A piece of code that will help paperclip to detect if the user is browsing your app in HTTPS and serve up S3 Images over the corresponding protocol.

paperclip_s3_url_rewriter.rb

#create this file in app/middleware and then in config/application.rb at the beginning of the application class you need to call it "config.middleware.use "PaperclipS3UrlRewriter"

class PaperclipS3UrlRewriter
  def initialize(app)
    @app = app
  end

  def call(env)
    status, headers, response = @app.call(env)
    if response.is_a?(ActionController::Response) && response.request.protocol == 'https://' && headers["Content-Type"].include?("text/html")
      body = response.body.gsub('http://s3.amazonaws.com', 'https://s3.amazonaws.com')
      headers["Content-Length"] = body.length.to_s
      [status, headers, body]
    else
      [status, headers, response]
    end
  end
end