Simple GeoIP service class using freegeoip.net and the Ruby Standard Library

geoip_service.rb

require 'net/http'
require 'ostruct'
require 'json'

class GeoipService
  def initialize(http = nil)
    @http = http || Net::HTTP.new('freegeoip.net')
  end

  def call(host)
    OpenStruct.new JSON.parse @http.get("/json/#{host}").body
  end
end

Albeit with no error checking.