Mojo::Headers(3)

📦

version 9.480.0 · 13 versions

9.480.0 · opensuse-leap 16.0 (latest)
9.22 · epel 9
9.39 · epel 10
9.45 · alpine 3.24
9.48 · ubuntu stonking
9.41 · fedora 43
9.22 · ubuntu jammy
9.48 · fedora 43, fedora 44
9.42 · fedora 44
9.35 · ubuntu noble
9.31 · debian bookworm
9.42 · ubuntu resolute
9.39 · debian trixie, ubuntu questing

💖 Mojo::Headers — HTTP headers, but make it cute 💖

(this is the Mojo::Headers(3) perl manual page, bestie, and it's literally all about HTTP headers)

Okay so picture this: you've got HTTP headers. A lot of them. And instead of wrangling them by hand like some sort of feral gremlin, you use Mojo::Headers. It's a whole container for HTTP headers, built on RFC 7230 <https://tools.ietf.org/html/rfc7230> and RFC 7231 <https://tools.ietf.org/html/rfc7231>. No cap, it's giving standards-compliant queen. 👑

✨ SYNOPSIS ✨

use Mojo::Headers;

# Parse
my $headers = Mojo::Headers->new;
$headers->parse("Content-Length: 42\x0d\x0a");
$headers->parse("Content-Type: text/html\x0d\x0a\x0d\x0a");
say $headers->content_length;
say $headers->content_type;

# Build
my $headers = Mojo::Headers->new;
$headers->content_length(42);
$headers->content_type('text/plain');
say $headers->to_string;

Like, look at her go. Parsing in one direction, building in the other, both serving main character energy. 🦋

🌸 DESCRIPTION 🌸

Mojo::Headers is a container for HTTP headers — that's it, that's the vibe. It's based on RFC 7230 <https://tools.ietf.org/html/rfc7230> and RFC 7231 <https://tools.ietf.org/html/rfc7231>, so you know she's been raised right.

🎀 ATTRIBUTES 🎀

Mojo::Headers implements the following attributes. Yes, the word "implements" is doing a lot of work here and we love that for her.

💅 `max_line_size`

my $size = $headers->max_line_size;
$headers = $headers->max_line_size(1024);

Maximum header line size, in bytes, bestie. Important: it defaults to the value of the MOJO_MAX_LINE_SIZE environment variable, or 8192 (8KiB) if that's not set. So like, there's a ceiling and it's 8KiB unless you say otherwise. ✨

💅 `max_lines`

my $num  = $headers->max_lines;
$headers = $headers->max_lines(200);

Maximum number of header lines. Defaults to the value of the MOJO_MAX_LINES environment variable, or 100. So a hundred lines, then the door closes. 🚪

🔥 METHODS 🔥

Mojo::Headers inherits all methods from Mojo::Base (iconic behaviour, tbh) and implements the following new ones.

⭐ `add`

$headers = $headers->add(Foo => 'one value');
$headers = $headers->add(Foo => 'first value', 'second value');

Adds a header with one or more lines. Multiple lines, multiple values, no drama.

# "Vary: Accept
#  Vary: Accept-Encoding"
$headers->add(Vary => 'Accept')->add(Vary => 'Accept-Encoding')->to_string;

See how Vary shows up twice? That's the whole point, bestie — add doesn't merge, it just stacks. 🫶

⭐ `append`

$headers = $headers->append(Vary => 'Accept-Encoding');

Appends a value to a header, and flattens it if it needs flattening. Very "let me just tidy up in here" of her.

# "Vary: Accept"
$headers->append(Vary => 'Accept')->to_string;

# "Vary: Accept, Accept-Encoding"
$headers->vary('Accept')->append(Vary => 'Accept-Encoding')->to_string;

First one: nothing to append to, so it's just a Vary: Accept. Second one: there's already a Vary: Accept, so the two get smooshed into Vary: Accept, Accept-Encoding with a comma. Flattening! Slay. 💐

⭐ `clone`

my $clone = $headers->clone;

Returns a brand new Mojo::Headers object, cloned from these headers. A whole twin. Separate object, same energy. 👯

⭐ `dehop`

$headers = $headers->dehop;

Removes hop-by-hop headers — the ones that should not be retransmitted. Like, they had one hop and now they're done. Bye. 👋

⭐ `every_header`

my $all = $headers->every_header('Location');

Similar to header, but returns all the headers sharing the same name as an array reference. All of them. The whole squad.

