signup creating cognito user before sms verification

[acholyn]

We call the signUp() function on the sign up form and a cognito user is being created before they respond to the sms - noticed because we're currently unable to receive sms messages. In the lambda console we have a pre-signup thing, possibly it's something to do with this?

We probably need a new function that will just send a code without trying to init auth and then if they verify it we can sign them up and automatically authenticate them

[tcouch]

At the moment the pre-signup Lambda is automatically confirming the user and validating their number (I think that's just what whatever tutorial I was following did). I think really we want to add new users to the pool when they try to sign up, but not confirm them until they've passed the SMS challenge. If they try to sign up again later we should check if they're confirmed rather than if they exist.