protected override async Task <SelectedSnapshot> LoadAsync(string persistenceId,
SnapshotSelectionCriteria criteria)
{
if (criteria.Equals(SnapshotSelectionCriteria.None))
{
return(null);
}
var streamName = GetStreamName(persistenceId);
if (!criteria.Equals(SnapshotSelectionCriteria.Latest))
{
var result = await FindSnapshot(streamName, criteria.MaxSequenceNr, criteria.MaxTimeStamp);
return(result.Snapshot);
}
var slice = await _conn.ReadStreamEventsBackwardAsync(streamName, StreamPosition.End, 1, false);
if (slice == null || slice.Status != SliceReadStatus.Success || !slice.Events.Any())
{
return(null);
}
return(slice.Events.Select(_snapshotAdapter.Adapt).First());
}
protected void AssertStreamTail(string streamId, params string[] events)
{
#if DEBUG
var result = _conn.ReadStreamEventsBackwardAsync(streamId, -1, events.Length, true, _admin).Result;
switch (result.Status)
{
case SliceReadStatus.StreamDeleted:
Assert.Fail("Stream '{0}' is deleted", streamId);
break;
case SliceReadStatus.StreamNotFound:
Assert.Fail("Stream '{0}' does not exist", streamId);
break;
case SliceReadStatus.Success:
var resultEventsReversed = result.Events.Reverse().ToArray();
if (resultEventsReversed.Length < events.Length)
DumpFailed("Stream does not contain enough events", streamId, events, result.Events);
else
{
for (var index = 0; index < events.Length; index++)
{
var parts = events[index].Split(new char[] { ':' }, 2);
var eventType = parts[0];
var eventData = parts[1];
if (resultEventsReversed[index].Event.EventType != eventType)
DumpFailed("Invalid event type", streamId, events, resultEventsReversed);
else
if (resultEventsReversed[index].Event.DebugDataView != eventData)
DumpFailed("Invalid event body", streamId, events, resultEventsReversed);
}
}
break;
}
#endif
}
public override async Task <long> ReadHighestSequenceNrAsync(string persistenceId, long fromSequenceNr)
{
try
{
var slice = await _conn.ReadStreamEventsBackwardAsync(persistenceId, StreamPosition.End, 1, false);
long sequence = 0;
if (slice.Events.Any())
{
var @event = slice.Events.First();
var adapted = _eventAdapter.Adapt(@event);
sequence = adapted.SequenceNr;
}
else
{
var metadata = await _conn.GetStreamMetadataAsync(persistenceId);
if (metadata.StreamMetadata.TruncateBefore != null)
{
sequence = metadata.StreamMetadata.TruncateBefore.Value;
}
}
return(sequence);
}
catch (Exception e)
{
_log.Error(e, e.Message);
throw;
}
}
public async Task read_stream_backward_respects_max_count()
{
var res = await _connection.ReadStreamEventsBackwardAsync(Stream, -1, 100, false);
Assert.AreEqual(SliceReadStatus.Success, res.Status);
Assert.AreEqual(3, res.Events.Length);
Assert.AreEqual(_testEvents.Skip(2).Select(x => x.EventId).ToArray(),
res.Events.Reverse().Select(x => x.Event.EventId).ToArray());
}
public async Task SaveAsync <T>(T aggregate) where T : AggregateRoot, new()
{
var changes = aggregate.GetChanges()
.Select((change) => GetEventDataByEvent(change))
.ToArray();
if (!changes.Any())
{
return;
}
var streamName = GetStreamName <T>(aggregate, aggregate.Id.ToString());
try
{
await _eventStoreConnection.AppendToStreamAsync(streamName, aggregate.Version, changes, null);
}
catch (WrongExpectedVersionException)
{
var page = await _eventStoreConnection.ReadStreamEventsBackwardAsync(streamName, -1, 1, false, null);
_logger.LogError("Version failed. Stream: {Stream}. Expected Version: {Version}. Last Version: {LastEventNumber}",
page.Stream, page.Status, aggregate.Version, page.LastEventNumber);
throw new AggregateVersionFailedException(page.Stream, aggregate.Version, page.LastEventNumber);
}
}
protected IEnumerable <dynamic> GetDataByStreamName(string streamName)
{
StreamEventsSlice eventCollection;
using (IEventStoreConnection connection = EventStoreConnectionHelper.GetEventStoreConnection())
{
eventCollection = connection.ReadStreamEventsBackwardAsync(streamName, StreamPosition.End, 1, false).Result;
}
var jsonSerialiserSettings = EventDeserialiser.GetSerialisationSettings();
var encoder = new UTF8Encoding();
return
((
(
(IEnumerable <dynamic>)eventCollection.Events
.Select(e => JsonConvert.DeserializeObject(((dynamic)encoder.GetString(e.Event.Data)), jsonSerialiserSettings))
.SingleOrDefault()
)
??
