Method: Grape::Endpoint#present

Defined in:
lib/grape/endpoint.rb

#present(*args) ⇒ Object

Allows you to make use of Grape Entities by setting the response body to the serializable hash of the entity provided in the :with option. This has the added benefit of automatically passing along environment and version information to the serialization, making it very easy to do conditional exposures. See Entity docs for more info.

Examples:


get '/users/:id' do
  present User.find(params[:id]),
    with: API::Entities::User,
    admin: current_user.admin?
end



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# File 'lib/grape/endpoint.rb', line 318

def present(*args)
  options = args.count > 1 ? args.extract_options! : {}
  key, object = if args.count == 2 && args.first.is_a?(Symbol)
                  args
                else
                  [nil, args.first]
                end
  entity_class = options.delete(:with)

  # auto-detect the entity from the first object in the collection
  object_instance = object.respond_to?(:first) ? object.first : object

  object_instance.class.ancestors.each do |potential|
    entity_class ||= (settings[:representations] || {})[potential]
  end

  entity_class ||= object_instance.class.const_get(:Entity) if object_instance.class.const_defined?(:Entity)

  root = options.delete(:root)

  representation = if entity_class
                     embeds = { env: env }
                     embeds[:version] = env['api.version'] if env['api.version']
                     entity_class.represent(object, embeds.merge(options))
                   else
                     object
                   end

  representation = { root => representation } if root
  representation = (@body || {}).merge(key => representation) if key
  body representation
end