Heroku で Let's Encrypt 無料証明書を使う（自動更新あり） ref: http://qiita.com/blueplanet/items/b85634a0ced219e9ebe7

file0.txt

gem 'platform-api', github: 'jalada/platform-api', branch: 'master'
gem 'letsencrypt-rails-heroku', group: 'production'

file2.txt

$ heroku plugins:install heroku-cli-oauth
$ heroku authorizations:create -d "LetsEncrypt"
Created OAuth authorization.
  ID:          <heroku-client-id>
  Description: LetsEncrypt
  Scope:       global
  Token:       <heroku-token>

file3.txt

heroku config:add ACME_DOMAIN=example.com,www.example.com [email protected] HEROKU_APP=you_app_name HEROKU_TOKEN=上記で作成したtoken

file4.txt

heroku run rake letsencrypt:renew

file5.txt

# 毎月の1日が更新する
if [ "$(date +%d)" = 01 ]; then rake letsencrypt:renew; fi

file6.txt

# application_controller.rb　に追加
force_ssl if: :force_ssl?

private

  def force_ssl?
    not request.path =~ /^.well-known\/acme-challenge/
  end

file7.txt

# config/environments/production.rb
config.force_ssl = true
config.ssl_options = { redirect: { exclude: -> request { request.path =~ /^.well-known\/acme-challenge/ } } }

production.rb

Rails.application.configure do
  ...

  config.middleware.use Letsencrypt::Middleware

  ...
end