How find nearest users by latitude and longitude?

Question

I\'m using firebase I\'m thinking the way how to do this.

1. get all user\'s latitude and logitude and save it to firebaseDB
2. sorting nearest users to me

Answer 1

You're on the right track. But there is no API to find the nearest user.

There is however an add-on library called GeoFire that allows you to find all keys within a certain range. It does this by encoding the user location in a so-called geohash, which it then allows you to query.

With this you could:

1. take a reasonable range
2. get all keys in that range through a geoquery
3. pick the closest key
4. if no key was found, expand the range