package models import "gopkg.in/mgo.v2/bson" const GALAXYSIZE = 50 const SOLARSYSTEMSIZE = 15 type SolarSystem struct { Id bson.ObjectId `json:"id", bson:"_id, omitempty"` Position int64 // position of the solar system in the galaxy, the maximum position is GALAXYSIZE-1 Planets []bson.ObjectId // array with ids of the planets, if empty is equal to "" }