Multiple providers, one solution, generate password randomly.

devise.rb

  def self.from_omniauth(auth)
    unless provider = Provider.where(auth.slice(:provider, :uid)).first # New User
      provider = Provider.new(provider: auth.provider, uid: auth.uid, oauth_token: auth.credentials.token)
      user = User.where(email: auth.info.email).first # If user is already a devise user
      if user.nil? # New user
        random_password = (0...8).map{(65+rand(26)).chr}.join
        user = User.create(email: auth.info.email, password: random_password, password_confirmation: random_password, confirmed_at: Time.now)
      end
      provider.user = user
    end
    provider.save
    provider
      #provider.user.save!
      #provider.user.name = auth.info.name
      #provider.user.avatar = auth.info.image.gsub("type=square", "width=160&height=160")
    # end
  end

  def password_required?
    return true if reset_password_token.present? && reset_password_period_valid?

    unless encrypted_password.blank?
      password.present? || password_confirmation.present?
    end
  end