Rails 4, devise, omniauth, facebook: problems when regular sign up involves nested forms - facebook

Question

I am trying to set up facebook login integration with omniauth and devise.
Note that I have a MEMBER model which contains the devise info and a USER model that contains the member profile info (to keep them separate)
On the sign up page, the user has a nested form in the member sign up form and receives all the user data at that time. Once the member is saved, the email value for the saved member is also entered into the user table like so
class Member < ActiveRecord::Base
# Include default devise modules. Others available are:
# :confirmable, :lockable, :timeoutable and :omniauthable
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable, :confirmable, :omniauthable
after_save :update_user
def update_user
user.email = self.email
user.save
end
I have the standard model method for the facebook data processing.....
def self.process_omniauth(auth)
where(provider: auth.provider, uid: auth.uid, email: auth.info.email).first_or_create do |member|
member.provider = auth.provider
member.uid = auth.uid
member.email = auth.info.email
end
end
But of course, in this case, there is no nested form so the 'user' is not instantiated and it throws an error when the update_user method is called on saving the member.
How can I modify this method above to instantiate a new user, when signing up via the facebook pathway?
EDIT: This works.....
def update_user
if User.find_by_member_id(self.id).present?
user.email = self.email
user.save
else
User.create(:email => self.email, :member_id => self.id)
end
end
BUT THIS RESULTS IN A CONSTRAINT ERROR - on email - it already exists in the database. From the logs, the else statement here appears to be attempting to create the user twice.
def update_user
if User.find_by_member_id(self.id).present?
user.email = self.email
user.save
else
User.create(:email => self.email)
end
end
Can anyone explain this? I am suprised I had to pass the foreign key to the user in the else block.

Answer 1

I'm not sure what fields are being stored in the User Model but what you should be doing here that in case of Facebook Callback you should create the User if the Member don't have an user associated with it. i.e your update_user should be something like this:
def update_user
if user.present?
user.email = self.email
user.save
else
User.create(:email => self.email, :member_id => self.id)
/*note that a lot of other information is returned in
facebook callback like First Name, Last Name, Image and
lot more, which i guess you should also start saving to
User Model */
end
end
**** EDIT ******** . You should also check if there is user with the same email and associate that with the member.
def update_user
if user.present?
user.email = self.email
user.save
else
user = User.find_by_email(self.email)
if user
user.update_attribute(:member_id, self.id)
else
User.create(:email => self.email, :member_id => self.id)
end
end