public override void SetupInvalidation(FederationCacheManager manager, string key)
        {
            manager.AddKeyToInvalidateOnTopicsInNamespaceChange(key, Namespace);

            /// For now we take a very aggressive invalidation approach that says that whenever
            /// the list of namespaces changes, we invalidate all cached topic lists.  This is because
            /// we dont' yet do the work to be more granular (e.g., figure out when a namespace is added
            /// or removed exactly which namespaces are impacted).  This will likely cause a near flushing of
            /// the cache when namespaces are added or removed, but that should be pretty rare.  if it
            /// becomes a serious problem, we can enhance this to be more granular.

            manager.AddKeyToInvalidateOnFederationNamespacesChange(key);
        }
 public override void SetupInvalidation(FederationCacheManager manager, string key)
 {
     manager.AddKeyToInvalidateOnFederationNamespacesChange(key);
 }