Code snippet for queries to a Google REST API

gistfile1.py

for feature in data['features']:

	# Break after a couple of features for testing
# 	if feature['id'] == 2:
# 		break
	
	coords = feature['geometry']['coordinates']
	
	# Assemble locations for elevation query: 'lat,lng|lat,lng|etc'
	locStr = ''
	for latlng in coords:
		if locStr != '':
			locStr += '|'
		locStr += str(latlng[1]) + ',' + str(latlng[0])
			
	# Assemble elevation query
	url = baseUrl + '?locations=' + locStr + '&sensor=false'
	
	# The Elevation API prevents you from running queries too frequently,
	# so we have to catch failed queries and re-try them after a delay
	
	queryStatus = ''
	while queryStatus != 'OK':
	
		# Run elevation query
		response = json.load(urllib.urlopen(url))
		print 'query ' + str(queryCount + 1) + ': ' + response['status']
		
		if response['status'] == 'OK':
			queryStatus = 'OK'
			queryCount += 1
			time.sleep(0.1)
		
			# Add elevations to GeoJSON feature coordinates
			for i in range(0, len(coords)):
				elev = response['results'][i]['elevation']
				coords[i].append(elev)
	
		else:
			time.sleep(10)