Client Data Synchronization with
WaitForUpdatesEx
To maintain a client-side representation of server object state
(by monitoring the properties for the inventory), use the
CreateFilter
and WaitForUpdatesEx
methods.
WaitForUpdatesEx
supports an incremental retrieval
model. When the
WaitForUpdatesEx
call
returns an UpdateSet
, apply the updates as patches to the properties of
managed objects in your client-side copy. In some circumstances, the server can return
redundant updates. If the client response includes side effects in addition to updating client
data, the additional actions should be idempotent.The
WaitForUpdatesEx
call
cannot guarantee synchronization between client and server in the presence of rapid server
data changes, but when the server state is static calls to WaitForUpdatesEx
result in eventual synchronization. If you create additional instances of
PropertyCollector
, each instance uses independent version IDs for data
synchronization. You should maintain a separate client copy of server data for each
PropertyCollector
instance when you use
WaitForUpdatesEx
.The filters you use for
incremental retrieval persist for the duration of the session or until you
destroy them.