Unable to create user PERMISSION_DENIED: Permission denied - firebase

Question

I am trying to create new user after I login with facebook/google, but getting error with:
error_handler.js:46 EXCEPTION: Uncaught (in promise): Error:
PERMISSION_DENIED: Permission deniedErrorHandler.handleError #
error_handler.js:46next # application_ref.js:291schedulerFn #
async.js:89SafeSubscriber.__tryOrUnsub #
PERMISSION_DENIED: Permission denied
my rules are:
"users": {
"$uid": {
// grants write access to the owner of this user account whose uid must exactly match the key ($uid)
".write": "auth !== null && auth.uid === $uid",
// grants read access to any user who is logged in with Facebook
".read": "auth !== null && (auth.provider === 'facebook' || auth.provider === 'google')"
}
}
when I remove my rules all works ok.
My code is:
private createNewUser(user: any): any {
const newUser = this.af.database.object('users/' + user.uid);
newUser.set({
username: user.name,
email: user.email,
profile_picture: user.avatar,
provider : user.provider,
create_date: new Date().toISOString().slice(0, 10).replace(/-/g, "")})
}
what fileds do i need to check?

Answer 1

You have mistake in your rules.
You allow write access only for existing users who already has uid under users/uid node but it you do not allow write access on users node.
You need to allow write access under users node. But this will cascade, which means that none of the .write rules under users node will be checked if .write rule under users node will evaluate to true. So you need to change your existing .write to .validate.
"users": {
// Grant every logged in user to write here
".write": "auth !== null",
"$uid": {
// .validate rule will restrict .write if current user id does not match the key ($uid)
".validate": "auth !== null && auth.uid === $uid",
// grants read access to any user who is logged in with Facebook
".read": "auth !== null && (auth.provider === 'facebook' || auth.provider === 'google')"
}
}
For more information about how to setup your security rules, read the following link and watch the video on this link.
https://firebase.google.com/docs/database/security/

Answer 2

Finally I use this rules for users.
"users": {
"$uid": {
// grants write access to the owner of this user account whose uid must exactly match the key ($uid)
".write": "!data.exists() || auth.uid === $uid",
// grants read access to any user who is logged in with Facebook
".read": "auth !== null && (auth.provider === 'facebook' || auth.provider === 'google')"
}
}