Error RMagic en los carriles, con AM Gráficas

Question

Estoy usando amCharts y rieles. AmCharts utiliza el lib magia de imagen para exportar una imagen de la carta. En los carriles esto se hace con la gema, RMagic.

En un controlador de esto se implementa con el método siguiente controlador:

  def export
    width = params[:width].to_i
    height = params[:height].to_i
    data = {}
    img = Magick::Image.new(width, height)
    height.times do |y|
      row = params["r#{y}"].split(',')
      row.size.times do |r|
        pixel = row[r].to_s.split(':')
        pixel[0] = pixel[0].to_s.rjust(6, '0')
        if pixel.size == 2
          pixel[1].to_i.times do
            (data[y] ||= []) << pixel[0]
          end
        else
          (data[y] ||= []) << pixel[0]
        end
      end
      width.times do |x|
        img.pixel_color(x, y, "##{data[y][x]}")
      end
    end
    img.format = "PNG"
    send_data(img.to_blob , :disposition => 'inline', :type => 'image/png', :filename => "chart.png?#{rand(99999999).to_i}")
  end

Cuando se accede sin embargo el controlador, recibo este error en la página:

The change you wanted was rejected.

Maybe you tried to change something you didn't have access to.

Y esto error en los registros (que se ejecuta en su heroku por cierto):

    ActionController::InvalidAuthenticityToken (ActionController::InvalidAuthenticityToken):
  /home/heroku_rack/lib/static_assets.rb:9:in `call'
  /home/heroku_rack/lib/last_access.rb:25:in `call'
  /home/heroku_rack/lib/date_header.rb:14:in `call'
  thin (1.0.1) lib/thin/connection.rb:80:in `pre_process'
  thin (1.0.1) lib/thin/connection.rb:78:in `catch'
  thin (1.0.1) lib/thin/connection.rb:78:in `pre_process'
  thin (1.0.1) lib/thin/connection.rb:57:in `process'
  thin (1.0.1) lib/thin/connection.rb:42:in `receive_data'
  eventmachine (0.12.6) lib/eventmachine.rb:240:in `run_machine'
  eventmachine (0.12.6) lib/eventmachine.rb:240:in `run'
  thin (1.0.1) lib/thin/backends/base.rb:57:in `start'
  thin (1.0.1) lib/thin/server.rb:150:in `start'
  thin (1.0.1) lib/thin/controllers/controller.rb:80:in `start'
  thin (1.0.1) lib/thin/runner.rb:173:in `send'
  thin (1.0.1) lib/thin/runner.rb:173:in `run_command'
  thin (1.0.1) lib/thin/runner.rb:139:in `run!'
  thin (1.0.1) bin/thin:6
  /usr/local/bin/thin:20:in `load'
  /usr/local/bin/thin:20

Rendering /disk1/home/slugs/149903_609c236_eb4f/mnt/public/422.html (422 Unprocessable Entity)

Alguien tiene alguna idea de lo que está pasando aquí?

Answer 1

He lo descubrió:

añadido: require 'RMagick'

&

skip_before_filter: verify_authenticity_token

a mi clase