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Mojolicious::Plugin::OpenAPI - OpenAPI / Swagger plugin for Mojolicious


  # It is recommended to use Mojolicious::Plugin::OpenAPI with a "full app".
  # See the links after this example for more information.
  use Mojolicious::Lite;

  # Because the route name "echo" matches the "x-mojo-name", this route
  # will be moved under "basePath", resulting in "POST /api/echo"
  post "/echo" => sub {

    # Validate input request or return an error document
    my $c = shift->openapi->valid_input or return;

    # Generate some data
    my $data = {body => $c->req->json};

    # Validate the output response and render it to the user agent
    # using a custom "openapi" handler.
    $c->render(openapi => $data);
  }, "echo";

  # Load specification and start web server
  plugin OpenAPI => {url => "data:///swagger.yaml"};

  @@ swagger.yaml
  swagger: "2.0"
  info: { version: "0.8", title: "Echo Service" }
  schemes: ["https"]
  basePath: "/api"
       x-mojo-name: "echo"
       - { in: "body", name: "body", schema: { type: "object" } }
           description: "Echo response"
           schema: { type: "object" }

See Mojolicious::Plugin::OpenAPI::Guides::OpenAPIv2 or Mojolicious::Plugin::OpenAPI::Guides::OpenAPIv3 for more in depth information about how to use Mojolicious::Plugin::OpenAPI with a "full app". Even with a "lite app" it can be very useful to read those guides.

Looking at the documentation for "x-mojo-to" in Mojolicious::Plugin::OpenAPI::Guides::OpenAPIv2 can be especially useful. (The logic is the same for OpenAPIv2 and OpenAPIv3)


Mojolicious::Plugin::OpenAPI is Mojolicious::Plugin that add routes and input/output validation to your Mojolicious application based on a OpenAPI (Swagger) specification. This plugin supports both version 2.0 and 3.x, though 3.x might have some missing features.

Have a look at the "SEE ALSO" for references to plugins and other useful documentation.

Please report in issues or open pull requests to enhance the 3.0 support.



  $hash = $c->openapi->spec($json_pointer)
  $hash = $c->openapi->spec("/info/title")
  $hash = $c->openapi->spec;

Returns the OpenAPI specification. A JSON Pointer can be used to extract a given section of the specification. The default value of $json_pointer will be relative to the current operation. Example:

    "paths": {
      "/pets": {
        "get": {
          // This datastructure is returned by default


  @errors = $c->openapi->validate;

Used to validate a request. @errors holds a list of JSON::Validator::Error objects or empty list on valid input.

Note that this helper is only for customization. You probably want "openapi.valid_input" in most cases.


  $c = $c->openapi->valid_input;

Returns the Mojolicious::Controller object if the input is valid or automatically render an error document if not and return false. See "SYNOPSIS" for example usage.


Mojolicious::Plugin::OpenAPI will emit the following hooks on the application object.


Emitted after all routes have been added by this plugin.

  $app->hook(openapi_routes_added => sub {
    my ($openapi, $routes) = @_;

    for my $route (@$routes) {

This hook is EXPERIMENTAL and subject for change.


This plugin register a new handler called openapi. The special thing about this handler is that it will validate the data before sending it back to the user agent. Examples:

  $c->render(json => {foo => 123});    # without validation
  $c->render(openapi => {foo => 123}); # with validation

This handler will also use "renderer" to format the output data. The code below shows the default "renderer" which generates JSON data:

    OpenAPI => {
      renderer => sub {
        my ($c, $data) = @_;
        return Mojo::JSON::encode_json($data);



  $route = $openapi->route;

The parent Mojolicious::Routes::Route object for all the OpenAPI endpoints.


  $jv = $openapi->validator;

Holds either a JSON::Validator::Schema::OpenAPIv2 or a JSON::Validator::Schema::OpenAPIv3 object.



