Grape::ResourceDefinition

Based on Praxis principle, that design and implementation should be separated, I've created this gem to add the possibility to define the params validation & coercion outside the route's class.

If you are using Grape to create a Blog API (of course), you should have something like this:

class Posts < Grape::API

  desc 'Get all blog posts',
    http_codes: [
      [200, 'Ok']
    ]

  params do
    optional :q, type: Hash
    optional :order_by, type: String
    optional :order_dir, type: String
  end

  get '/posts' do
    # Logic to get those posts
  end

end

If your Posts API have only this route, to get all posts, it's ok. But if you have all actions to CRUD your posts, and some more to handle your specific business logic, this will become a mess... for sure.

This was a problem for me. I like my code to be as readable as possible and, with all these documentation and params definition that we need to create ou API, this is not possible.

So.. with this gem you can define your resource definition outside your route and call it when you need it.

module Resources

  module Posts

    include Grape::ResourceDefinition

    resource_define :index do

      desc 'Get all blog posts',
        http_codes: [
          [200, 'Ok']
        ]

      params do
        optional :q, type: Hash
        optional :order_by, type: String
        optional :order_dir, type: String
      end

    end

  end

end

...and your route links to that resource:

class Posts < Grape::API

  resource_definition Resources::Posts

  define :index
  get '/posts' do
    # Logic to get those posts
  end

end

I've made this really simple, the rest it's up to you. I don't want to add constraints on that.

Add this line to your application's Gemfile:

gem 'grape-resource-definition'

And then execute:

$ bundle

Or install it yourself as:

$ gem install grape-resource-definition