ctabus/ctabus.py

from urllib.parse import urlencode
from urllib.request import urlopen
from disk_cache import disk_cache
import json
from sensitive import api


def get_data(type, api_key=api, timeout=None, **args):
    base_url = "http://www.ctabustracker.com/bustime/api/v2/{type}?{query}"
    args['key'] = api_key
    args['format'] = 'json'
    url = base_url.format(type=type, query=urlencode(args))
    if timeout is not None:
        response = urlopen(url, timeout=timeout)
    else:
        response = urlopen(url)
    data = json.load(response)['bustime-response']
    try:
        data['error']
        raise Exception(str(data["error"]))
    except KeyError:
        return data


def get_times(stop_id, api_key=api, timeout=None):
    return get_data('getpredictions', api_key, stpid=stop_id, timeout=timeout)


@disk_cache
def get_routes(api_key=api, timeout=None):
    return get_data('getroutes', api_key, timeout=timeout)


@disk_cache
def get_directions(route, api_key=api, timeout=None):
    return get_data('getdirections', api_key, rt=route, timeout=timeout)


@disk_cache
def get_stops(route, direction, api_key=api, timeout=None):
    return get_data('getstops', api_key, rt=route, dir=direction,
                    timeout=timeout)


@disk_cache
def get_name_from_direction(route, direction, api_key=api, timeout=None):
    test_stop = get_stops(route, direction, api_key=api_key,
                          timeout=timeout)['stops'][0]['stpid']
    return get_times(test_stop, api_key=api, timeout=timeout)['prd'][0]['des']