descr_users_gold_ans.py

"""
CMSC 12300 / CAPP 30123
Task: Descriptive analysis (Exploring Users)

Main author: Sanittawan (Nikki) and Dhruval
"""
import csv

from geopy.exc import GeocoderTimedOut
from geopy.geocoders import Nominatim
from mrjob.job import MRJob


class FindLocUsersGoldBadges(MRJob):
    """
    A class for finding the location of users with 
    gold badge in answers, called illuminator.
    """
    def mapper(self, _, line):
        """
        Maps User ID to badges and  user id to user locations.
        Inputs:
            line: a single line in a CSV file
        Returns: 
            user id, badges or user id and location
            (depending on the file source)
        """
        row = csv.reader([line]).__next__()
        file = str(row[-1]).strip().lower()

        try:
            if file == "badges":
                badge_name = str(row[2]).strip().lower()
                badge_name = ''.join([char for char in \
                                      badge_name if char != "'"])
                user_id = str(row[1]).strip().lower()
                user_id = ''.join([char for char in user_id if char != "'"])

                if badge_name == "illuminator":
                    yield user_id, badge_name

            elif file == "users":
                user_id = str(row[0]).strip()
                location = str(row[6]).strip()

                if not location or user_id == "-1":
                    location = None
                    coord = None
                else:
                    try:
                        geolocator=Nominatim(timeout=3)
                        raw_location = geolocator.geocode(location)
                    
                        if raw_location:
                            coord = (raw_location.latitude,
                                     raw_location.longitude)
                            address = geolocator.reverse(
                                                    [raw_location.latitude,
                                                     raw_location.longitude],
                                                     language='en')
                            country = address.address.split()[-1]
                        else:
                            country = None
                            coord = None
                            
                    except GeocoderTimedOut as e:
                        msg = ("Error: geocode failed on input {}"
                               " with message {}".format(location,
                                                         e.message))
                        print(msg)

                    yield user_id, (coord, country)

        except (IndexError, ValueError):
            pass


    def reducer(self, user_id, vals):
        """
        Reduces to badges and location for a given userid
        Inputs:
            key: (string) User ID
            vals: (int) tuple of location and/or badge
        Returns: User ID as key and a list of location and badge as key
        """
        try:
            val_list = list(vals)
            if len(val_list) == 2:
                yield user_id, val_list
        except (TypeError, ValueError):
            pass


if __name__ == '__main__':
    FindLocUsersGoldBadges.run()