get_addresses.py

import json
import csv
import requests
import os

"""
Simple tool to fetch the lat, lng coordinates of a list of addresses.

Requirements:

1. The tool requires "requests", a popular Python package, which can be
installed with "pip install requests".

2. This requires an API_KEY for the Google Maps Platform which can be obtained
by following the instructions here ...

https://developers.google.com/maps/documentation/geocoding/get-api-key

3. The tool requires an API_KEY for getaddresses.io, contact mark.turner@ncl.ac.uk for details

4. The tool requires a CSV file loaded with all the postcodes for the area of interest to be present in the same directory and named 'postcodes.csv'

"""

ADDRESS_API_KEY = "adresses.io-api-key"
GMAPS_API_KEY = "google-maps-geocoding-api-key"

addressURL = "https://api.getAddress.io/find/"
geocodeURL = "https://maps.googleapis.com/maps/api/geocode/json"

addresses = []

def get_addresses(postcode):
    """Return the addresses for a given postcode.

    Inputs:
        postcode (str): e.g. "NE1 7RU"

    Returns:
        address (list): e.g. ["Newcastle University, Newcastle upon Tyne, UK"]
    """
    print("Fetching addresses for " + postcode)

    r = requests.get(addressURL + postcode + "?api-key=" + ADDRESS_API_KEY)
    data = r.json()

    return data["addresses"]


def get_location(address):
    """Return the location of an address.

    Inputs:
        address (str): e.g. "Newcastle University, Newcastle upon Tyne, UK"

    Returns:
        location (tuple): (lat, lng)
    """

    params = {"key": GMAPS_API_KEY, "address": address}
    repsonse = requests.get(geocodeURL, params)
    results = repsonse.json()["results"]
    location = results[0]["geometry"]["location"]
    return (location["lat"], location["lng"])


def main():

    # open the postcodes file
    file = open(os.path.join("postcodes.csv"), "rU")
    reader = csv.reader(file, delimiter=",")

    # write addresses to file for backup
    with open('addresses.csv', 'w', newline='') as file:
        writer = csv.writer(file)
        writer.writerow(["Address,Postcode"])

        for row in reader:
            postcode = row[0]
            postcode_addresses = (get_addresses(postcode))

            # add addresses to global list
            addresses.extend(postcode_addresses)

            for address in postcode_addresses:
                writer.writerow([address,postcode])

    with open('locations.csv', 'w', newline='') as file:
        writer = csv.writer(file)
        writer.writerow(["Location"])

        # fetch a geolocation for every address
        for address in addresses:
            location = get_location(address)
            print(location)

            writer.writerow([location])

if __name__ == '__main__':
    main()