As fetching is done with the parameters of the refresh request, other variants of the same content will not be touched.
Every client request is checked against this blacklist.
If the request happens to match blacklisted content, fresh content is fetched from the application, stored in the proxy server and returned to the client.
Although proxy servers may handle invalidation differently, the effect is always the same: the next time a client requests the data, he or she gets a new version instead of the outdated one.
Cache invalidation gives you the best of both worlds: you can have very long TTLs, so when content changes little, it can be served from the cache because no requests to your application are required.
In a discussion with Chuck Todd for NBC Nightly News, Santorum repeated his support for a federal constitutional amendment banning same-sex marriage. Satorum thought same-sex marriage “was going to be a state issue,” the former senator, who has oftentalked up his “small government” philosophy, replied, “I think marriage has to be one thing for everybody.
The next time a client requests the URL, data is fetched from the application, stored in the proxy server, and returned to the client.
Santorum would do about those same-sex couples who are already married. “Well, their marriages would be invalid” because they would not be “consistent with the Constitution” replied Santorum. Santorum is being unfair, he added that he wanted to be “tolerant” but the “real consequences” of same-sex marriage meant that he had to take a firm stance.Instead of finding some compromise, you can have both with cache invalidation.When application data changes, the application takes care of invalidating its web representation as out-of-date.On that next request, the proxy will fetch a fresh copy from the application.HTTP caching is a great solution for improving the performance of your web application.The content is not just deleted from the cache, but is replaced with a new version fetched from the application.