Firebase Realtime-Database Rule

{
  "rules": { // Root
    ".write": false, // everyone can't write
    ".read": false, // everyone can't read
    "live": { // rooms of live
        "rooms": { // root of rooms
          ".write": false, // everyone can't write
          ".read": false, // everyone can't read
          "$room": { // channels of rooms (but this is a variable of each room)
            	".write": false, // everyone can't write
              ".read" : "auth != null", // only authenticated users are can read
              "comments": {
                ".indexOn": ["date"], // We index basically the date
                "$commentid" : {
                  ".write": "!data.parent().parent().child('finish').exists() && !data.parent().parent().child('banned').child(auth.uid).exists() && data.parent().parent().exists() === true && !data.exists()",
              		".read": "auth != null",
                  // can send message
                  ".validate" : "newData.hasChildren(['comment','uid','did','date','username','slug','authid'])",
                  // rules of comments
                  "comment" : {
                    ".validate" : "newData.isString() && newData.val().length > 0 && newData.val().length < 500",
                  },
                  "uid" : {
                    ".validate" : "newData.val() === auth.uid"
                  },
                  "did": {
                    ".validate" : "newData.isNumber() && newData.val() > 0"
                  },
                  "date": {
                    ".validate" : "newData.isNumber() && newData.val() <= now",
                  },
                  "username": {
                    ".validate" : "newData.isString() && newData.val().length > 3"
                  },
                  "slug" : {
                    ".validate" : "newData.isString() && newData.val().length > 3"
                  },
                  "authid" : {
                    ".validate" : "newData.isNumber() && newData.val() > 0"
                  },
                  "$other" : {
                    ".validate" : false
                  }
                }
              }
          }
        }
    }
  }
}