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Mojolicious::Plugin::JSONAPI - Mojolicious Plugin for building JSON API compliant applications


version 2.6


    # Mojolicious

    # Using route helpers

    sub startup {
        my ($self) = @_;

        $self->plugin('JSONAPI', {
            namespace => 'api',
            kebab_case_attrs => 1,

            resource => 'post',
            relationships => ['author', 'comments', 'email-templates'],

        # Now the following routes are available:

        # GET '/api/posts' -> to('api-posts#fetch_posts')
        # POST '/api/posts' -> to('api-posts#post_posts')
        # GET '/api/posts/:post_id -> to('api-posts#get_post')
        # PATCH '/api/posts/:post_id -> to('api-posts#patch_post')
        # DELETE '/api/posts/:post_id -> to('api-posts#delete_post')

        # GET '/api/posts/:post_id/relationships/author' -> to('api-posts#get_related_author')
        # POST '/api/posts/:post_id/relationships/author' -> to('api-posts#post_related_author')
        # PATCH '/api/posts/:post_id/relationships/author' -> to('api-posts#patch_related_author')
        # DELETE '/api/posts/:post_id/relationships/author' -> to('api-posts#delete_related_author')

        # GET '/api/posts/:post_id/relationships/comments' -> to('api-posts#get_related_comments')
        # POST '/api/posts/:post_id/relationships/comments' -> to('api-posts#post_related_comments')
        # PATCH '/api/posts/:post_id/relationships/comments' -> to('api-posts#patch_related_comments')
        # DELETE '/api/posts/:post_id/relationships/comments' -> to('api-posts#delete_related_comments')

        # GET '/api/posts/:post_id/relationships/email-templates' -> to('api-posts#get_related_email_templates')
        # POST '/api/posts/:post_id/relationships/email-templates' -> to('api-posts#post_related_email_templates')
        # PATCH '/api/posts/:post_id/relationships/email-templates' -> to('api-posts#patch_related_email_templates')
        # DELETE '/api/posts/:post_id/relationships/email-templates' -> to('api-posts#delete_related_email_templates')

        # If you're in development mode (e.g. MOJO_MODE eq 'development'), your $app->log will show the created routes. Useful!

        # You can use the following helpers too:

        $self->resource_document($dbic_row, $options);

        $self->compound_resource_document($dbic_row, $options);

        $self->resource_documents($dbic_resultset, $options);


This module intends to supply the user with helper methods that can be used to build a JSON API compliant API using Mojolicious. It helps create routes for your resources that conform with the specification, along with supplying helper methods to use when responding to requests.

See for the JSON API specification. At the time of writing, the version was 1.0.



The prefix that's added to all routes, defaults to 'api'. You can also provided an empty string as the namespace, meaning no prefix will be added.


This is passed to the constructor of JSONAPI::Document which will kebab case the attribute keys of each record (i.e. '_' to '-').


resource_routes(HashRef $spec)

Creates a set of routes for the given resource. $spec is a hash reference that can consist of the following:

        resource        => 'post', # name of resource, required
        controller      => 'api-posts', # name of controller, defaults to "api-{resource_plural}"
        relationships   => ['author', 'comments'], # default is []
        http_verbs      => ['get', 'post'], # default is ['get', 'post', 'patch', 'delete']
resource Str

The resources name. Should be a singular noun, which will be turned into it's pluralised version (e.g. "post" -> "posts") automatically where necessary.

controller Str

The controller name where the actions are to be stored. Defaults to api-{resource}, where resource is in its pluralised form.

Routes will point to controller actions, the names of which follow the pattern {http_method}_{resource}, with dashes replaced with underscores (i.e. 'email-templates' -> 'email_templates').

router Mojolicious::Routes

The parent route to use for the resource. Optional.

Provide your own router if you plan to use under for your resource.

NOTE: Providing your own router assumes that the router is under the same namespace already, so the resource routes won't specify the namespace themselves.


 my $under_api = $r->under('/api')->to('OAuth#is_authenticated');
     router => $under_api,
     resource => 'post',
relationships ArrayRef

The relationships belonging to the resource. Defaults to an empty array ref.

Specifying relationships will create additional routes that fall under the resource. These can then be used to reference self or related routes, as both will point to the same controller action i.e. /api/posts/1/relationships/author and /api/posts/1/author will go to Api::Posts::{http_method}_related_author. This is because in my opinion they're different routes with the same purpose, which is to action on the related resource.

NOTE: Your relationships should be in the correct form (singular/plural) based on the relationship in your schema management system. For example, if you have a resource called 'post' and it has many 'comments', make sure comments is passed in as a plural noun here.

http_verbs ArrayRef

The HTTP verbs/methods to use when creating the resources routes. Defaults to GET, POST, PATCH and DELETE, where GET is both for the collection route as well as the single resource route (e.g. /api/authors and /api/authors/:author_id).

Specifying this will not, if provided, affect the relationship routes that will be created. Those will have routes created for all verbs regardless.

render_error(Str $status, ArrayRef|Str $errors, HashRef $meta?)

Renders a JSON response under the required top-level errors key. errors should be an array reference of error objects as described in the specification, or a string that will be the content of title. See Error Objects.

Can optionally provide meta information, which will be added to the response as-is.


Convenience helper for controllers. Takes the query param include, used to indicate what relationships to include in the response, and splits it by ',' to return an ArrayRef.

 GET /api/posts?include=comments,author
 my $include = $c->requested_resources(); # ['comments', 'author']

Can also include nested relationships:

 GET /api/posts?include=comments,author.notes
 my $include = $c->requested_resources(); # ['comments', { author => ['notes'] }]

NOTE: Only one level of nesting is supported at the moment, so requests like author.notes.notes_relation won't give back what you expect. Stick with author.notes and lazy loading notes_relation.


Takes each query param fields[TYPE] and creates a HashRef containing all its requested fields along with any relationship fields. This is useful if you only want to return a subset of attributes for a resource.

The HashRef produced is suitable to pass directly to the options of JSONAPI::Document::resource_document.

Included fields should be direct attributes of the resource, not its relationships. See requested_resources for that use case.

The main resource should be in the plural form inside the param (i.e. 'posts', not 'post'), and related resources in their correct form.

 GET /api/posts?fields[posts]=slug,title&fields[comments]=likes&fields[author]=name,email

 my $fields = $c->requested_fields();

 # Out:
    fields => ['slug', 'title'],
    related_fields => {
        comments => ['likes'],
        author => ['name', 'email']


Available in controllers:

 $c->resource_document($dbix_row, $options);

See resource_document for usage.


Available in controllers:

 $c->compound_resource_document($dbix_row, $options);

See compound_resource_document for usage.


Available in controllers:

 $c->resource_documents($dbix_resultset, $options);

See resource_documents for usage.


  • Allow specifying http_verbs in the resource_routes helper for relationships.


This code is available under the Perl 5 License.