/// <summary>
/// Asynchronously loads snapshot with the highest sequence number for a persistent actor/view matching specified criteria.
/// </summary>
protected async override Task <SelectedSnapshot> LoadAsync(string persistenceId, SnapshotSelectionCriteria criteria)
{
ServiceEventSource.Current.Message($"Entering ServiceFabricSnapshotStore.{nameof(LoadAsync)} PersistenceId: {persistenceId} ");
SnapshotEntry snapshot = null;
if (criteria.MaxSequenceNr > 0 && criteria.MaxSequenceNr < long.MaxValue)
{
var MaxNumberkey = $"{persistenceId}_{criteria.MaxSequenceNr}";
using (var tx = this.StateManager.CreateTransaction())
{
ServiceEventSource.Current.Message($"{persistenceId} ");
var snapshots = await this.StateManager.GetOrAddAsync <IReliableDictionary <string, SnapshotEntry> >(persistenceId);
var snapshotStorageCurrentHighSequenceNumber = await this.StateManager.GetOrAddAsync <IReliableDictionary <string, long> >("SnapshotStorageCurrentHighSequenceNumber");
var maxSequenceNumberConditional = await snapshotStorageCurrentHighSequenceNumber.TryGetValueAsync(tx, persistenceId);
if (maxSequenceNumberConditional.HasValue)
{
var MaxSequenceNumber = maxSequenceNumberConditional.Value;
var ret = await snapshots.TryGetValueAsync(tx, $"{persistenceId}_{MaxSequenceNumber}");
snapshot = ret.HasValue ? ret.Value : null;
await tx.CommitAsync();
SelectedSnapshot ss = new SelectedSnapshot(new SnapshotMetadata(persistenceId, snapshot.SequenceNr), snapshot);
return(ss);
}
}
}
return(null);
}
public SelectedSnapshot Map(SnapshotEntry e)
{
if (e == null)
{
return(null);
}
var persistenceId = e.PersistenceId;
var sequenceNr = e.SequenceNr;
var timestamp = e.Timestamp;
var metadata = new SnapshotMetadata(persistenceId, sequenceNr, timestamp);
var type = Type.GetType(e.SnapshotType, true);
var serializer = _serialization.FindSerializerForType(type);
var binary = e.Snapshot;
var snapshot = serializer.FromBinary(binary, type);
return(new SelectedSnapshot(metadata, snapshot));
}
/// <summary>
/// Asynchronously stores a snapshot with metadata as object in the reliable dictionary, saves the highest Sequence number
/// separatly to allow the last one to be found by sequence number.
/// </summary>
protected async override Task SaveAsync(SnapshotMetadata metadata, object snapshot)
{
ServiceEventSource.Current.Message($"Entering ServiceFabricSnapshotStore.{nameof(SaveAsync)} PersistenceId: {metadata.PersistenceId} SequencNumer: {metadata.SequenceNr}");
var snapshotEntry = new SnapshotEntry
{
Id = metadata.PersistenceId + "_" + metadata.SequenceNr,
PersistenceId = metadata.PersistenceId,
SequenceNr = metadata.SequenceNr,
Snapshot = snapshot,
Timestamp = metadata.Timestamp.Ticks
};
var snapshotEntryId = metadata.PersistenceId + "_" + metadata.SequenceNr;
using (var tx = this.StateManager.CreateTransaction())
{
var snapshotStorageCurrentHighSequenceNumber = await this.StateManager.GetOrAddAsync <IReliableDictionary <string, long> >("SnapshotStorageCurrentHighSequenceNumber");
var resultCurrentHighSquenceNumber = await snapshotStorageCurrentHighSequenceNumber.AddOrUpdateAsync(tx, metadata.PersistenceId, metadata.SequenceNr, (ssschsn, lng) => metadata.SequenceNr);
ServiceEventSource.Current.Message($"resultCurrentHighSquenceNumber: {resultCurrentHighSquenceNumber}");
var snapshots = await this.StateManager.GetOrAddAsync <IReliableDictionary <string, SnapshotEntry> >(metadata.PersistenceId);
var resultSnapshotAdd = await snapshots.GetOrAddAsync(tx, snapshotEntry.Id, ssid => snapshotEntry);
ServiceEventSource.Current.Message($"resultSnapshotAdd: {resultSnapshotAdd}");
await tx.CommitAsync();
ServiceEventSource.Current.Message($"Leaving {nameof(SaveAsync)} PersistenceId: {metadata.PersistenceId} SequencNumer: {metadata.SequenceNr}");
}
return;
}
