class GdsApi::Base

def query_string(params)
  return "" if params.empty?
  param_pairs = params.sort.map { |key, value|
    case value
    when Array
      value.map { |v|
        "#{CGI.escape(key.to_s + '[]')}=#{CGI.escape(v.to_s)}"
      }
    else
      "#{CGI.escape(key.to_s)}=#{CGI.escape(value.to_s)}"
    end
  }.flatten
  "?#{param_pairs.join('&')}"
end