diff options
Diffstat (limited to 'sync/notifier/sync_notifier.h')
-rw-r--r-- | sync/notifier/sync_notifier.h | 40 |
1 files changed, 37 insertions, 3 deletions
diff --git a/sync/notifier/sync_notifier.h b/sync/notifier/sync_notifier.h index 80b97b8..9191b90 100644 --- a/sync/notifier/sync_notifier.h +++ b/sync/notifier/sync_notifier.h @@ -22,12 +22,46 @@ class SyncNotifier { SyncNotifier() {} virtual ~SyncNotifier() {} - // Updates the set of ObjectIds associated with a given |handler|. - // Passing an empty ObjectIdSet will unregister |handler|. - // There should be at most one handler registered per object id. + // Clients should follow the pattern below: + // + // When starting the client: + // + // notifier->RegisterHandler(client_handler); + // + // When the set of IDs to register changes for the client during its lifetime + // (i.e., between calls to RegisterHandler(client_handler) and + // UnregisterHandler(client_handler): + // + // notifier->UpdateRegisteredIds(client_handler, client_ids); + // + // When shutting down the client for browser shutdown: + // + // notifier->UnregisterHandler(client_handler); + // + // Note that there's no call to UpdateRegisteredIds() -- this is because the + // invalidation API persists registrations across browser restarts. + // + // When permanently shutting down the client, e.g. when disabling the related + // feature: + // + // notifier->UpdateRegisteredIds(client_handler, ObjectIdSet()); + // notifier->UnregisterHandler(client_handler); + + // Starts sending notifications to |handler|. |handler| must not be NULL, + // and it must already be registered. + virtual void RegisterHandler(SyncNotifierObserver* handler) = 0; + + // Updates the set of ObjectIds associated with |handler|. |handler| must + // not be NULL, and must already be registered. An ID must be registered for + // at most one handler. virtual void UpdateRegisteredIds(SyncNotifierObserver* handler, const ObjectIdSet& ids) = 0; + // Stops sending notifications to |handler|. |handler| must not be NULL, and + // it must already be registered. Note that this doesn't unregister the IDs + // associated with |handler|. + virtual void UnregisterHandler(SyncNotifierObserver* handler) = 0; + // SetUniqueId must be called once, before any call to // UpdateCredentials. |unique_id| should be a non-empty globally // unique string. |