Rails (newbie) - How to store a token variable in a link in db on create action -

i have problem create action , don't understand why wrong here.

users can follow link contain token variable. here route.

routes.rb

match "/:token" => "invitations#new", :via => :get 

on create action want token stored in sender_token instance in db.

i tried this:

invitation controller

  def new     @invitation = invitation.new   end    def create     @invitation = invitation.new(params[:invitation])     if @invitation.save        # here pb ???            @invitation.sender_token = :token        session[:invitation] = @invitation       mailer.invitation(@invitation).deliver       redirect_to invite_request_path     else       render :action => 'new'     end   end 

thank you!

shouldn't be

@invitation.sender_token = params[:token]