HTTP::Response(3)

NAME
HTTP::Response - HTTP style response message

SYNOPSIS
Response objects are returned by the request() method of the "LWP::UserAgent":

    # ...
    $response = $ua->request($request)
    if ($response->is_success) {
        print $response->content;
    }
    else {
        print STDERR $response->status_line, "\n";
    }

DESCRIPTION
The "HTTP::Response" class encapsulates HTTP style responses. A response consists of a response line, some headers, and a content body. Note that the LWP library uses HTTP style responses even for non-HTTP protocol schemes. Instances of this class are usually created and returned by the request() method of an "LWP::UserAgent" object.

"HTTP::Response" is a subclass of "HTTP::Message" and therefore inherits its methods. The following additional methods are available:

$r = HTTP::Response->new( $code )
$r = HTTP::Response->new( $code, $msg )
$r = HTTP::Response->new( $code, $msg, $header )
$r = HTTP::Response->new( $code, $msg, $header, $content )
    Constructs a new "HTTP::Response" object describing a response with response code $code and optional message $msg. The optional $header argument should be a reference to an "HTTP::Headers" object. The optional $content argument should be a string of bytes. The meaning these arguments are described below.

$r->code
$r->code( $code )
    This is used to get/set the code attribute. The code is a 3 digit number that encode the overall outcome of a HTTP response. The "HTTP::Status" module provide constants that provide mnemonic names for the code attribute.

$r->message
$r->message( $message )
    This is used to get/set the message attribute. The message is a short human readable single line string that explains the response code.

$r->header( $field )
$r->header( $field => $value )
    This is used to get/set header values and it is inherited from "HTTP::Headers" via "HTTP::Message". See HTTP::Headers for details and other similar methods that can be used to access the headers.

$r->content
$r->content( $content )
    This is used to get/set the content and it is inherited from the "HTTP::Message" base class. See HTTP::Message for details and other methods that can be used to access the content.

$r->request
$r->request( $request )
    This is used to get/set the request attribute. The request attribute is a reference to the the request that caused this response. It does not have to be the same request passed to the $ua->request() method, because there might have been redirects and authorization retries in between.

$r->previous
$r->previous( $response )
    This is used to get/set the previous attribute. The previous attribute is used to link together chains of responses. You get chains of responses if the first response is redirect or unauthorized. The value is "undef" if this is the first response in a chain.

$r->status_line
    Returns the string "<code> <message>". If the message attribute is not set then the official name of <code> (see HTTP::Status) is substituted.

$r->base
    Returns the base URI for this response. The return value will be a reference to a URI object.

    The base URI is obtained from one the following sources (in priority order):

    1.  Embedded in the document content, for instance <BASE HREF="..."> in HTML documents.

    2.  A "Content-Base:" or a "Content-Location:" header in the response.

        For backwards compatability with older HTTP implementations we will also look for the "Base:" header.

    3.  The URI used to request this response. This might not be the original URI that was passed to $ua->request() method, because we might have received some redirect responses first.

    When the LWP protocol modules produce the HTTP::Response object, then any base URI embedded in the document (step 1) will already have initialized the "Content-Base:" header. This means that this method only performs the last 2 steps (the content is not always available either).

$r->as_string
    Returns a textual representation of the response. Mainly useful for debugging purposes. It takes no arguments.

$r->is_info
$r->is_success
$r->is_redirect
$r->is_error
    These methods indicate if the response was informational, sucessful, a redirection, or an error. See HTTP::Status for the meaning of these.

$r->error_as_HTML
    Returns a string containing a complete HTML document indicating what error occurred. This method should only be called when $r->is_error is TRUE.

$r->current_age
    Calculates the "current age" of the response as specified by RFC 2616 section 13.2.3. The age of a response is the time since it was sent by the origin server. The returned value is a number representing the age in seconds.

$r->freshness_lifetime
    Calculates the "freshness lifetime" of the response as specified by RFC 2616 section 13.2.4. The "freshness lifetime" is the length of time between the generation of a response and its expiration time. The returned value is a number representing the freshness lifetime in seconds.

    If the response does not contain an "Expires" or a "Cache-Control" header, then this function will apply some simple heuristic based on 'Last-Modified' to determine a suitable lifetime.

$r->is_fresh
    Returns TRUE if the response is fresh, based on the values of freshness_lifetime() and current_age(). If the response is no longer fresh, then it has to be refetched or revalidated by the origin server.

$r->fresh_until
    Returns the time when this entiy is no longer fresh.

SEE ALSO
HTTP::Headers, HTTP::Message, HTTP::Status, HTTP::Request

COPYRIGHT
Copyright 1995-2001 Gisle Aas.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.