Cataly...rialize(3pm)

💖 Catalyst::Action::Serialize — bestie edition 💖

okay so real talk, this is Catalyst::Action::Serialize, a Perl manual page from the 3pm section of the perl docs (yes the title got chopped to Cataly...rialize which is honestly so dramatic of it 💅). It does one job and it does it gorgeously: it serializes the body of an HTTP Response. Let's get into it 🦋

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✨ NAME ✨

Catalyst::Action::Serialize — Serialize Data in a Response 🎀

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🌸 SYNOPSIS 🌸

package Foo::Controller::Bar;

__PACKAGE__->config(
    'default'   => 'text/x-yaml',
    'stash_key' => 'rest',
    'map'       => {
        'text/html'          => [ 'View', 'TT', ],
        'text/x-yaml'        => 'YAML',
        'text/x-data-dumper' => [ 'Data::Serializer', 'Data::Dumper' ],
    }
);

sub end :ActionClass('Serialize') {}

like… look at it. that's the whole vibe. you set up a map, you slap :ActionClass('Serialize') on your end method, and the serializing just happens. ate. 🔥

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👑 DESCRIPTION 👑

This action will serialize the body of an HTTP Response. The serializer is selected by introspecting the HTTP Requests content-type header. (so it literally looks at what the client asked for and goes "say less, I got you" 😌)

It requires that your Catalyst controller is properly configured to set up the mapping between Content Type's and Serialization classes. No map, no magic — the configuration is the whole plot, bestie.

The specifics of serializing each content-type is implemented as a plugin to Catalyst::Action::Serialize. So each content type gets its own lil specialist 🤝

Typically, you would use this ActionClass on your end method. However, nothing is stopping you from choosing specific methods to Serialize:

sub foo :Local :ActionClass('Serialize') {
   .. populate stash with data ..
}

main character energy honestly. pick whichever methods you want serialized, it's your world 🌈

When you use this module, the request class will be changed to Catalyst::Request::REST. not a suggestion, that's just what happens 🫶

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💜 CONFIGURATION 💜

🎀 map

Takes a hashref, mapping Content-Types to a given serializer plugin. that's the whole thing. content type in, serializer plugin out 💖

🎀 default

This is the 'fall-back' Content-Type if none of the requested or acceptable types is found in the map. It must be an entry in the map.

⚠️ bestie listen: it must be an entry in the map. don't be out here pointing default at something that isn't in there, okay? 😭

🎀 stash_key

Specifies the key of the stash entry holding the data that is to be serialized. So if the value is rest, we will serialize the data under:

$c->stash->{'rest'}

lowkey the most important setting and everyone forgets it 💀

🎀 content_type_stash_key

Specifies the key of the stash entry that optionally holds an overriding Content-Type. If set, and if the specified stash entry has a valid value, then it takes priority over the requested content types.

This can be useful if you want to dynamically force a particular content type, perhaps for debugging. obsessed with a good override tbh 🙈

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🫶 HELPFUL PEOPLE 🫶

Daisuke Maki pointed out that early versions of this Action did not play well with others, or generally behave in a way that was very consistent with the rest of Catalyst.

(real ones remember. thank you Daisuke, genuinely iconic of you to say something 🙏✨)

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😭 CUSTOM ERRORS 😭

For building custom error responses when serialization fails, you can create an ActionRole (and use Catalyst::Controller::ActionRole to apply it to the end action) which overrides unsupported_media_type and/or serialize_bad_request methods.

so when it all goes sideways — and sometimes it will, no cap — you can build your own cute error responses instead of vibing with the default ones 💅

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🔍 SEE ALSO 🔍

You likely want to look at Catalyst::Controller::REST, which implements a sensible set of defaults for doing a REST controller. fr fr, start there.

Catalyst::Action::Deserialize, Catalyst::Action::REST — the rest of the friend group 🌈

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💖 AUTHORS 💖

See Catalyst::Action::REST for authors. (they're over there, go say hi 👋)

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📜 LICENSE 📜

You may distribute this code under the same terms as Perl itself. slay, generous, we love to see it ✨

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aaaand that's the page!! this was shipped as part of perl v5.40.1, dated 2026-05-07, and it lives in the User Contributed Perl Documentation collection (the 3pm section, iykyk) 💅🌸 mwah, go serialize something gorgeous bestie 🦋💖