Python app to allow a user plan their journey from start to destination using Transport For London Live Service

tfltravelguide.py

#!/usr/bin/env python3
import requests
import re
import json
import sys
import time

##### IF YOU ARE USING COMMAND LINE TO RUN THIS PLS DO  pip install  requests  re  json  sys  time
# get current postcode from user     -> DONE
# get destination postcode from user -> DONE
# check it meets the required format -> DONE
# complete the url with placeholders -> DONE
# submit request                     -> DONE
# process response check for errors  -> DONE
# process response to display data   -> DONE

tfl_provided_app_id = "99acf05e"
tfl_provided_app_key = "a5d066ef8faf90351c9cc1ff438648e3"
CONSTANT_REGULAR_EXPRESSION_FOR_POSTCODE = "([Gg][Ii][Rr] 0[Aa]{2})|((([A-Za-z][0-9]{1,2})|(([A-Za-z][A-Ha-hJ-Yj-y][0-9]{1,2})|(([A-Za-z][0-9][A-Za-z])|([A-Za-z][A-Ha-hJ-Yj-y][0-9][A-Za-z]?))))\s?[0-9][A-Za-z]{2})"
CONSTANT_BASE_URL_FOR_TRANSPORT_FOR_LONDON = "https://api.tfl.gov.uk/journey/journeyresults/{}/to/{}?app_id={}&app_key={}"
CONSTANT_JOURNEYS = "journeys"
CONSTANT_DURATION = "duration"
CONSTANT_LEGS = "legs"
CONSTANT_NUMBER_OF_MINUTES_IN_AN_HR = 60
CONSTANT_FARE = "fare"
CONSTANT_TOTAL_COST = "totalCost"
CONSTANT_FARES = "fares"
CONSTANT_INSTRUCTION = "instruction"
CONSTANT_DETAILED = "detailed"
CONSTANT_MODE = "mode"
CONSTANT_NAME = "name"
input_user_start_postcode = ""
input_user_end_postcode = ""


def getTravelInstructionsFromUser():
    input_user_start_postcode = input("\nPlease enter the postcode of where you are starting your journey: ")
    input_user_end_postcode = input("\nPlease enter the postcode of where you are going: ")
    return [input_user_start_postcode, input_user_end_postcode]


def validateUserEnteredInstructions(travel_instructions):
    print(travel_instructions[0])
    print(travel_instructions[1])
    return re.search(CONSTANT_REGULAR_EXPRESSION_FOR_POSTCODE, travel_instructions[0]) and re.search(
        CONSTANT_REGULAR_EXPRESSION_FOR_POSTCODE,
        travel_instructions[1])


def completeTheUrlForTheRequestToTheServer(travel_instructions):
    return CONSTANT_BASE_URL_FOR_TRANSPORT_FOR_LONDON.format(travel_instructions[0], travel_instructions[1],
                                                             tfl_provided_app_id, tfl_provided_app_key).replace(" ", "")


def getTimeInMinutesAndSections(data, journeyIndex):
    journeys = data[CONSTANT_JOURNEYS]
    print(journeys[journeyIndex][CONSTANT_DURATION])


def getAverageTravelTime(data):
    journeys = data[CONSTANT_JOURNEYS]
    totalTime = 0
    for journeyIndex in range(len(journeys)):
        totalTime += journeys[journeyIndex][CONSTANT_DURATION]
    averageTravelTime = abs(totalTime / len(journeys))
    return (len(journeys), int(averageTravelTime / CONSTANT_NUMBER_OF_MINUTES_IN_AN_HR),
            int(averageTravelTime % CONSTANT_NUMBER_OF_MINUTES_IN_AN_HR))


def displayTheTravelOptionsToTheUser(data):
    computedAverageTimeTuple = getAverageTravelTime(data)
    computedAverageArrivalTime = computeEstimatedArrivalTimeBasedOnAverageTime(computedAverageTimeTuple)
    print(
        "There are {} routes  and  {}  TFL lines available to you when embarking on this journey and Average Travel Time across all {} routes is: {} hours and {} minutes."
        "\nThe time now is {}:{} and your estimated arrival time is {}:{}".
            format(len(data["journeys"]), len(data["lines"]), computedAverageTimeTuple[0],
                   computedAverageTimeTuple[1], computedAverageTimeTuple[2], computedAverageArrivalTime[0],
                   computedAverageArrivalTime[1], computedAverageArrivalTime[2], computedAverageArrivalTime[3]))


def retrieveJourneyWithShortestTravelDuration(data):
    journeys = data[CONSTANT_JOURNEYS]
    listOfDurations = {}
    for journeyIndex in range(len(journeys)):
        listOfDurations[journeyIndex] = [journeys[journeyIndex][CONSTANT_DURATION]]
    return journeys[sorted(listOfDurations)[0]]


