Ruby library for following out short urls to their end destination. LongUrl.new('http://t.co/fadsfs').longize

long_url

require 'net/http'
require 'uri'

class LongUrl
  
  attr_accessor :short_url
  attr_reader :long_url
  
  def initialize(short_url)
    @short_url = short_url
  end
  
  def longize
    begin
      response = fetch(short_url)
      if response.is_a?(Net::HTTPOK)
        self.long_url
      else
        raise NoLongUrlFound # This will never really happen since the fetch will error out first
      end
    rescue
      nil
    end
  end

  # This probably looks familiar if you've ever spent time with the Net::HTTP rdoc
  def fetch(uri_str, limit = 10)
    # You should choose better exception.
    raise ArgumentError, 'HTTP redirect too deep' if limit == 0

    response = Net::HTTP.get_response(URI.parse(uri_str))
    case response
    when Net::HTTPSuccess
      @long_url = uri_str
      response
    when Net::HTTPRedirection
      fetch(response['location'], limit - 1)
    else
      response.error!
    end
  end
  
end