How to provide user login with a username and NOT an email?
I'd like to use Firebase for my web app that is for people with dementia in a care home. They do not have email or social network accounts so will need a simple username / password sign up / sign in.
What is the easiest way to do this? From what I can see in the docs I'd have to use a custom auth flow but I do not have an existing auth server.
If I do need ot do this what is the easiest way to provide the token? In Azure there is Functions and AWS has Lambda but I see nothing here is Firebase
Answer
You are correct that username/password sign-in is not supported natively in Firebase Auth at this moment.
You can implement a custom provider as shown in this example. This allows you to meet any custom requirements, but is admittedly a bit more involved than using the built-in providers. There is an example of this here that you can use as a starting point.
A workaround you could take without needing to use custom auth with another backend is to accept usernames in your UI, but on the underlying logic, append "@yourowndomain.com" before calling the functions to sign up or sign in with email.
So you would be using email/password authentication, mapping <username> to <username>@yourowndomain.com