action-v1

  def index
    if !params[:year].blank? and !params[:month].blank? and !params[:day].blank?
      @date = Date.parse("#{params[:year]}-#{params[:month]}-#{params[:day]}")
    else
      @date = Date.today
    end
  end

action-v2

  def index
    begin
      @date = Date.parse("#{params[:year]}-#{params[:month]}-#{params[:day]}")
    rescue
      @date = Date.today
    end
  end