Untitled

{
      "action" => "process_render_data",
      "book_id" => 14,
      "render_data" =>
        [
          {"page" => 1, "first_character" => 0, "last_character" => 99 },
          {"page" => 2, "first_character" => 100, "last_character" => 199 },
          {"page" => 3, "first_character" => 200, "last_character" => 299 },
          {"page" => 4, "first_character" => 300, "last_character" => 399 },
          {"page" => 5, "first_character" => 400, "last_character" => 499 }
        ]
    }