disable cors

Gemfile

@@ -17,3 +17,4 @@ gem 'middleman-dotenv', '~> 2.0'
 gem 'middleman-data_source', '~> 0.8.1'
 gem 'middleman-livereload'
 gem 'html-proofer', '~> 3.7', '>= 3.7.2'
+gem 'rack-cors', '~> 1.0', '>= 1.0.2', :require => 'rack/cors'

Gemfile.lock

@@ -122,6 +122,7 @@ GEM
     parallel (1.11.2)
     public_suffix (2.0.5)
     rack (2.0.3)
+    rack-cors (1.0.2)
     rack-livereload (0.3.16)
       rack
     rack-test (0.6.3)
@@ -156,9 +157,10 @@ DEPENDENCIES
   middleman-livereload
   middleman-sprockets (~> 4.1.0)
   pandoc-ruby (~> 2.0)
+  rack-cors (~> 1.0, >= 1.0.2)
   tilt (~> 2.0)!
   tzinfo-data
   wdm (~> 0.1.0)
 
 BUNDLED WITH
-   1.15.2
+   1.16.4

config.ru

@@ -10,4 +10,14 @@ FileUtils.mkdir('log') unless File.exist?('log')
 
 app = ::Middleman::Application.new
 
+require 'rack/cors'
+use Rack::Cors do
+  allow do
+    origins '*'
+    resource '*',
+      headers: :any,
+      methods: [:get, :post, :put, :patch, :delete, :options, :head]
+  end
+end
+
 run ::Middleman::Rack.new(app).to_app