OC Transpo GPS API access in Ruby

gistfile1.rb

require 'open-uri'
require 'nokogiri'
require 'active_support/time'

module OCTranspo
  class GPSData

    API_URL = 'http://octranspo.opendataottawa.ca'
    API_KEY = 'YOUR API KEY HERE'

    def initialize(stop)
      @stop = stop
    end

    def trips(count = 3)
      url = "#{API_URL}/stop/#{@stop}/trips?count=#{count}&key=#{API_KEY}"
      doc = Nokogiri::XML(open(url))

      trips = {}

      doc.xpath('//xmlns:StopNextTripData', 'xmlns' => 'http://tempuri.org/').each do |trip|
        route = get_el(trip, 'ROUTE_NO').to_i
        direction = get_el(trip, 'DIRECTION')
        trips[route] ||= {}
        trips[route][direction[0,1]] ||= []

        trip_details = {
          :route       => route,
          :description => get_el(trip, 'ROUTE_DESCRIPTION').gsub(/\s?[\/\\-]+\s?/, '/'),
          :direction   => direction,
          :live        => get_el(trip, 'GPS_AVAILABLE') == 'true',
          :last_trip   => get_el(trip, 'LAST_TRIP') == 'true'
        }

        scheduled_seconds = get_el(trip, 'SCHEDULED_SECONDS').to_i
        trip_details[:scheduled_arrival] = seconds_to_time(scheduled_seconds)

        if trip_details[:live]
          trip_details.merge!({
            :latitude  => get_el(trip, 'LATITUDE').to_f,
            :longitude => get_el(trip, 'LONGITUDE').to_f,
            :estimated_arrival => seconds_to_time(scheduled_seconds + get_el(trip, 'ADHERENCE_SECONDS').to_i)
          })
        end

        trips[route][direction[0,1]] << trip_details
      end

      trips
    end

    def route_trips(route, count = 3)
      trips(count)[route.to_i]
    end

    def next_route_trip(route, direction = nil)
      trips = route_trips(route, 1)
      flattened_trips = direction ? trips[direction.upcase] : trips.to_a.flatten.select { |e| e.is_a?(Hash) }
      flattened_trips.sort { |a,b| (a[:estimated_arrival] || a[:scheduled_arrival]) <=>
                                   (b[:estimated_arrival] || b[:scheduled_arrival]) }.first
    end

    private

    def seconds_to_time(seconds)
      ActiveSupport::TimeZone['America/Toronto'].now.midnight + (seconds.to_i % 86400)
    end

    def get_el(node, el)
      node.at_xpath('xmlns:' + el, 'xmlns' => 'http://tempuri.org/').content
    end

  end
end