Check for oauth2 tokens.

It appears that Swagger-UI correctly sets an authorization header when
added in the interface (api key field). However, if the endpoint has
the option "authorizations" set with "oauth2", it will override the
value. See #13.

spec/dummy/app/api/api.rb

@@ -26,5 +26,10 @@ class API < Grape::API
     request.params.as_json
   end
 
+  desc 'Return oauth2 token', authorizations: { oauth2: [] }
+  get '/oauth2' do
+    request.headers.slice('Authorization').as_json
+  end
+
   add_swagger_documentation
 end

spec/features/swagger_spec.rb

@@ -89,6 +89,23 @@
         expect(page).to have_css 'span.string', text: 'dummy'
       end
     end
+    context '#api_auth:oauth2' do
+      before do
+        GrapeSwaggerRails.options.api_auth = 'bearer'
+        GrapeSwaggerRails.options.api_key_name = 'Authorization'
+        GrapeSwaggerRails.options.api_key_type = 'header'
+        visit '/swagger'
+      end
+      it 'adds a token when the route specifies oauth2 authorization' do
+        page.execute_script("$('#input_apiKey').val('token')")
+        page.execute_script("$('#input_apiKey').trigger('change')")
+        find('#endpointListTogger_oauth2', visible: true).click
+        first('a[href="#!/oauth2/GET_api_oauth2_format"]', visible: true).click
+        click_button 'Try it out!'
+        expect(page).to have_css 'span.attribute', text: 'Authorization'
+        expect(page).to have_css 'span.string', text: 'Bearer token'
+      end
+    end
     context '#before_filter' do
       before do
         GrapeSwaggerRails.options.before_filter do |_request|