(
Enumerable.Empty <dynamic>()
)
)
.Select(x => x.Value));
}
public static async Task <(object Event, long Version)> ReadLastEvent(this IEventStoreConnection connection,
string streamName, Func <string, Type> stringToType)
{
try
{
var slice = await connection
.ReadStreamEventsBackwardAsync(streamName, StreamPosition.End, 1, true)
.ConfigureAwait(false);
if (slice.Status == SliceReadStatus.StreamDeleted || slice.Status == SliceReadStatus.StreamNotFound)
{
return(null, -1);
}
if (!slice.Events.Any())
{
return(null, 0);
}
var @event = Deserialize(slice.Events.First(), stringToType);
return(@event.@event, @event.index);
}
catch (Exception e)
{
Log.LogError(e, "Cannot read last event from stream {stream}: {message}", streamName, e.Message);
throw;
}
}
/// <summary>
/// Get the Last published event
/// </summary>
/// <param name="connection">connection to ES</param>
/// <param name="accountStream">Name of the stream</param>
/// <returns>json string of the last event</returns>
public static string GetLastEvent(IEventStoreConnection connection, string accountStream)
{
if (AccountManager.StreamExits(connection, accountStream))
{
var eventsStream = connection.ReadStreamEventsBackwardAsync(accountStream, 0, 1, true).Result;
var lastEventNr = eventsStream.LastEventNumber;
eventsStream = connection.ReadStreamEventsBackwardAsync(accountStream, lastEventNr, 1, true).Result;
var lastEvent = eventsStream.Events[0].Event;
var json = Encoding.UTF8.GetString(lastEvent.Data);
return(json);
}
else
{
return(null);
}
}
public async Task <CompareablePosition> GetCheckpoint(string processId, CancellationToken ct, string bucketId = null)
{
int streamPosition = StreamPosition.End;
var streamName = GetStreamId(processId, bucketId);
do
{
if (ct.IsCancellationRequested)
{
return(new CompareablePosition());
}
var slice = await _connection.ReadStreamEventsBackwardAsync(streamName, streamPosition, 1, false);
if (slice.Status != SliceReadStatus.Success || slice.Events.Length == 0)
{
return(new CompareablePosition());
}
var resolvedEvent = slice.Events[0];
var checkpointReached = _serializer.DeserializeEventData(resolvedEvent) as CheckpointReached;
if (checkpointReached != null)
{
return(new CompareablePosition(checkpointReached.CheckpointToken.ParsePosition()));
}
streamPosition = resolvedEvent.Event.EventNumber - 1;
} while(streamPosition >= 0);
return(new CompareablePosition());
}
public static string GetLastEvent(this IEventStoreConnection connection, string streamName)
{
if (StreamExits(connection, streamName))
{
var eventsStream = connection.ReadStreamEventsBackwardAsync(streamName, 0, 1, true).Result;
var lastEventNr = eventsStream.LastEventNumber;
eventsStream = connection.ReadStreamEventsBackwardAsync(streamName, lastEventNr, 1, true).Result;
var lastEvent = eventsStream.Events[0].Event;
var json = Encoding.UTF8.GetString(lastEvent.Data);
return(json);
}
else
{
return(null);
}
}
public List <EventstoreEvent> ReadLastEvents(string streamName, int eventsToRead)
{
var result = _connection.ReadStreamEventsBackwardAsync(streamName, StreamPosition.End, eventsToRead, false).Result;
var mappedEvents = result.Events.Select(MapEventstoreEvent);
return(mappedEvents.Reverse().ToList());
}
