Redis can be used to perform geo-spatial operations. Using geo-spatial indexing on objects, you can calculate radius, distance, and so on.

It takes a map of latitude and longitude stored against a key of location. Here's an example of the required schema of inserting geo locations into redis:

var redis = Spark.getRedis();
var geoLocation = {"Dublin": {"latitude":53.333099, "longitude":-6.248901}};
redis.geoadd("GEO_TEST_1", geoLocation);