class PostsController
 def edit
    @post = PostForm.new(post.attributes, post.id)
  end

  def update
    @post = PostForm.new(params[:post], params[:id])

    if @post.save
      redirect_to @post
    else
      render :edit
    end
  end

  private

  def post
    Post.find(params[:id])
  end
end