pflaenz.li/pflaenzli/pflaenzli/utils/distance.py

from geopy.distance import distance
import os
from pandas import read_pickle
from django.db.models import F, Func

path = os.path.dirname(os.path.abspath(__file__))

df = read_pickle(os.path.join(path, 'plz.pkl'))


def calculate_distance(zip_1, zip_2):
    if zip_1 == zip_2:
        return 0

    zip_1_coords = tuple(df[df.index == zip_1].values)
    zip_2_coords = tuple(df[df.index == zip_2].values)

    dist = round(distance((zip_1_coords), (zip_2_coords)).kilometers)

    return None if dist > 400 else dist


def filter_by_distance(qs, filter_zipcode, max_dist):
    filtered_offers = []
    for offer in qs:
        d = calculate_distance(int(offer.zipcode), int(filter_zipcode))
        if d is not None and d <= max_dist:
            filtered_offers.append(offer)
    return filtered_offers