myskill.py

# -*- coding: utf-8 -*-
import logging
import re
from six.moves.urllib.request import urlopen
import unirest
import json
from datetime import datetime
import arrow
import string


from flask import Flask
from flask_ask import Ask, request, session, question, statement

# Disclaimer: By no means can I claim this work is original. A
# very special thanks to John Wheeler (https://github.com/johnwheeler),
# creator of flask_ask. The following code is a mdoerately modified 
# example from his samples folder.

# Also, please note: you will need your own Mashape key for Transloc

# Finally, this is my first time using Python so I imagine there are more
# Python-y ways to solve some of the problems below. That's an exercise for
# the reader.

app = Flask(__name__)
ask = Ask(app, "/")
logging.getLogger('flask_ask').setLevel(logging.DEBUG)


# RTS Station Codes = Transloc Codes
# Displaying one for brevity
STATION_CODE_100 = "4090618"

# RTS Station Names = RTS Station Codes
# Displaying one for brevity
STATIONS = {}
STATIONS["Gtec"] = STATION_CODE_100

# Transloc Routes = RTS Route
# Displaying one for brevity
ROUTES = {}
ROUTES["4001150"] = "1"

# Constant defining number of events to be read at one time.
PAGINATION_SIZE = 1

# Length of the delimiter between individual events.
DELIMITER_SIZE = 2

# Size of events
SIZE_OF_EVENTS = 10

# Constant defining session attribute key for the event index
SESSION_INDEX = 'index'

# Constant defining session attribute key for the event text key for date of events.
SESSION_TEXT = 'text'

SESSION_STOP = "stop"

STOP_NAME = "stop"

ROUTE_NAME = None

@ask.launch
def launch():
    speech_output = "Bus Bus. What's your bus stop?"
    reprompt_text = "With Bus Bus you can find the next buses near your stop. " + \
                    "For example, you could say Bus Bus get the next 15 at Rosa Parks Downtown Station. " + \
                    "Or, you could say Bus Bus get the next bus at Butler Plaze. " + \
                    "Now, what's your bus stop?"
    return question(speech_output).reprompt(reprompt_text)
# Gets station and route from user
# Returns audio/visual output of one event
@ask.intent('GetFirstBusIntent')
def get_first_bus(Stations, Routes):

    # Declare global variables
    global STOP_NAME
    global ROUTE_NAME

    # Set variables
    ROUTE_NAME = Routes
    STOP_NAME = Stations

    # Need to get the routes from Transloc
    events = _get_json_events_from_transloc(STOP_NAME, ROUTE_NAME)

    # If no events, tell the user
    if not events:
        speech_output = "There are no buses that satisfy your query. Please try again later."
        return statement('<speak>{}</speak>'.format(speech_output))

    # If there are events return them
    else:
        card_title = ""
        speech_output = ""
        card_output = ""

        card_title = "RTS Bus "
        speech_output = "The "
        card_output = ""
        # Return the next bus (since PAGINATION_SIZE == 1)
        for i in range(PAGINATION_SIZE):
            speech_output += "{}".format(events[i][1]) + " arrives " + "{}".format(events[i][0]) + ". "
            card_output += "The next bus at " + STOP_NAME + " is the {}".format(events[i][1]) + ". It arrives in " + "{}".format(events[i][0]) + ". "
        # If no route was specified, just ask for next bus at stop
        if ROUTE_NAME == None:
            speech_output += "Would you like to know the next bus for " + STOP_NAME + "?"
        # If there was a bus route specified, ask for more of the same route at the stop
        else:
            speech_output += "Would you like to know the next " + ROUTE_NAME + " at " + STOP_NAME + "?"
            card_output += "Would you like to know the next bus?"
        reprompt_text = "Should I repeat that?"
        session.attributes[SESSION_INDEX] = PAGINATION_SIZE
        session.attributes[SESSION_TEXT] = events
        speech_output = '<speak>{}</speak>'.format(speech_output)
        return question(speech_output).reprompt(reprompt_text).simple_card(card_title, card_output)


# Gets: None
# Returns audio/visual output for the rest of the events
@ask.intent('GetNextBusIntent')
def get_next_bus():
    
    events = session.attributes[SESSION_TEXT]
    index = session.attributes[SESSION_INDEX]

    card_title = "RTS Buses"
    speech_output = ""
    card_output = ""

    i = 0
    # If there is only one bus, it would have been read in get_first_bus so there 
    # are no more buses to give to user. Alternatively, if the incremented index is
    # equal to the length of events that means there are no more buses to return. 
    # Therefore, we should alert the user and close the skill.
    if len(events) == 1 or i == len(events) or index == len(events):
        speech_output = "I'm sorry, but no more " + "{}".format(events[0][1]) + " arrive in the next hour. "
        card_output = "No more " + "{}".format(events[0][1]) + " arrive in the next hour. "
        return stop(speech_output)
    else:
        # If there are more buses to report then continue to inform the user of the remaining
        # buses available to the stop. Increment i for the check.
        while i < PAGINATION_SIZE and index < len(events):
            speech_output += "The " + "{}".format(events[index][1]) + " arrives " + "{}".format(events[index][0]) + ". "
            card_output += "The next bus is the " + "{}".format(events[index][1]) + ". It arrives " + "{}".format(events[index][0]) + ". "
            i += 1
            index += 1
            speech_output += "Would you like to know the next bus?"
    # Reprompt if necessary
    reprompt_text = "Did you want to know the next bus for " + STOP_NAME + "? "
    session.attributes[SESSION_INDEX] = index
    speech_output = '<speak>{}</speak>'.format(speech_output)
    return question(speech_output).reprompt(reprompt_text).simple_card(card_title, card_output)