  $openapi = $openapi->register($app, \%config);
  $openapi = $app->plugin(OpenAPI => \%config);

Loads the OpenAPI specification, validates it and add routes to $app. It will also set up "HELPERS" and adds a before_render hook for auto-rendering of error documents. The return value is the object instance, which allow you to access the "ATTRIBUTES" after you load the plugin.

%config can have:


See "coerce" in JSON::Validator for possible values that coerce can take.

Default: booleans,numbers,strings

The default value will include "defaults" in the future, once that is stable enough.


Instructions for "add_default_response_schema" in JSON::Validator::Schema::OpenAPIv2. (Also used for OpenAPIv3)


Set this to a default list of file extensions that your API accepts. This value can be overwritten by "x-mojo-to" in Mojolicious::Plugin::OpenAPI::Guides::OpenAPIv2.

This config parameter is EXPERIMENTAL and subject for change.


log_level is used when logging invalid request/response error messages.

Default: "warn".


op_spec_to_route can be provided if you want to add route definitions without using "x-mojo-to". Example:

  $app->plugin(OpenAPI => {op_spec_to_route => sub {
    my ($plugin, $op_spec, $route) = @_;

    # Here are two ways to customize where to dispatch the request
    $route->to(cb => sub { shift->render(openapi => ...) });
    $route->to(ucfirst "$op_spec->{operationId}#handle_request");

This feature is EXPERIMENTAL and might be altered and/or removed.


A list of OpenAPI classes to extend the functionality. Default is: Mojolicious::Plugin::OpenAPI::Cors, Mojolicious::Plugin::OpenAPI::SpecRenderer and Mojolicious::Plugin::OpenAPI::Security.

  $app->plugin(OpenAPI => {plugins => [qw(+Cors +SpecRenderer +Security)]});

You can load your own plugins by doing:

  $app->plugin(OpenAPI => {plugins => [qw(+SpecRenderer My::Cool::OpenAPI::Plugin)]});




route can be specified in case you want to have a protected API. Example:

  $app->plugin(OpenAPI => {
    route => $app->routes->under("/api")->to("user#auth"),
    url   => $app->home->rel_file("cool.api"),


Used to prevent calling "errors" in JSON::Validator::Schema::OpenAPIv2 for the specification.


Name of the route that handles the "basePath" part of the specification and serves the specification. Defaults to "x-mojo-name" in the specification at the top level.

spec, url

See "schema" in JSON::Validator for the different url formats that is accepted.

spec is an alias for "url", which might make more sense if your specification is written in perl, instead of JSON or YAML.

Here are some common uses:

  $app->plugin(OpenAPI => {url  => $app->home->rel_file('openapi.yaml'));
  $app->plugin(OpenAPI => {url  => ''});
  $app->plugin(OpenAPI => {spec => JSON::Validator::Schema::OpenAPIv3->new(...)});
  $app->plugin(OpenAPI => {spec => {swagger => "2.0", paths => {...}, ...}});


Can be used to overridden /info/version in the API specification, from the return value from the VERSION() method in version_from_class.

Defaults to the current $app. This can be disabled by setting the "version_from_class" to zero (0).


Project Founder

Jan Henning Thorsen -


  • Bernhard Graf <>

  • Doug Bell <>

  • Ed J <>

  • Henrik Andersen <>

  • Henrik Andersen <>

  • Ilya Rassadin <>

  • Jan Henning Thorsen <>

  • Jan Henning Thorsen <>

  • Ji-Hyeon Gim <>

  • Joel Berger <>

  • Krasimir Berov <>

  • Lars Thegler <>

  • Lee Johnson <>

  • Linn-Hege Kristensen <>

  • Manuel <>

  • Martin Renvoize <>

  • Mohammad S Anwar <>

  • Nick Morrott <>

  • Renee <>

  • Roy Storey <>

  • SebMourlhou <>

  • SebMourlhou <>

  • SebMourlhou <>

  • Søren Lund <>

  • Stephan Hradek <>

  • Stephan Hradek <>


Copyright (C) Jan Henning Thorsen

This program is free software, you can redistribute it and/or modify it under the terms of the Artistic License version 2.0.