Support present with Grape::Presenters:Presenter

Author: u2

CHANGELOG.md

@@ -1,6 +1,10 @@
 0.12.0 (Next)
 =============
 
+#### Features
+
+* [#956](https://github.com/intridea/grape/issues/956): Support `present` with `Grape::Presenters::Presenter`  - [@u2](https://github.com/u2).
+
 #### Fixes
 
 * [#936](https://github.com/intridea/grape/pull/936): Fixed default params processing for optional groups - [@dm1try](https://github.com/dm1try).

README.md

@@ -1939,6 +1939,31 @@ Grape will automatically detect that there is a `Status::Entity` class and use t
 representative entity. This can still be overridden by using the `:with` option or an explicit
 `represents` call.
 
+You can present `hash` with `Grape::Presenters::Presenter` to keep things consistent.
+
+```ruby
+get '/users' do
+  present { id: 10, name: :dgz }, with: Grape::Presenters::Presenter
+end
+````
+The response will be
+
+```ruby
+{
+  id:   10,
+  name: 'dgz'
+}
+```
+
+It has the same result with
+
+```ruby
+get '/users' do
+  present :id, 10
+  present :name, :dgz
+end
+```
+
 ### Hypermedia and Roar
 
 You can use [Roar](https://github.com/apotonick/roar) to render HAL or Collection+JSON with the help of [grape-roar](https://github.com/dblock/grape-roar), which defines a custom JSON formatter and enables presenting entities with Grape's `present` keyword.

lib/grape.rb

@@ -127,6 +127,10 @@ module DSL
   class API
     autoload :Helpers,           'grape/api/helpers'
   end
+
+  module Presenters
+    autoload :Presenter,         'grape/presenters/presenter'
+  end
 end
 
 require 'grape/validations/validators/base'

lib/grape/presenters/presenter.rb

@@ -0,0 +1,9 @@
+module Grape
+  module Presenters
+    class Presenter
+      def self.represent(object, options = {})
+        object
+      end
+    end
+  end
+end

spec/grape/presenters/presenter_spec.rb

@@ -0,0 +1,70 @@
+require 'spec_helper'
+
+module Grape
+  module Presenters
+    module InsideRouteSpec
+      class Dummy
+        include Grape::DSL::InsideRoute
+
+        attr_reader :env, :request, :new_settings
+
+        def initialize
+          @env = {}
+          @header = {}
+          @new_settings = { namespace_inheritable: {}, namespace_stackable: {} }
+        end
+      end
+    end
+
+    describe Presenter do
+      describe 'represent' do
+        let(:object_mock) do
+          Object.new
+        end
+
+        it 'represent object' do
+          expect(Presenter.represent(object_mock)).to eq object_mock
+        end
+      end
+
+      subject { InsideRouteSpec::Dummy.new }
+
+      describe 'present' do
+        let(:hash_mock) do
+          { key: :value }
+        end
+
+        describe 'instance' do
+          before do
+            subject.present hash_mock, with: Grape::Presenters::Presenter
+          end
+          it 'presents dummy hash' do
+            expect(subject.body).to eq hash_mock
+          end
+        end
+
+        describe 'multiple presenter' do
+          let(:hash_mock1) do
+            { key1: :value1 }
+          end
+
+          let(:hash_mock2) do
+            { key2: :value2 }
+          end
+
+          describe 'instance' do
+            before do
+              subject.present hash_mock1, with: Grape::Presenters::Presenter
+              subject.present hash_mock2, with: Grape::Presenters::Presenter
+            end
+
+            it 'presents both dummy presenter' do
+              expect(subject.body[:key1]).to eq hash_mock1[:key1]
+              expect(subject.body[:key2]).to eq hash_mock2[:key2]
+            end
+          end
+        end
+      end
+    end
+  end
+end