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Python class for TriMet train arrivals

I wanted a Bash alias that would output the time remaining until the next Eastbound train at the stop near my apartment. I created a Python class to get this data that I could implement in a script. This class takes as parameters your TriMet API key and the ID of the stop. To obtain a TriMet API key, visit http://developer.trimet.org/.

The data that the API returns is documented here: http://developer.trimet.org/ws_docs/.

#!/usr/bin/python

import urllib2 import json import datetime import math

class NextTrain:

def __init__(self, stopID, apiKey):
  self.__stopID = stopID
  self.__apiKey = apiKey


def printNextArrival(self):
  base_url = "http://developer.trimet.org/ws/V1/arrivals?"


  response = urllib2.urlopen(base_url + "locIDs=" + str(self.__stopID) + "&appID=" + self.__apiKey + "&json=true")
  data = response.read()
  jsonData = json.loads(data)


  direction = jsonData["resultSet"]["location"][0]["dir"]
  firstResult = jsonData["resultSet"]["arrival"][0]
  station = jsonData["resultSet"]["location"][0]["desc"]
  trainType = firstResult["shortSign"]
  nextArrivalTime = datetime.datetime.strptime(firstResult["estimated"], "%Y-%m-%dT%H:%M:%S.000-0800")
  nowTime = datetime.datetime.now()
  timeRemaining = nextArrivalTime - nowTime
  print "Next " + direction + " train at " + station + ":"
  print str(int(math.floor(timeRemaining.total_seconds() / 60))) + " min"
  print trainType
  response.close()

Using this class:

apiKey = “yourAPIKey” stopID = integer_stop_id_here nextTrain = NextTrain(stopID, apiKey) nextTrain.printNextArrival()

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