1 在编写filter的时候，注意filter的顺序，不然里面的属性会被其他的filter覆盖，比如控制路由跳转会被PreDecorationFilter覆盖
2 具体的内容可以阅读源码。
3 


经过测试，所有访问这个路由地址的请求，只有在application.yml中已经匹配到了路径的，才会触发拦截器。7也就是说，在我们定制的和已知的拦截器之前，
就已经有一个过滤请求性质的东西了。


Zuul RequestContext
To pass information between filters, Zuul uses a RequestContext. Its data is held in a ThreadLocal specific to each request. 
Information about where to route requests, errors, and the actual HttpServletRequest and HttpServletResponse are stored there. 
The RequestContext extends ConcurrentHashMap, so anything can be stored in the context. 
FilterConstants contains the keys used by the filters installed by Spring Cloud Netflix (more on these later).


zuul过滤器的几点说明
过滤器类型分为三种， Pre Filter ， Route Filter ， Post Filter

Pre filters set up data in the RequestContext for use in filters downstream. 
The main use case is to set information required for route filters.

Route filters run after pre filters and make requests to other services. 
Much of the work here is to translate request and response data to and from the model required by the client. 

Post filters typically manipulate the response. 


超时的配置
经过实际测试得出，
ribbon: 
  eager-load:
    enabled: true
  ConnectTimeout: 3000
  ReadTimeout: 25000
这里的是在使用eureka下起作用的配置，出此之外其他的配置不起作用，但是最好吃与这里配置一致。

start "动态路由" java -jar -Dspring.profiles.active=dev -Xmx300m ldszuul.jar

增加了yml的profiles之后需要在mvn命令后携带参数，已传递给TEST模块进行测试。

mvn clean package -Dspring.profiles.active=prod