   defp save_image(base64_image, token) do
     normalized = base64_image |> String.split(",") |> List.last
     {:ok, image_data} = Base.decode64(normalized)
-    host = Application.get_env(:beer_napkin, :s3_host)
-    bucket = Application.get_env(:beer_napkin, :s3_bucket)
     BeerNapkin.S3.save_png("#{token}.png", image_data)
   end
 
-  defp update_image(napkin, base64_image, key) do
+  defp update_image(napkin, base64_image) do
     normalized = base64_image |> String.split(",") |> List.last
     {:ok, image_data} = Base.decode64(normalized)
     BeerNapkin.S3.update_png(napkin.image_key, image_data)

  use BeerNapkin.Web, :controller
  plug :authenticate
  alias BeerNapkin.Napkin
  @s3_host Application.get_env(:beer_napkin, :s3_host)
  @s3_bucket Application.get_env(:beer_napkin, :s3_bucket)

  def new(conn, _params) do
    changeset = Napkin.changeset(%Napkin{})

  def update(conn, %{"id" => id, "napkin" => napkin_params, "napkin_image" => image}) do
    case load_napkin(conn, id) do
      {:ok, napkin} ->
        update_image(napkin, image)
        update_params = Map.take(napkin_params, [
          "json", "repository_full_name", "issue_title", "issue_description"
        ])
