choose a variant to serve
This module provides a complete implementation of the HTTP content
negotiation algorithm specified in _draft-ietf-http-v11-spec-00.ps_ chapter
12. Content negotiation allows for the selection of a preferred content
representation based upon attributes of the negotiable variants and the
value of the various Accept* header fields in the request.
The variants are ordered by preference by calling the function choose().
The first parameter is reference to an array of the variants to choose
among. Each element in this array is an array with the values [$id, $qs,
$content_type, $content_encoding, $charset, $content_language,
$content_length] whose meanings are described below. The $content_encoding
and $content_language can be either a single scalar value or an array
reference if there are several values.
The second optional parameter is either a HTTP::Headers or a HTTP::Request
object which is searched for "Accept*" headers. If this parameter is
missing, then the accept specification is initialized from the CGI
environment variables HTTP_ACCEPT, HTTP_ACCEPT_CHARSET,
HTTP_ACCEPT_ENCODING and HTTP_ACCEPT_LANGUAGE.
In an array context, choose() returns a list of [variant identifier,
calculated quality, size] tuples. The values are sorted by quality, highest
quality first. If the calculated quality is the same for two variants, then
they are sorted by size (smallest first). _E.g._:
(['var1', 1, 2000], ['var2', 0.3, 512], ['var3', 0.3, 1024]);
Note that also zero quality variants are included in the return list even
if these should never be served to the client.
In a scalar context, it returns the identifier of the variant with the
highest score or 'undef' if none have non-zero quality.
If the $HTTP::Negotiate::DEBUG variable is set to TRUE, then a lot of noise
is generated on STDOUT during evaluation of choose().
There is no official package available for openSUSE Leap 15.4