How to validate this data structure with Firebase security rules? - firebase

Question

So far not having any luck with Firebase Security rules.
I have this
{
"rules": {
"users": {
"$user_id": {
".read": true,
".write": "auth !== null && auth.uid === $user_id",
"profile": {
".validate": "newData.hasChildren(['first_name', 'last_name'])"
}
}
}
}
}
I send data and for the profile and one of them is blank... it lets it write any way. I wind up with data like so...
{
"users" : {
"simplelogin:25" : {
"profile" : {
"first_name" : "John",
"last_name" : ""
}
},
"simplelogin:26" : {
"profile" : {
"first_name" : "Bob",
"last_name" : ""
}
}
}
}
Any help on how to make the above rules work? Cant seem to get it to validate correctly.

Answer 1

Your validation rule is:
".validate": "newData.hasChildren(['first_name', 'last_name'])"
So the new data is valid if it has first_name and last_name properties.
You're sending this object over:
"profile" : {
"first_name" : "John",
"last_name" : ""
}
This object has a first_name and a last_name property, so it is valid according to your rule.
What you seem to want is that the properties don't only exist, but also are strings and have a minimum length. If that is indeed your requirement, you can write it into your validation rules:
"profile": {
".validate": "newData.hasChildren(['first_name', 'last_name'])",
"first_name": {
".validate": "newData.isString() && newData.val().length >= 10"
},
"last_name": {
".validate": "newData.isString() && newData.val().length >= 10"
}
}
The first .validate ensures that a profile has (at least) first_name and last_name properties. The other .validate rules ensure that they are of the correct type and minimum length.