HTTP::H...rs::Util(3)

💖 NAME 💖

ok so bestie, HTTP::Headers::Util — it's header value parsing utility functions. that's the whole vibe. it parses HTTP header values and helps you build valid ones back up. periodt. ✨

🌸 VERSION 🌸

this is version 7.03 🎀

🦋 SYNOPSIS 🦋

ok so here's the whole entire vibe in two lines, look:

use HTTP::Headers::Util qw(split_header_words);
@values = split_header_words($h->header("Content-Type"));

that's it. that's the tea. 💅

✨ DESCRIPTION ✨

so this module is literally just a lil collection of functions that help you parse and construct valid HTTP header values. and listen — none of these functions get exported by default, so you gotta ask for them by name, okay? no sneaky auto-importing here. 🙈

here's what's available, bestie:

💜 split_header_words( @header_values )

ok so this one takes the header values you pass it as arguments and parses them into a list of anonymous arrays containing key/value pairs. it knows how to deal with ",", ";" and "=", and it also handles quoted values that come after "=". and here's a fun one — a list of space separated tokens gets parsed as if they were separated by ";". slay. 🔥

and if the @header_values you pass in contains multiple values? they get treated like they were one single value separated by a comma ",". iconic.

so basically this function is your girl for parsing header fields that follow this syntax here (BNF straight from the HTTP/1.1 spec, except we relax the requirement for tokens — we're chill like that):

headers           = #header
header            = (token | parameter) *( [";"] (token | parameter))

token             = 1*<any CHAR except CTLs or separators>
separators        = "(" | ")" | "<" | ">" | "@"
                  | "," | ";" | ":" | "\" | <">
                  | "/" | "[" | "]" | "?" | "="
                  | "{" | "}" | SP | HT

quoted-string     = ( <"> *(qdtext | quoted-pair ) <"> )
qdtext            = <any TEXT except <">>
quoted-pair       = "\" CHAR

parameter         = attribute "=" value
attribute         = token
value             = token | quoted-string

each header gets represented by an anonymous array of key/value pairs. the keys are all forced to lower case. and the value for a simple token (like, one that's not part of a parameter) is undef. also ngl, syntactically incorrect headers will not necessarily be parsed the way you'd want them to be — so don't come for her if your garbage input gives garbage output. 💀

ok this is way easier to show than to explain, so examples, bestie:

split_header_words('foo="bar"; port="80,81"; DISCARD, BAR=baz');
split_header_words('text/html; charset="iso-8859-1"');
split_header_words('Basic realm="\\"foo\\\\bar\\""');

and those return:

[foo=>'bar', port=>'80,81', discard=> undef], [bar=>'baz' ]
['text/html' => undef, charset => 'iso-8859-1']
[basic => undef, realm => "\"foo\\bar\""]

and OMG here's a secret — if you do not want the function converting tokens and attribute keys to lower case, just call it as _split_header_words instead (yeah, with a leading underscore 👀). lowercase is cancelled, we're going full caps now. 💅

💖 join_header_words( @arrays )

this one does the exact opposite of what split_header_words() does. she takes a list of anonymous arrays as arguments (or honestly, a plain list of key/value pairs works too) and produces a single header value. attribute values get quoted if they need it. no cap. ✨

example time:

join_header_words(["text/plain" => undef, charset => "iso-8859/1"]);
join_header_words("text/plain" => undef, charset => "iso-8859/1");

both of those return this string right here:

text/plain; charset="iso-8859/1"

see? symmetrical. the way that she just reverses everything. obsessed. 🫶

👑 AUTHOR 👑

Gisle Aas <gisle@activestate.com> — the icon, the moment, the legend. 🌈

🎀 COPYRIGHT AND LICENSE 🎀

this software is copyright (c) 1994 by Gisle Aas.

and it's free software, bestie — you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself. free as in freedom, fr fr. 🦋

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💌 okay that's the whole page!! this was HTTP::H...rs::Util(3) from User Contributed Perl Documentation, rendered on 2026-07-23 with perl v5.42.2. tysm for reading, go parse some headers, ily, bye bestie!! 💖✨🎀🫶