private SessionData CheckForNewer(string sessionId, SessionData data)
{
string cacheKey = _sessionKeyFormat.GetPrimaryKey(sessionId);
// try if there is fresher copy
// This happens when a node goes up or down
if (AssignPrimaryBackupNodes(cacheKey))
{
var newData = _client.Get<SessionData>(cacheKey);
if (newData == null || data.SavedAt > newData.SavedAt)
{
// If not found or older, that means this client hit the key first
// so relocate session for next call
Store(sessionId, data, TimeSpan.FromMinutes(data.Timeout));
}
else
{
// else found newer, that means some other client already updated this
data = newData;
}
}
return data;
}
public void Store(string sessionId, SessionData cacheItem, TimeSpan timeout)
{
var cacheKey = _sessionKeyFormat.GetPrimaryKey(sessionId);
AssignPrimaryBackupNodes(cacheKey);
cacheItem.SavedAt = DateTime.UtcNow.Ticks;
_client.Store(StoreMode.Set, cacheKey, cacheItem, timeout);
if (IsBackupEnabled()) // backup
{
var backupKey = _sessionKeyFormat.GetBackupKey(sessionId);
_client.Store(StoreMode.Set, backupKey, cacheItem, timeout);
}
}