private void UpdateActivePartition()
{
lock (_activePartitionUpdateLock) {
if (_activePartition == null || DateTimeOffset.UtcNow - _activePartition.Created >= _partitionInterval)
{
// Update the active partition.
_activePartition = new TemporalPartition(_partitionBasePath, _partitionOpenOrCreateCallback);
_partitions.Enqueue(_activePartition);
}
}
}
/// <summary>
/// Initializes a new instance of the <see cref="T:LibWhipLru.Cache.PartitionedTemporalGuidCache"/> class.
/// </summary>
public PartitionedTemporalGuidCache(
string partitionBasePath,
TimeSpan partitionInterval,
Action <string> partitionOpenOrCreateCallback,
Action <string> partitionDeletionCallback,
Action <Guid, string, string> partitionTransferAssetCallback,
Func <string, Dictionary <Guid, uint> > partitionFoundCallback
)
{
if (string.IsNullOrWhiteSpace(partitionBasePath))
{
throw new ArgumentNullException(nameof(partitionBasePath), "Cannot be null, empty, or whitespace.");
}
if (partitionInterval < MIN_PARTITION_INTERVAL)
{
throw new ArgumentOutOfRangeException(nameof(partitionInterval), $"Cannot be less than {MIN_PARTITION_INTERVAL.TotalSeconds} seconds.");
}
_partitionBasePath = partitionBasePath;
_partitionInterval = partitionInterval;
_partitionOpenOrCreateCallback = partitionOpenOrCreateCallback ?? throw new ArgumentNullException(nameof(partitionOpenOrCreateCallback));
_partitionDeletionCallback = partitionDeletionCallback ?? throw new ArgumentNullException(nameof(partitionDeletionCallback));
_partitionTransferAssetCallback = partitionTransferAssetCallback ?? throw new ArgumentNullException(nameof(partitionTransferAssetCallback));
if (partitionFoundCallback == null)
{
throw new ArgumentNullException(nameof(partitionFoundCallback));
}
_cache = new ConcurrentDictionary <Guid, MetaAsset>();
_partitions = new ConcurrentQueue <TemporalPartition>();
// Restore from disk, if there's something to restore from.
foreach (var dbPath in Directory.EnumerateFileSystemEntries(partitionBasePath, "*", SearchOption.TopDirectoryOnly))
{
var assetsFound = partitionFoundCallback(dbPath);
if ((assetsFound?.Count ?? 0) > 0)
{
var partition = new TemporalPartition(dbPath);
_partitions.Enqueue(partition);
// Will wind up restoring assets that were previously "purged" as the per-item purge operation only removes the ID from active memory.
// Currently this is acceptible behavior as the per-item purge is only expectd to be used to clean up inconsistencies by purging the ID then adding a fresh copy.
// Everything else will just eventually fall out the LRU process.
foreach (var asset in assetsFound)
{
_cache.AddOrUpdate(
asset.Key,
assetId => new MetaAsset { // add
Id = assetId,
Partition = partition,
Size = asset.Value
},
(assetId, oldMeta) => { // update
oldMeta.Partition = partition;
oldMeta.Size = asset.Value;
return(oldMeta);
}
);
}
}
}
UpdateActivePartition();
}
