Get list of users within individual geographical range

Question

A list of users with their location (long & lat) and a radius (in kilometers) is given in my firebase database, effectively defining individual "action circles", e.g.

{
  "users": {
    "foo": {
      "lat": 11.2549387,
      "long": 17.3419559,
      "radius": 50
    },
    "bar": {
      "lat": 9.5123445,
      "long": 17.1221547,
      "radius": 80
    }
  }
}

My goal is now to query all users whose circle covers a specific location (again long & lat). Since the list of users can be very long it makes no sense to simply calculate the distance to the location for every single user each time.

I am aware of GeoFire for JavaScript, but this does not solve my problem completely because it is not suitable for calculations with a non-fixed radius.

The solution should be either client-side (JavaScript) or as a cloud function. Any ideas on that?

Answer 1

Well GeoFire is the solution for you because it will optimize the query for you.

I am aware of GeoFire for JavaScript, but this does not solve my problem completely because it is not suitable for calculations with a non-fixed radius.

It will work with the non-fixed radius you just need to update your query's radius and/or lat long with the new user and it will get the nearby users.

For Geofire you need an extra seprate node to store each user's geolocation object