# Get first header value
say $headers->every_header('Location')->[0];

That ->[0] is you grabbing the first one out of the array ref. iykyk. 💫

⭐ `from_hash`

$headers = $headers->from_hash({'Cookie' => 'a=b'});
$headers = $headers->from_hash({'Cookie' => ['a=b', 'c=d']});
$headers = $headers->from_hash({});

Parses headers from a hash reference. Pass an array ref and you get multiple values for the same header. Pass an empty hash and it removes all headers — yes, a full reset, she said clear the cache. 🧹

⭐ `header`

my $value = $headers->header('Foo');
$headers  = $headers->header(Foo => 'one value');
$headers  = $headers->header(Foo => 'first value', 'second value');

Gets or replaces the current header values. Read that again: replaces. It's not add, it's not append, it's a takeover. New value, who dis. 👑

⭐ `is_finished`

my $bool = $headers->is_finished;

Checks if the header parser is finished. A yes/no vibe check on your parsing. 🏁

⭐ `is_limit_exceeded`

my $bool = $headers->is_limit_exceeded;

Checks if the headers have exceeded max_line_size or max_lines. Like a bouncer at the club, but for byte counts and line counts. 🚨

⭐ `leftovers`

my $bytes = $headers->leftovers;

Gets and removes leftover data from the header parser. Both things at once. Multitasking queen. 🍓

⭐ `names`

my $names = $headers->names;

Returns an array reference with all currently defined headers. A little roster of everyone who made it in.

# Names of all headers
say for @{$headers->names};

Yep, say for — no braces, no fuss, just printing every name. 💜

⭐ `parse`

$headers = $headers->parse("Content-Type: text/plain\x0d\x0a\x0d\x0a");

Parses formatted headers. Feed her the raw bytes, she'll make sense of it. 🧚

⭐ `remove`

$headers = $headers->remove('Foo');

Removes a header. One header, one clean removal, no collateral damage. ✨

⭐ `to_hash`

my $single = $headers->to_hash;
my $multi  = $headers->to_hash(1);

Turns the headers into a hash reference. Array references — used to represent multiple headers with the same name — are disabled by default. So to_hash on its own gives you one value per name; pass 1 and you get arrays for the multi-value ones. Pick your fighter.

say $headers->to_hash->{DNT};

Look at that direct hash access. Chef's kiss. 🤌

⭐ `to_string`

my $str = $headers->to_string;

Turns the headers into a string, suitable for HTTP messages. Ready to ship, no assembly required. 📦

🌈 ADDITIONAL METHODS 🌈

Also — and this is the good part — the following shortcuts are available, for accessing and manipulating commonly-used headers. Think of them as fast passes. 🎟️

🦋 `accept`

my $accept = $headers->accept;
$headers   = $headers->accept('application/json');

Get or replace the current header value. Shortcut for the Accept header.

🦋 `accept_charset`

my $charset = $headers->accept_charset;
$headers    = $headers->accept_charset('UTF-8');

Get or replace the current header value. Shortcut for the Accept-Charset header.

🦋 `accept_encoding`

my $encoding = $headers->accept_encoding;
$headers     = $headers->accept_encoding('gzip');

Get or replace the current header value. Shortcut for the Accept-Encoding header.

🦋 `accept_language`

my $language = $headers->accept_language;
$headers     = $headers->accept_language('de, en');

Get or replace the current header value. Shortcut for the Accept-Language header.

🦋 `accept_ranges`

my $ranges = $headers->accept_ranges;
$headers   = $headers->accept_ranges('bytes');

Get or replace the current header value. Shortcut for the Accept-Ranges header.

🦋 `access_control_allow_origin`

my $origin = $headers->access_control_allow_origin;
$headers   = $headers->access_control_allow_origin('*');

Get or replace the current header value. Shortcut for the Access-Control-Allow-Origin header from Cross-Origin Resource Sharing <https://www.w3.org/TR/cors/>. CORS said "let her in" 💅

🦋 `allow`

my $allow = $headers->allow;
$headers  = $headers->allow('GET, POST');

Get or replace the current header value. Shortcut for the Allow header.

