ruby-on-rails - :only work in this ruby code?如何

Question

今天刚开始学ruby，对下面的代码有疑问。我想知道“:only =>:show”到底是如何影响这里的代码的。我假设如果我们没有“:only =>:show”，那么代码将直接处理身份验证。但是“:only =>:show”到底是做什么的呢？谢谢!

class PeopleController < ApplicationController

  before_filter :authenticate, :only =>:show

  def index
    @people = ["luke-skywalker", "darth-vader"]
  end

  def show
    @person = params[:id]
  end

  private

  def authenticate
    if params[:id] == "darth-vader"
      redirect_to people_url, :notice => "The page is restricted."
      #this is called the flash message
    end
  end
end

Answer 1

过滤器之前是一个回调，表示在处理您调用的实际操作之前调用此方法。 :only => :show 告诉回调只为 show Action 做那件事。如果取出来，则在所有 Action 之前调用该方法