Dancer...Mutable(3pm)

💖 Dancer::Serializer::Mutable 💖

okay bestie, welcome to Dancer::Serializer::Mutable (yes that's the full name, she's from the Dancer::Serializer family, and she's a 3pm perl module 💅). She's the one who figures out what format your content should be in, then serializes and deserializes it using the appropriate HTTP header. no cap. ✨

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🌸 VERSION 🌸

so this is version 1.3522 🎀

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✨ SYNOPSIS ✨

okay so here's the whole vibe:

# in config.yml
serializer: Mutable

# in the app
put '/something' => sub {
    # deserialized from request
    my $name = param( 'name' );

    ...

    # will be serialized to the most
    # fitting format
    return { message => "user $name added" };
};

that's literally it. you set it in config.yml, you go about your business, and she handles the rest 🫶

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💫 DESCRIPTION 💫

so what she does is, she tries to find the best (de)serializer for any given request 🦋. to do that, she goes down this list and picks the first content type she finds, then uses its related serializer:

• the content_type from the request headers
• the content_type parameter from the URL
• the accept from the request headers
• and if nothing else shows up, the default is application/json

and here's the content-type to serializer mapping that Dancer::Serializer::Mutable uses, bestie, look at her:

serializer               | content types
----------------------------------------------------------
Dancer::Serializer::YAML | text/x-yaml, text/html
Dancer::Serializer::XML  | text/xml
Dancer::Serializer::JSON | text/x-json, application/json

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🎀 EXPORTABLE FUNCTIONS 🎀

🌈 template_or_serialize( $template, $data, $options ) 🌈

for those moments when you want to render a template for normal browser requests, but return serialized content for AJAX calls. two moods, one function, iconic 🧚

if the requested content-type is text/html, template_or_serialize returns the rendered template. otherwise it returns $data unmodified — and then that gets serialized as usual 💜

heads up: template_or_serialize is not exported by default. so you gotta ask for her by name, like:

use Dancer::Serializer::Mutable qw/ template_or_serialize /;

get '/greetings' => sub {
    ...;

    return template_or_serialize 'greetings' => {
        title => $title,
        name  => $name,
    };
};

slay 🍓

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🔥 INTERNAL METHODS 🔥

these are the methods that Dancer uses internally, and they are not accessible via the DSL. so like, you can look, but they're not for you to call directly, iykyk 🙈

⭐ serialize

serialize a data structure ✨. the format she serializes it to is determined automatically, as described above 👆. it can be one of YAML, XML… wait, YAML, XML, JSON — and she defaults to JSON if there's no clear preference from the request 💅

⭐ deserialize

deserialize the provided serialized data into a data structure 💖. the type of serialization format depends on the request's content-type. for now, it can be one of YAML, XML, JSON 🌈

⭐ content_type

returns the content-type that was used during the last serialize / deserialize call 🎀

⚠️ WARNING: you must call serialize / deserialize before calling content_type. otherwise the return value will be undef 💀

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🫶 AUTHOR 🫶

Dancer Core Developers — legends, honestly 👑

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💜 COPYRIGHT AND LICENSE 💜

this software is copyright (c) 2010 by Alexis Sukrieh 🌸

this is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself ✨

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and that's the whole page, bestie! this doc shipped with perl v5.40.1 on 2026-05-05, so that's when this little icon got her glow-up 🦋💅 mwah, go serialize something cute 💖