🦋 `authorization`

my $authorization = $headers->authorization;
$headers          = $headers->authorization('Basic Zm9vOmJhcg==');

Get or replace the current header value. Shortcut for the Authorization header. That base64 is you, don't worry about it. 🙈

🦋 `cache_control`

my $cache_control = $headers->cache_control;
$headers          = $headers->cache_control('max-age=1, no-cache');

Get or replace the current header value. Shortcut for the Cache-Control header.

🦋 `connection`

my $connection = $headers->connection;
$headers       = $headers->connection('close');

Get or replace the current header value. Shortcut for the Connection header.

🦋 `content_disposition`

my $disposition = $headers->content_disposition;
$headers        = $headers->content_disposition('foo');

Get or replace the current header value. Shortcut for the Content-Disposition header.

🦋 `content_encoding`

my $encoding = $headers->content_encoding;
$headers     = $headers->content_encoding('gzip');

Get or replace the current header value. Shortcut for the Content-Encoding header.

🦋 `content_language`

my $language = $headers->content_language;
$headers     = $headers->content_language('en');

Get or replace the current header value. Shortcut for the Content-Language header.

🦋 `content_length`

my $len  = $headers->content_length;
$headers = $headers->content_length(4000);

Get or replace the current header value. Shortcut for the Content-Length header. Note she takes a plain old number here, not a string. 🔢

🦋 `content_location`

my $location = $headers->content_location;
$headers     = $headers->content_location('http://127.0.0.1/foo');

Get or replace the current header value. Shortcut for the Content-Location header.

🦋 `content_range`

my $range = $headers->content_range;
$headers  = $headers->content_range('bytes 2-8/100');

Get or replace the current header value. Shortcut for the Content-Range header.

🦋 `content_security_policy`

my $policy = $headers->content_security_policy;
$headers   = $headers->content_security_policy('default-src https:');

Get or replace the current header value. Shortcut for the Content-Security-Policy header from Content Security Policy 1.0 <https://www.w3.org/TR/CSP/>. Security but make it chic. 🛡️

🦋 `content_type`

my $type = $headers->content_type;
$headers = $headers->content_type('text/plain');

Get or replace the current header value. Shortcut for the Content-Type header.

🦋 `cookie`

my $cookie = $headers->cookie;
$headers   = $headers->cookie('f=b');

Get or replace the current header value. Shortcut for the Cookie header from RFC 6265 <https://tools.ietf.org/html/rfc6265>. 🍪 (sorry, had to)

🦋 `date`

my $date = $headers->date;
$headers = $headers->date('Sun, 17 Aug 2008 16:27:35 GMT');

Get or replace the current header value. Shortcut for the Date header.

🦋 `dnt`

my $dnt  = $headers->dnt;
$headers = $headers->dnt(1);

Get or replace the current header value. Shortcut for the DNT (Do Not Track) header — which, fun fact, has no specification yet but is very commonly used. Iconic for being unspec'd and still booked and busy. ⭐

🦋 `etag`

my $etag = $headers->etag;
$headers = $headers->etag('"abc321"');

Get or replace the current header value. Shortcut for the ETag header. Keep those quotes, bestie, they're part of the string. 💖

🦋 `expect`

my $expect = $headers->expect;
$headers   = $headers->expect('100-continue');

Get or replace the current header value. Shortcut for the Expect header.

🦋 `expires`

my $expires = $headers->expires;
$headers    = $headers->expires('Thu, 01 Dec 1994 16:00:00 GMT');

Get or replace the current header value. Shortcut for the Expires header.

🦋 `host`

my $host = $headers->host;
$headers = $headers->host('127.0.0.1');

Get or replace the current header value. Shortcut for the Host header.

🦋 `if_modified_since`

my $date = $headers->if_modified_since;
$headers = $headers->if_modified_since('Sun, 17 Aug 2008 16:27:35 GMT');

Get or replace the current header value. Shortcut for the If-Modified-Since header.

🦋 `if_none_match`

my $etag = $headers->if_none_match;
$headers = $headers->if_none_match('"abc321"');

Get or replace the current header value. Shortcut for the If-None-Match header.

🦋 `last_modified`

my $date = $headers->last_modified;
$headers = $headers->last_modified('Sun, 17 Aug 2008 16:27:35 GMT');

Get or replace the current header value. Shortcut for the Last-Modified header.

🦋 `link`

my $link = $headers->link;
$headers = $headers->link('<http://127.0.0.1/foo/3>; rel="next"');

Get or replace the current header value. Shortcut for the Link header from RFC 5988 <https://tools.ietf.org/html/rfc5988>.