# to display a journey I need the index of the journey or just the journey data


# to display a journey I need the index of the journey or just the journey data
def displaySpecificJourneyDetails(data, journeyIndex=None):
    """ if we pass index then get the journey by that index else use data as it is"""
    singleJourneyWeAreInterestedIn = data
    if journeyIndex != None:
        journeys = data[CONSTANT_JOURNEYS]
        singleJourneyWeAreInterestedIn = journeys[journeyIndex]
        legsOfThisJourney = singleJourneyWeAreInterestedIn[CONSTANT_LEGS]
    else:
        legsOfThisJourney = data[CONSTANT_LEGS]

    if singleJourneyWeAreInterestedIn.get(CONSTANT_FARE):
        journeyFareInformation = "Travel Cost: £{}".format('{:,.2f}').format(
            singleJourneyWeAreInterestedIn[CONSTANT_FARE][CONSTANT_TOTAL_COST] / 100)
    else:
        journeyFareInformation = "No Cost Information"
    print("\n++++++++++++++++++++++++JOURNEY START++++++++++++++++++++++++++++++++++++++\n")
    print("\nJourney Duration(Approx): {} --> {} \n".format(singleJourneyWeAreInterestedIn[CONSTANT_DURATION],
                                                            journeyFareInformation))
    displayTheDetailedStepsForThisJourney(legsOfThisJourney)
    print("\n++++++++++++++++++++++++JOURNEY END++++++++++++++++++++++++++++++++++++++\n")


def displayTheDetailedStepsForThisJourney(data):
    for indexOfThisJourney in range(len(data)):
        singleJourneyLeg = data[indexOfThisJourney]
        informationToDisplay = "Duration: {} mins {} {} {} {}{}" \
            .format(int(singleJourneyLeg[CONSTANT_DURATION]), "**** ",
                    singleJourneyLeg[CONSTANT_INSTRUCTION][
                        CONSTANT_DETAILED], "**** ",
                    (lambda string: string.upper())(singleJourneyLeg[CONSTANT_MODE][
                                                        CONSTANT_NAME])
                    , " **** ")
        print("\n{}".format(informationToDisplay))


def displayEverthingJor(data):
    print("\n\n")
    journeys = data[CONSTANT_JOURNEYS]
    for index in range(len(journeys)):
        print(displaySpecificJourneyDetails(data, index))


def computeEstimatedArrivalTimeBasedOnAverageTime(computedAverageTimeTuple):
    localtime = time.localtime(time.time())
    hours = localtime.tm_hour
    mins = localtime.tm_min

    if (hours < 10):
        formattedHours = "0{}".format(hours)
    else:
        formattedHours = "{}".format(hours)

    if (mins < 10):
        formattedMins = "0{}".format(mins)
    else:
        formattedMins = "{}".format(mins)

    expectedArrivalTimeInHours = int(formattedHours) + computedAverageTimeTuple[1]
    expectedArrivalTimeInMins = int(formattedMins) + computedAverageTimeTuple[2]

    if (expectedArrivalTimeInMins > CONSTANT_NUMBER_OF_MINUTES_IN_AN_HR):
        expectedArrivalTimeInHours += expectedArrivalTimeInMins / CONSTANT_NUMBER_OF_MINUTES_IN_AN_HR
        expectedArrivalTimeInMins = expectedArrivalTimeInMins % CONSTANT_NUMBER_OF_MINUTES_IN_AN_HR

    return (formattedHours, formattedMins, int(expectedArrivalTimeInHours), int(expectedArrivalTimeInMins))


def submitRequestToTFL(completeUrlForTFL):
    try:
        r = requests.get(completeUrlForTFL, 10)
        data = json.loads(r.content.decode())
        return data

    except requests.exceptions.Timeout as requestTimedOutOrTookTooLong:
        print(requestTimedOutOrTookTooLong)
        sys.exit(1)

    # Maybe set up for a retry, or continue in a retry loop
    except requests.exceptions.TooManyRedirects as tooManyReDirects:
        print(tooManyReDirects)
        sys.exit(1)

    # Omo! URL was bad  try a different one
    except requests.exceptions.RequestException as thatUrlYouSentWasDodgy:
        print(thatUrlYouSentWasDodgy)
        sys.exit(1)


if __name__ == '__main__':

    while True:
        user_input = []
        user_input = getTravelInstructionsFromUser()
        isUserEnteredDataInTheRightFormat = validateUserEnteredInstructions(user_input)
        if isUserEnteredDataInTheRightFormat != None:
            print("Ok! Retrieving a route for you..Please wait a few seconds!")
            completeUrlForTFL = completeTheUrlForTheRequestToTheServer(user_input)
            print(completeUrlForTFL)
            data = submitRequestToTFL(completeUrlForTFL)

            if (data != None and data.get(CONSTANT_JOURNEYS) != None):
                displayTheTravelOptionsToTheUser(data)
                # display quickest journey yes or no
                # input == yes       # print(displaySpecificJourneyDetails(retrieveJourneyWithShortestTravelDuration(data)))
                # input == no displayEverythingJor
                howToDisplayTheJourneyInformationRetrieved = input(
                    "\nDo you wish to see the quickest journey to your destiznation? 'Y' or 'N': ").lower()
                if howToDisplayTheJourneyInformationRetrieved == "y":
                    displaySpecificJourneyDetails(retrieveJourneyWithShortestTravelDuration(data))
                else:
                    displayEverthingJor(data)

            else:
                print("Sorry Couldn't find a viable route for you")
        else:
            print("Sorry there was a problem with the postcodes you entered!...Try again")

        continueResponse = input("Do you wish to try finding a new journey? 'Y' or 'N'     ").lower()
        if (continueResponse == "y"):
            continue
        else:
            sys.exit(0)