "subscribe");
|
---|
| 494 | $req->content("Please subscribe me to the libwww-perl mailing list!\n");
|
---|
| 495 |
|
---|
| 496 | =head2 CPAN Requests
|
---|
| 497 |
|
---|
| 498 | URLs with scheme C<cpan:> are redirected to the a suitable CPAN
|
---|
| 499 | mirror. If you have your own local mirror of CPAN you might tell LWP
|
---|
| 500 | to use it for C<cpan:> URLs by an assignment like this:
|
---|
| 501 |
|
---|
| 502 | $LWP::Protocol::cpan::CPAN = "file:/local/CPAN/";
|
---|
| 503 |
|
---|
| 504 | Suitable CPAN mirrors are also picked up from the configuration for
|
---|
| 505 | the CPAN.pm, so if you have used that module a suitable mirror should
|
---|
| 506 | be picked automatically. If neither of these apply, then a redirect
|
---|
| 507 | to the generic CPAN http location is issued.
|
---|
| 508 |
|
---|
| 509 | Example request to download the newest perl:
|
---|
| 510 |
|
---|
| 511 | $req = HTTP::Request->new(GET => "cpan:src/latest.tar.gz");
|
---|
| 512 |
|
---|
| 513 |
|
---|
| 514 | =head1 OVERVIEW OF CLASSES AND PACKAGES
|
---|
| 515 |
|
---|
| 516 | This table should give you a quick overview of the classes provided by the
|
---|
| 517 | library. Indentation shows class inheritance.
|
---|
| 518 |
|
---|
| 519 | LWP::MemberMixin -- Access to member variables of Perl5 classes
|
---|
| 520 | LWP::UserAgent -- WWW user agent class
|
---|
| 521 | LWP::RobotUA -- When developing a robot applications
|
---|
| 522 | LWP::Protocol -- Interface to various protocol schemes
|
---|
| 523 | LWP::Protocol::http -- http:// access
|
---|
| 524 | LWP::Protocol::file -- file:// access
|
---|
| 525 | LWP::Protocol::ftp -- ftp:// access
|
---|
| 526 | ...
|
---|
| 527 |
|
---|
| 528 | LWP::Authen::Basic -- Handle 401 and 407 responses
|
---|
| 529 | LWP::Authen::Digest
|
---|
| 530 |
|
---|
| 531 | HTTP::Headers -- MIME/RFC822 style header (used by HTTP::Message)
|
---|
| 532 | HTTP::Message -- HTTP style message
|
---|
| 533 | HTTP::Request -- HTTP request
|
---|
| 534 | HTTP::Response -- HTTP response
|
---|
| 535 | HTTP::Daemon -- A HTTP server class
|
---|
| 536 |
|
---|
| 537 | WWW::RobotRules -- Parse robots.txt files
|
---|
| 538 | WWW::RobotRules::AnyDBM_File -- Persistent RobotRules
|
---|
| 539 |
|
---|
| 540 | Net::HTTP -- Low level HTTP client
|
---|
| 541 |
|
---|
| 542 | The following modules provide various functions and definitions.
|
---|
| 543 |
|
---|
| 544 | LWP -- This file. Library version number and documentation.
|
---|
| 545 | LWP::MediaTypes -- MIME types configuration (text/html etc.)
|
---|
| 546 | LWP::Simple -- Simplified procedural interface for common functions
|
---|
| 547 | HTTP::Status -- HTTP status code (200 OK etc)
|
---|
| 548 | HTTP::Date -- Date parsing module for HTTP date formats
|
---|
| 549 | HTTP::Negotiate -- HTTP content negotiation calculation
|
---|
| 550 | File::Listing -- Parse directory listings
|
---|
| 551 | HTML::Form -- Processing for <form>s in HTML documents
|
---|
| 552 |
|
---|
| 553 |
|
---|
| 554 | =head1 MORE DOCUMENTATION
|
---|
| 555 |
|
---|
| 556 | All modules contain detailed information on the interfaces they
|
---|
| 557 | provide. The L<lwpcook> manpage is the libwww-perl cookbook that contain
|
---|
| 558 | examples of typical usage of the library. You might want to take a
|
---|
[27183] | 559 | look at how the scripts L<lwp-request>, L<lwp-rget> and L<lwp-mirror>
|
---|
| 560 | are implemented.
|
---|
[27174] | 561 |
|
---|
| 562 | =head1 ENVIRONMENT
|
---|
| 563 |
|
---|
| 564 | The following environment variables are used by LWP:
|
---|
| 565 |
|
---|
| 566 | =over
|
---|
| 567 |
|
---|
| 568 | =item HOME
|
---|
| 569 |
|
---|
| 570 | The C<LWP::MediaTypes> functions will look for the F<.media.types> and
|
---|
| 571 | F<.mime.types> files relative to you home directory.
|
---|
| 572 |
|
---|
| 573 | =item http_proxy
|
---|
| 574 |
|
---|
| 575 | =item ftp_proxy
|
---|
| 576 |
|
---|
| 577 | =item xxx_proxy
|
---|
| 578 |
|
---|
| 579 | =item no_proxy
|
---|
| 580 |
|
---|
| 581 | These environment variables can be set to enable communication through
|
---|
| 582 | a proxy server. See the description of the C<env_proxy> method in
|
---|
| 583 | L<LWP::UserAgent>.
