find all "coordinates" field in a geojson file, and output x,y coordinates as csv

geojson2csv.py

#!/usr/bin/python
# -*- coding: utf-8 -*-
# http://newtoypia.blogspot.tw/2015/08/admin-boundary.html
# 「臺灣各級行政區域(縣市/鄉鎮/村里)邊界座標檔， 自選解析度、 存成 csv、 畫成 svg 」

import json, argparse, sys, math, warnings

def ispoint(coords):
    return isinstance(coords, list) and isinstance(coords[0], (int, long, float)) and len(coords)==2

def coords2csv(coords):
    if ispoint(coords[0]):
        for p in coords:
            print '{0:f}{1:s}{2:f}'.format(p[0], args.delimiter, p[1])
        print
    else:
        map(coords2csv, coords)
        print

def geojson2csv(gjdata):
    if isinstance(gjdata, dict):
        if gjdata['type'] == 'FeatureCollection':
	    map(geojson2csv, gjdata['features'])
        elif gjdata['type'] == 'Feature':
            if 'geometry' in gjdata and isinstance(gjdata['geometry'],dict) and 'coordinates' in gjdata['geometry'] and isinstance(gjdata['geometry']['coordinates'],list) and len(gjdata['geometry']['coordinates'])>0:
               coords2csv(gjdata['geometry']['coordinates'])
        else:
            warnings.warn('ignoring "' + gjdata['type'] + '"')
        return gjdata
    elif isinstance(gjdata, list):
        return map(geojson2csv, gjdata)

parser = argparse.ArgumentParser(description='find all "coordinates" field in a geojson file, and output x,y coordinates as csv',formatter_class=argparse.ArgumentDefaultsHelpFormatter)
parser.add_argument('-d', '--delimiter', type=str,
    default=',', help='delimiter character between fields')
parser.add_argument('gjf', nargs='*', default='-', help='path to geojson files')
args = parser.parse_args()

for fn in args.gjf:
    gjfile = sys.stdin if fn == '-' else open(fn)
    gjdata = json.load(gjfile)
    geojson2csv(gjdata)
    # https://stackoverflow.com/questions/18337407/saving-utf-8-texts-in-json-dumps-as-utf8-not-as-u-escape-sequence
    if gjfile is not sys.stdin:
        gjfile.close()