🦋 `links`

my $links = $headers->links;
$headers  = $headers->links({next => 'http://example.com/foo', prev => 'http://example.com/bar'});

Get or set web links from or to the Link header, according to RFC 5988 <http://tools.ietf.org/html/rfc5988>. (Note: this one's the http:// link, not https:// — don't come for me, that's literally what the page says. 👀)

# Extract information about next page
say $headers->links->{next}{link};
say $headers->links->{next}{title};

So you can pull out, like, the actual link and the title of the next page. Little nuggets of info. 🎀

🦋 `location`

my $location = $headers->location;
$headers     = $headers->location('http://127.0.0.1/foo');

Get or replace the current header value. Shortcut for the Location header.

🦋 `origin`

my $origin = $headers->origin;
$headers   = $headers->origin('http://example.com');

Get or replace the current header value. Shortcut for the Origin header from RFC 6454 <https://tools.ietf.org/html/rfc6454>.

(and there's like, way more of this page coming — don't go anywhere 💀)

`proxy_authenticate`

my $authenticate = $headers->proxy_authenticate;
$headers         = $headers->proxy_authenticate('Basic "realm"');

Get or replace the current header value bestie — it's a shortcut for the Proxy-Authenticate header. 💅

`proxy_authorization`

my $authorization = $headers->proxy_authorization;
$headers          = $headers->proxy_authorization('Basic Zm9vOmJhcg==');

Get or replace the current header value — shortcut for the Proxy-Authorization header, slay. ✨

`range`

my $range = $headers->range;
$headers  = $headers->range('bytes=2-8');

Get or replace the current header value — shortcut for the Range header. Obsessed with how simple that is fr. 🎀

`referer`

my $referrer = $headers->referer;
$headers     = $headers->referer('http://example.com');

Alias for referrer. Just a little twin situation, no cap. 🦋

`referrer`

my $referrer = $headers->referrer;
$headers     = $headers->referrer('http://example.com');

Get or replace the current header value — shortcut for the Referer header. And okay, story time: there was a typo in RFC 2068 <https://tools.ietf.org/html/rfc2068> which resulted in Referer becoming an official header. Iconic typo behavior honestly, it ate and now it's canon. 😭👑

`sec_websocket_accept`

my $accept = $headers->sec_websocket_accept;
$headers   = $headers->sec_websocket_accept('s3pPLMBiTxaQ9kYGzzhZRbK+xOo=');

Get or replace the current header value — shortcut for the Sec-WebSocket-Accept header from RFC 6455 <https://tools.ietf.org/html/rfc6455>. 🌈

`sec_websocket_extensions`

my $extensions = $headers->sec_websocket_extensions;
$headers       = $headers->sec_websocket_extensions('foo');

Get or replace the current header value — shortcut for the Sec-WebSocket-Extensions header from RFC 6455 <https://tools.ietf.org/html/rfc6455>. ✨

`sec_websocket_key`

my $key  = $headers->sec_websocket_key;
$headers = $headers->sec_websocket_key('dGhlIHNhbXBsZSBub25jZQ==');

Get or replace the current header value — shortcut for the Sec-WebSocket-Key header from RFC 6455 <https://tools.ietf.org/html/rfc6455>. 🔑

`sec_websocket_protocol`

my $proto = $headers->sec_websocket_protocol;
$headers  = $headers->sec_websocket_protocol('sample');

Get or replace the current header value — shortcut for the Sec-WebSocket-Protocol header from RFC 6455 <https://tools.ietf.org/html/rfc6455>. 🧚

`sec_websocket_version`

my $version = $headers->sec_websocket_version;
$headers    = $headers->sec_websocket_version(13);

Get or replace the current header value — shortcut for the Sec-WebSocket-Version header from RFC 6455 <https://tools.ietf.org/html/rfc6455>. 💜

`server`

my $server = $headers->server;
$headers   = $headers->server('Mojo');

Get or replace the current header value — shortcut for the Server header. Main character header energy tbh. 👑

`server_timing`

my $timing = $headers->server_timing;
$headers   = $headers->server_timing('app;desc=Mojolicious;dur=0.0001');

Get or replace the current header value — shortcut for the Server-Timing header from Server Timing <https://www.w3.org/TR/server-timing/>. ⏱️

