The gem creator kindly sends me an example of how to use GEM, try it, create a friendship controller that handles methods
class FriendshipsController < ApplicationController before_filter :authenticate_user! def index @friends = current_user.friends @pending_invited_by = current_user.pending_invited_by @pending_invited = current_user.pending_invited end def create @Friend = User.find(params[:user_id]) @friendship_created = current_user.invite(@Friend) if @friendship_created flash.now[:notice] = "Une demande d'amiti at envoye #{@friend.fullname}" end end def approve @Friend = User.find(params[:user_id]) @friendship_approved = current_user.approve(@Friend) @friends = current_user.friends @pending_invited_by = current_user.pending_invited_by flash.now[:notice] = "La demande d'amiti de #{@friend.fullname} at approuve" end def remove @Friend = User.find(params[:user_id]) @friendship = current_user.send(:find_any_friendship_with, @Friend) if @friendship @friendship.delete @removed = true flash.now[:notice] = "L'amiti avec #{@friend.fullname} at supprime" end end end