What are the pros and cons of using an email address as a user id?

Question

I\'m creating a web app that requires registration/authentication, and I\'m considering using an email address as the sole user id. Here are what I see as the pros and cons (upd

Answer 1

To solve your con item of the email being too long to type in every time. I have implemented the StringScan Ruby library.

require 'strscan'    
def signup!(user, &block)    
self.email = user[:email] unless user[:email].blank?    
str = StringScanner.new(self.email)    
str.scan_until(/@/)    
str.pre_match    
self.login = str.pre_match

etc..

Then just change login method to allow either email or login to match password.

This works just like google or mobileme. A user can choose to just type in their email username (ie. username instead of username@gmail.com.)