|
---|
| 584 |
|
---|
[27183] | 585 | =item PERL_LWP_USE_HTTP_10
|
---|
[27174] | 586 |
|
---|
[27183] | 587 | Enable the old HTTP/1.0 protocol driver instead of the new HTTP/1.1
|
---|
| 588 | driver. You might want to set this to a TRUE value if you discover
|
---|
| 589 | that your old LWP applications fails after you installed LWP-5.60 or
|
---|
| 590 | better.
|
---|
[27174] | 591 |
|
---|
| 592 | =item PERL_HTTP_URI_CLASS
|
---|
| 593 |
|
---|
| 594 | Used to decide what URI objects to instantiate. The default is C<URI>.
|
---|
| 595 | You might want to set it to C<URI::URL> for compatibility with old times.
|
---|
| 596 |
|
---|
| 597 | =back
|
---|
| 598 |
|
---|
| 599 | =head1 AUTHORS
|
---|
| 600 |
|
---|
| 601 | LWP was made possible by contributions from Adam Newby, Albert
|
---|
| 602 | Dvornik, Alexandre Duret-Lutz, Andreas Gustafsson, Andreas König,
|
---|
| 603 | Andrew Pimlott, Andy Lester, Ben Coleman, Benjamin Low, Ben Low, Ben
|
---|
| 604 | Tilly, Blair Zajac, Bob Dalgleish, BooK, Brad Hughes, Brian
|
---|
| 605 | J. Murrell, Brian McCauley, Charles C. Fu, Charles Lane, Chris Nandor,
|
---|
| 606 | Christian Gilmore, Chris W. Unger, Craig Macdonald, Dale Couch, Dan
|
---|
| 607 | Kubb, Dave Dunkin, Dave W. Smith, David Coppit, David Dick, David
|
---|
| 608 | D. Kilzer, Doug MacEachern, Edward Avis, erik, Gary Shea, Gisle Aas,
|
---|
| 609 | Graham Barr, Gurusamy Sarathy, Hans de Graaff, Harald Joerg, Harry
|
---|
| 610 | Bochner, Hugo, Ilya Zakharevich, INOUE Yoshinari, Ivan Panchenko, Jack
|
---|
| 611 | Shirazi, James Tillman, Jan Dubois, Jared Rhine, Jim Stern, Joao
|
---|
| 612 | Lopes, John Klar, Johnny Lee, Josh Kronengold, Josh Rai, Joshua
|
---|
| 613 | Chamas, Joshua Hoblitt, Kartik Subbarao, Keiichiro Nagano, Ken
|
---|
| 614 | Williams, KONISHI Katsuhiro, Lee T Lindley, Liam Quinn, Marc Hedlund,
|
---|
| 615 | Marc Langheinrich, Mark D. Anderson, Marko Asplund, Mark Stosberg,
|
---|
| 616 | Markus B KrÃŒger, Markus Laker, Martijn Koster, Martin Thurn, Matthew
|
---|
| 617 | Eldridge, Matthew.van.Eerde, Matt Sergeant, Michael A. Chase, Michael
|
---|
| 618 | Quaranta, Michael Thompson, Mike Schilli, Moshe Kaminsky, Nathan
|
---|
| 619 | Torkington, Nicolai Langfeldt, Norton Allen, Olly Betts, Paul
|
---|
| 620 | J. Schinder, peterm, Philip GuentherDaniel Buenzli, Pon Hwa Lin,
|
---|
| 621 | Radoslaw Zielinski, Radu Greab, Randal L. Schwartz, Richard Chen,
|
---|
| 622 | Robin Barker, Roy Fielding, Sander van Zoest, Sean M. Burke,
|
---|
| 623 | shildreth, Slaven Rezic, Steve A Fink, Steve Hay, Steven Butler,
|
---|
| 624 | Steve_Kilbane, Takanori Ugai, Thomas Lotterer, Tim Bunce, Tom Hughes,
|
---|
| 625 | Tony Finch, Ville SkyttÀ, Ward Vandewege, William York, Yale Huang,
|
---|
| 626 | and Yitzchak Scott-Thoennes.
|
---|
| 627 |
|
---|
| 628 | LWP owes a lot in motivation, design, and code, to the libwww-perl
|
---|
| 629 | library for Perl4 by Roy Fielding, which included work from Alberto
|
---|
| 630 | Accomazzi, James Casey, Brooks Cutter, Martijn Koster, Oscar
|
---|
| 631 | Nierstrasz, Mel Melchner, Gertjan van Oosten, Jared Rhine, Jack
|
---|
| 632 | Shirazi, Gene Spafford, Marc VanHeyningen, Steven E. Brenner, Marion
|
---|
| 633 | Hakanson, Waldemar Kebsch, Tony Sanders, and Larry Wall; see the
|
---|
| 634 | libwww-perl-0.40 library for details.
|
---|
| 635 |
|
---|
| 636 | =head1 COPYRIGHT
|
---|
| 637 |
|
---|
| 638 | Copyright 1995-2009, Gisle Aas
|
---|
| 639 | Copyright 1995, Martijn Koster
|
---|
| 640 |
|
---|
| 641 | This library is free software; you can redistribute it and/or
|
---|
| 642 | modify it under the same terms as Perl itself.
|
---|
| 643 |
|
---|
| 644 | =head1 AVAILABILITY
|
---|
| 645 |
|
---|
| 646 | The latest version of this library is likely to be available from CPAN
|
---|
| 647 | as well as:
|
---|
| 648 |
|
---|
[27183] | 649 | http://github.com/gisle/libwww-perl
|
---|
[27174] | 650 |
|
---|
| 651 | The best place to discuss this code is on the <[email protected]>
|
---|
| 652 | mailing list.
|
---|
| 653 |
|
---|
| 654 | =cut
|
---|