如何使用用户输入为Firebase中的孩子命名？

Question

I'm trying to create a simple user database on Firebase for iOS. I have two textfields, one that takes the user's email address, and the other that takes the user's password. I want the email to be the user's uid. I try to accomplish this by creating a variable called "email" which I set equal to emailTextField.text! Then I implement the code that generates child(s) in Firebase, like so:

ref = Database.database().reference()

ref.child("users").child(email).setValue(true)

Here's my problem: creating a child and naming it using a variable, doesn't work. I can do the following just fine:

ref.child("users").child("email")

but once I take away the quotation marks around "email" so that it becomes the variable, the program crashes. How can I use user input to name a child in Firebase?

Answer 1

Firebase node / document names do not support the same character set which email addresses support, for example, the . symbol in an email address would make the child name invalid.

If you tried setting a child as ref.child("users").child("xyz@xyz.xyz") you should see the same error.

If you absolutely need to use the email address as the node name, I recommend encoding the email in a way which is compatible with the firebase node name rules.

Link to the rules

Edit: If you are using firebase auth, the normal pattern is too use the UID returned by the authenticated user object as the node name, not the email address entered from the textfield.

A quick example:

Auth.auth().signIn(withEmail: email, password: password) { (user, error) in
  if let user = user {
        ref.child("users").child(user.uid).setValue(true)
  }
}