System and method of providing web content using a proxy cache

A computing system comprising:

• one or more processors;
• a cache storage medium;
• non-transitory computer readable storage medium embodying programming instructions configurable to cause the one or more processors to implement using the cache storage medium a proxy cache, the proxy cache configured to:
• cache a cached object that is a copy of a cacheable object stored at a server, wherein the cached object observes an observable object for changes through the proxy keeping track of an observable relationship identified by the server via an observable parameter in a response message, wherein the observable relationship comprises the identity of an observable object that if modified would make one or more cached objects obsolete, wherein the observable object is stored at the server and the observable object is not the cacheable object;
• receive, from a client, a request to replace the observable object at the server with a new resource;
• forward, to the server, the request to replace the observable object with the new resource;
• receive, from the server after the server has replaced the observable object with the new resource, a response message that includes a notify parameter that identifies the observable object as having been changed;
• forward, by the proxy, the response message to the client;
• and
• invalidate the cached object that has been observing the observable object identified by the notify parameter;
• and
• not service a subsequent request from a client for the cacheable object from the cache storage medium.

A non-transitory computer readable storage medium encoded with programming instructions configurable to cause a processor to implement a proxy cache that performs a method, the method comprising:

• caching a cached object that is a copy of a cacheable object stored at a server in a cache storage medium, wherein the cached object observes an observable object for changes through the proxy keeping track of an observable relationship identified by the server via an observable parameter in a response message, wherein the observable relationship comprises the identity of an observable object that if modified would make one or more cached objects obsolete, wherein the observable object is stored at the server and the observable object is not the cacheable object;
• receiving, from a client, a request to replace the observable object at the server with anew resource;
• forwarding, to the server, the request to replace the observable object with the new resource;
• receiving, from the server after the server has replaced the observable object with the new resource, a response message that includes a notify parameter that identifies the observable object as having been changed;
• forwarding the response message to the client;
• and
• instructing the cache storage medium to invalidate the cached object that has been observing the observable object identified by the notify parameter, wherein the cache storage medium invalidates the cached object that has been observing the observable object;
• and
• wherein a subsequent request from a client for the cacheable object is not serviced from the cache storage medium.