Permission denied firebase.push()

Question

I'm using firebase with java. I used to add data by

firebaseRef.child("users").push().setValue(user);

where my user is object from User.class with the following attributes

String name;
String id;

When I added validation to the data to accept input that has id equals to a secret key id === 'secret id' as following

"user": {
    ".read": true,
    ".write": true,
    ".validate": "newData.hasChild('id')",
    "id": {
        ".validate": "newData.val() === 'secret id'"
    }
}

it shows me permission denied, I've tried many cases according to their documentation but I got the same permission denied.
Any suggestions?

Answer 1

Problem solved, Firebase.push() generates new id so newData doesn't refer to it anymore, I made a variable to represent that id so that I can access my data normally

"user": {
    "$key": {
        ".read": true,
        ".write": true,
        ".validate": "newData.hasChild('id')",
        "id": {
            ".validate": "newData.val() === 'secret id'"
        }
    }
}