// Notification raised before ADAL accesses the cache.
// This is your chance to update the in-memory copy from the DB, if the in-memory version is stale
void BeforeAccessNotification(TokenCacheNotificationArgs args)
{
if (Cache == null)
{
// first time access
Cache = db.UserTokenCacheList.FirstOrDefault(c => c.webUserUniqueId == User);
}
else
{ // retrieve last write from the DB
var status = from e in db.UserTokenCacheList
where (e.webUserUniqueId == User)
select new
{
LastWrite = e.LastWrite
};
// if the in-memory copy is older than the persistent copy
if (status.First().LastWrite > Cache.LastWrite)
// read from from storage, update in-memory copy
{
Cache = db.UserTokenCacheList.FirstOrDefault(c => c.webUserUniqueId == User);
}
}
this.Deserialize((Cache == null) ? null : Cache.cacheBits);
}