bart calculation

bart_calc.py

import requests
import urllib
from datetime import timedelta

from lxml.etree import fromstring

from dateutil.parser import parse
from dateutil.tz import tzlocal

from pandas import DataFrame
import numpy as np


try:
    # to allow import of a registered key if it exists
    from settings import BART_API_KEY
except:
    BART_API_KEY = "MW9S-E7SL-26DU-VV8V"

from pytz import timezone
pacific_tz = timezone("US/Pacific")


def etd(orig, key=BART_API_KEY):
    url = "http://api.bart.gov/api/etd.aspx?" +  \
            urllib.urlencode({'cmd':'etd',
                              'orig':orig,
                              'key':key})
                                                                  
    r = requests.get(url)
    doc = fromstring(r.content)
    
    estimations_list = []

    # parse the datetime for the API call

    s = doc.find('date').text + " " +doc.find('time').text
    call_dt = parse(s)
    
    # turn the results into a rectangular format

    # parse the station

    for station in doc.findall('station'):
        etds = station.findall('etd')
        for etd in etds:
            estimates = etd.findall('estimate')
            for estimate in estimates:
                estimate_tuple = [(child.tag, child.text) for child in estimate.iterchildren()]
                
                estimate_tuple += [('call_dt', call_dt),
                                   ('station', station.find('abbr').text),
                                   ('destination', etd.find('abbreviation').text)]
               
                estimations_list.append(dict(estimate_tuple))

    return estimations_list