Tools/tool_lib/geojson_map.py

import json
from typing import Optional

import cachetools


@cachetools.cached(cache=cachetools.LRUCache(maxsize=10000))
def latitude_of_zip_code_from_geojson(zip_code: str) -> Optional[float]:
    try:
        int(zip_code)
    except ValueError:
        return None
    for f in geojson_data['features']:
        if int(f['properties']['plz']) == int(zip_code):
            return f['geometry']['coordinates'][1]
    return None


@cachetools.cached(cache=cachetools.LRUCache(maxsize=10000))
def zip_code_exists(zip_code: str) -> bool:
    return latitude_of_zip_code_from_geojson(zip_code) is not None


@cachetools.cached(cache=cachetools.LRUCache(maxsize=10000))
def longitude_of_zip_code_from_geojson(zip_code: str) -> Optional[float]:
    try:
        int(zip_code)
    except ValueError:
        return None
    for f in geojson_data['features']:
        if int(f['properties']['plz']) == int(zip_code):
            return f['geometry']['coordinates'][0]
    return None


geojson_data = json.loads(open('resources/plz-5stellig-centroid.geojson').read())