@ask.intent('AMAZON.StopIntent')
def stop(text = ""):
    return statement(text + "Goodbye")



@ask.intent('AMAZON.CancelIntent')
def cancel():
    return statement("Goodbye")


@ask.session_ended
def session_ended():
    return "", 200

# Gets stop_name and route_name
# Returns mashape response and route_number
def _get_json_events_from_transloc(stop_name, route_name):

    # Set to None in case user did not specify
    route_number = None

    # Format Alexa speech to Capitalize The First Letter Of Each Word
    # This will match station name string format
    station = STATIONS.get(string.capwords(stop_name))

    # Find key in ROUTES based on value. In this case,
    # find route_number in ROUTES that's equal to ROUTE_NAME
    # Reminder, ROUTE_NAME is a global variable that holds the
    # user's route specification. Example, the 35 [bus].
    route = route_name
    for route in ROUTES:
        if ROUTES[route] == ROUTE_NAME:
            route_number = route

    # Call Mashape's hosted Transloc API
    # URL changes based on user's specified bus stops
    # returns json formatted data
    response = unirest.get("https://transloc-api-1-2.p.mashape.com/arrival-estimates.json?agencies=116&callback=call&stops=%s" % station,
  headers={
    "X-Mashape-Key": "your_mashape_key",
    "Accept": "application/json"
        }
    )

    # .body formats raw response
    unirest_response = response.body

    # If route is empty there are no routes available
    # Go back to get_first_bus to return an empty event
    # Else parse response
    if route == None:
        return None
    else:
        return _parse_json(unirest_response, route_number)


# Gets json response from mashape and bus route id
# Returns list of events containing arrival_times, bus_route_ids, and station_id
def _parse_json(unirest_response, route_id):

    # If data is empty there are no routes available
    # Go back to get_first_bus to return an empty event
    if unirest_response['data'] == []:
        return None
    else:
        number_of_arrivals = len(unirest_response['data'][0]['arrivals'])
        route_number = route_id

        # If route is None that means the user just wants all buses for that
        # route returned.
        if route_id == None:

            # If data is empty there are no routes available
            # Go back to get_first_bus to return an empty event
            if number_of_arrivals == 0:
                return

            # Else, for each arriving bus create an event with arrival time,
            # bus id, and station id
            events = [None]*number_of_arrivals
            i = 0
            while (i < number_of_arrivals):
                arrival_times = unirest_response['data'][0]['arrivals'][i]['arrival_at']
                bus_route_ids = unirest_response['data'][0]['arrivals'][i]['route_id']
                station_id = unirest_response['data'][0]['stop_id']
                events[i] = [arrival_times, bus_route_ids, station_id]
                i = i + 1

        # Since the user specified a route we need to parse through the
        # unirest_response and only grab data relevant to that route.
        # Then, for each arriving bus that is on the route specified,
        # create an event with arrival time, bus id, and station id
        else:
            number_of_arrivals = len(unirest_response['data'][0]['arrivals'])
            events = [None]*number_of_arrivals
            i = 0
            while i < number_of_arrivals:

                # The difference between this loop and the one above is the
                # check against route_number on the line below.
                if unirest_response['data'][0]['arrivals'][i]['route_id'] == route_number:
                    arrival_times = unirest_response['data'][0]['arrivals'][i]['arrival_at']
                    bus_route_ids = unirest_response['data'][0]['arrivals'][i]['route_id']
                    station_id = unirest_response['data'][0]['stop_id']
                    events[i] = [arrival_times, bus_route_ids, station_id]
                    i = i + 1

                # If a route returned in unirest_response does not match
                # the specified route then i is incremented. Empty events
                # are removed in _humanize: L = filter(None, var)
                else:
                    i = i + 1
    return _humanize(events)

# Gets list of events: arrival_times, bus_route_ids, station_id.
# Returns list of events: humanized_time, humanized_route.
def _humanize(events):

    # Empty events are filtered out
    filtered_events = filter(None, events)

    number_of_arrivals = len(filtered_events)
    humanized_events = [None]*number_of_arrivals
    humanized_time = [None]*number_of_arrivals
    i = 0
    while (i < number_of_arrivals):

        # Humanize time
        arrowObj = arrow.get(filtered_events[i][0])
        tmpDatetime = arrowObj.datetime
        local = arrowObj.to('US/Eastern')
        humanized_time = local.humanize()

        # Humanize route
        humanized_route = ROUTES.get(filtered_events[i][1])

        # Add humanized_time and humanized_route to humanized_events
        humanized_events[i] = [humanized_time, humanized_route]

        i = i + 1

    return humanized_events

if __name__ == '__main__':
    app.run(debug=True)