`set_cookie`

my $cookie = $headers->set_cookie;
$headers   = $headers->set_cookie('f=b; path=/');

Get or replace the current header value — shortcut for the Set-Cookie header from RFC 6265 <https://tools.ietf.org/html/rfc6265>. 🍪

`status`

my $status = $headers->status;
$headers   = $headers->status('200 OK');

Get or replace the current header value — shortcut for the Status header from RFC 3875 <https://tools.ietf.org/html/rfc3875>. 💖

`strict_transport_security`

my $policy = $headers->strict_transport_security;
$headers   = $headers->strict_transport_security('max-age=31536000');

Get or replace the current header value — shortcut for the Strict-Transport-Security header from RFC 6797 <https://tools.ietf.org/html/rfc6797>. Security bestie behavior, we love to see it. 🔥

`te`

my $te   = $headers->te;
$headers = $headers->te('chunked');

Get or replace the current header value — shortcut for the TE header. ✨

`trailer`

my $trailer = $headers->trailer;
$headers    = $headers->trailer('X-Foo');

Get or replace the current header value — shortcut for the Trailer header. 🎬

`transfer_encoding`

my $encoding = $headers->transfer_encoding;
$headers     = $headers->transfer_encoding('chunked');

Get or replace the current header value — shortcut for the Transfer-Encoding header. 🦋

`upgrade`

my $upgrade = $headers->upgrade;
$headers    = $headers->upgrade('websocket');

Get or replace the current header value — shortcut for the Upgrade header. Glow-up header, literally. ⭐

`user_agent`

my $agent = $headers->user_agent;
$headers  = $headers->user_agent('Mojo/1.0');

Get or replace the current header value — shortcut for the User-Agent header. 🌸

`vary`

my $vary = $headers->vary;
$headers = $headers->vary('*');

Get or replace the current header value — shortcut for the Vary header. 🎀

`www_authenticate`

my $authenticate = $headers->www_authenticate;
$headers         = $headers->www_authenticate('Basic realm="realm"');

Get or replace the current header value — shortcut for the WWW-Authenticate header. 💅

🌈 SEE ALSO 🌈

Mojolicious
Mojolicious::Guides
<https://mojolicious.org>

And that's the whole page bestie, you made it to the end! 🫶 This little masterpiece is Mojo::Headers(3), from perl v5.42.0, dated 2026-07-15. Go forth and set some headers, you absolute icon. 💖✨

📦 where this page comes from

opensuse-leap 16.0: perl-Mojolicious 9.480.0-bp160.2.1 · Artistic-2.0
💖 girlified by deepseek-ai/DeepSeek-V4.1-Flash-1017 on 2026-11-04: a language model's rewrite of the original, under its terms

Mojo::Headers(3)

💖 Mojo::Headers — HTTP headers, but make it cute 💖

✨ SYNOPSIS ✨

🌸 DESCRIPTION 🌸

🎀 ATTRIBUTES 🎀

💅 max_line_size

💅 max_lines

🔥 METHODS 🔥

⭐ add

⭐ append

⭐ clone

⭐ dehop

⭐ every_header

⭐ from_hash

⭐ header

⭐ is_finished

⭐ is_limit_exceeded

⭐ leftovers

⭐ names

⭐ parse

⭐ remove

⭐ to_hash

⭐ to_string

🌈 ADDITIONAL METHODS 🌈

🦋 accept

🦋 accept_charset

🦋 accept_encoding

🦋 accept_language

🦋 accept_ranges

🦋 access_control_allow_origin

🦋 allow

🦋 authorization

🦋 cache_control

🦋 connection

🦋 content_disposition

🦋 content_encoding

🦋 content_language

🦋 content_length

🦋 content_location

🦋 content_range

🦋 content_security_policy

🦋 content_type

🦋 cookie

🦋 date

🦋 dnt

🦋 etag

🦋 expect

🦋 expires

🦋 host

🦋 if_modified_since

🦋 if_none_match

🦋 last_modified

🦋 link

🦋 links

🦋 location

🦋 origin

proxy_authenticate

proxy_authorization

range

referer

referrer

sec_websocket_accept

sec_websocket_extensions

sec_websocket_key

sec_websocket_protocol

sec_websocket_version

server

server_timing

set_cookie

status

strict_transport_security

te

trailer

transfer_encoding

upgrade

user_agent

vary

www_authenticate