Validates Email Field From Controller

class User
VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i

if valid_email?(user.email)
user.save
redirect_to root_url, :notice => 'Good email'
else
flash[:error] = 'Bad email!'
render :new
end

private
def valid_email?(email)
email.present? &&
(email =~ VALID_EMAIL_REGEX) &&
User.find_by(email: email).empty?
end
end