I want to prevent duplicate username while signUp form what user entered. I have created email login like below, firtly createUser and then auth it setValue with user dictionary.
But I stack with Firebase security settings and how to check handle this situation.
REF_BASE.createUser(email, password: pwd, withValueCompletionBlock: { ..
REF_BASE.authUser(email, password: pwd, withCompletionBlock: { ..
REF_USERS.childByAppendingPath(uid).setValue(user)
This handling always response error.
REF_USERS.childByAppendingPath(uid).childByAppendingPath("username").setValue(user["username"]) { (error: NSError!, result: Firebase!) in
if error != nil {
print(error.localizedDescription)
}
else {
self.REF_USERS.childByAppendingPath(uid).setValue(user)
}
}
This is my security rules, How Can I fix everything to be prevented from duplicate user?
"users": {
".read": "auth !== null",
"$user": {
"username": {
".read": "auth !== null",
".write": "newData.val() === auth.uid && !data.exists()"
}
}
},
Update:
From Frank's answer, but I don't know what I need to do while signUp new user for swift in this situation.
app : {
users: {
"some-user-uid": {
email: "test@test.com"
username: "myname"
}
},
usernames: {
"myname": "some-user-uid"
}
}
Need I add same user uid at the same time for two different nodes? If someone explain it in Swift. It would be great.
"users": {
"$uid": {
".write": "auth !== null && auth.uid === $uid",
".read": "auth !== null && auth.provider === 'password'",
"username": {
".validate": "
!root.child('usernames').child(newData.val()).exists() ||
root.child('usernames').child(newData.val()).val() == $uid"
}
}
}
I couldn't add new user informations to usernames parent node. It's needed another security rules?
If you are trying to prevent duplicate Firebase usernames, that can be done right at the createUser stage.
Assume a dialog is presented to new user asking to create an account: this will get their desired userName and password.
Send that to createUser and if there's an error (because it already exists) notify them and ask for a different userName:
myRootRef.createUser(email, password: pw, withValueCompletionBlock: { error, result in
if error != nil {
self.errMsgField.stringValue = "email/username in use, try again"
} else {
let uid = result["uid"] as! String //the uid of the new user
print("user created as \(uid)")
self.authUserWithAuthData( email, password: pw ) //auth the user
}
})
After the user is created you would probably add their info the /users node as well.
来源：https://stackoverflow.com/questions/36915473/how-prevent-username-from-duplicate-signup-in-firebase