How to Save User ID With Rails & JQuery Tokeninput? -

i following along this railscast jquery tokeninput , working. problem need figure out how save user id category upon creation. how can save within code?

model

class category < activerecord::base   belongs_to :user   has_and_belongs_to_many :entries    validates :name, :user_id, presence: true    def self.tokens(query)       categories = where("name ?", "%#{query}%")       if categories.empty?         [{id: "<<<#{query}>>>", name: "new: \"#{query}\""}]       else         categories       end     end      def self.ids_from_tokens(tokens)       tokens.gsub!(/<<<(.+?)>>>/) { create!(name: $1).id }       tokens.split(',')     end end 

controller

def index     @categories = category.order(:name)     respond_to |format|         format.html         format.json { render json: @categories.tokens(params[:q]) }     end   end 

as talked about, earlier. can use http://rails-bestpractices.com/posts/47-fetch-current-user-in-models access current_user inside of model.