database.rules.json

{
  "rules": {
    "rooms": {
      "$roomId": {
        ".read": true,
        ".write": "!data.exists() || data.child('owner').val() === auth.uid",
        "remotePlayers": {
          "$playerId": {
            ".read": true,
            ".write": "!data.exists() || $playerId === auth.uid"
          }
        }
      },
      ".indexOn": "updatedAt"
    },
    "roomsData": {
      "$roomId": {
        ".read": "auth.uid != null",
        ".write": "!data.exists() || data.child('owner').val() === auth.uid"
      },
      ".indexOn": "updatedAt"
    },
    "roomsRemotePlayers": {
      "$roomId": {
        ".read": "root.child('roomsData/'+$roomId+'/owner').val() === auth.uid",
        ".write": "!data.exists() || root.child('roomsData/'+$roomId+'/owner').val() === auth.uid",
        "$playerId": {
          ".read": "$playerId === auth.uid || root.child('roomsData/'+$roomId+'/owner').val() === auth.uid",
          ".write": "$playerId === auth.uid || root.child('roomsData/'+$roomId+'/owner').val() === auth.uid"
        }
      }
    },
    "roomsLocations": {
      "$roomId": {
        ".read": "auth.uid != null",
        ".write": "!data.exists() || root.child('roomsData/'+$roomId+'/owner').val() === auth.uid"
      }
    },
    "exports": {
      "$exportId": {
        ".read": "auth.uid != null",
        ".write": "!data.exists() || data.child('owner').val() === auth.uid",
      },
      ".indexOn": "createdAt"
    },
    "translations": {
      ".read": "auth.uid != null"
    }
  }
}