public async Task TheExampleCanRun()
{
await _eventStoreConnection.ConnectAsync();
await WriteBytesToStream("test-stream", "testEvent", "some data");
var streamEvents = await
_eventStoreConnection.ReadStreamEventsBackwardAsync("test-stream", StreamPosition.End, 1, false);
var returnedEvent = streamEvents.Events[0].Event;
var returnedData = Encoding.UTF8.GetString(returnedEvent.Data);
var returnedMetaData = Encoding.UTF8.GetString(returnedEvent.Metadata);
Assert.Equal("some data", returnedData);
Assert.Equal("some metadata", returnedMetaData);
}
public async Task <IEnumerable <EventLog> > LoadLogs <T>(int aggregateId, int take) where T : Aggregate, new()
{
if (aggregateId < 0)
{
throw new ArgumentException("Value cannot be below zero", nameof(aggregateId));
}
var aggregate = new T();
var streamName = GetStreamName(aggregate, aggregateId);
var results = new List <EventLog>();
var page = await _eventStore.ReadStreamEventsBackwardAsync(
streamName,
StreamPosition.End,
take,
false);
if (page.Events.Length > 0)
{
results.AddRange(page.Events.Select(@event =>
{
return(new EventLog
{
EventParameters = JsonSerializer.Deserialize(
Encoding.UTF8.GetString(@event.OriginalEvent.Data),
Type.GetType(Encoding.UTF8.GetString(@event.OriginalEvent.Metadata))),
EventType = @event.Event.EventType,
TimeStamp = @event.Event.Created
});
}));
}
return(results);
}
public T BuscarSnapshotPor <T>(Guid entidadeId) where T : Snapshot
{
var stream = string.Format("{0}-ss", entidadeId);
var ev = conexao.ReadStreamEventsBackwardAsync(stream, StreamPosition.End, 1, false).Result;
return(ev.Events.Any() ? (T)Deserialize(ev.Events.Single()) : null);
}
private static async Task AppendToStream <T>(ConcurrentUnitOfWork uow, IEventStoreConnection connection, Now now, IStreamNameResolver getStreamName) where T : IAggregateRootEntity
{
foreach (Aggregate aggregate in uow.GetChanges())
{
EventData[] changes = aggregate.Root.GetChanges()
.Select(@event => new EventData(
Guid.NewGuid(),
@event.GetType().TypeQualifiedName(),
true,
Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(@event)),
Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(new EventMetadata
{
TimeStamp = now(),
AggregateType = typeof(T).Name,
AggregateAssemblyQualifiedName = typeof(T).AssemblyQualifiedName,
IsSnapshot = false
}))
)).ToArray();
try
{
await connection.AppendToStreamAsync(getStreamName.Resolve(aggregate.Identifier), aggregate.ExpectedVersion, changes);
}
catch (WrongExpectedVersionException)
{
StreamEventsSlice page = await connection.ReadStreamEventsBackwardAsync(aggregate.Identifier, -1, 1, false);
throw new WrongExpectedStreamVersionException(
$"Failed to append stream {aggregate.Identifier} with expected version {aggregate.ExpectedVersion}. " +
$"{(page.Status == SliceReadStatus.StreamNotFound ? "Stream not found!" : $"Current Version: {page.LastEventNumber}")}");
}
}
}
private async IAsyncEnumerable <StoredEvent> QueryReverseAsync(string streamName, long sliceStart, long take = int.MaxValue,
[EnumeratorCancellation] CancellationToken ct = default)
{
var taken = take;
StreamEventsSlice currentSlice;
do
{
currentSlice = await connection.ReadStreamEventsBackwardAsync(streamName, sliceStart, ReadPageSize, true);
if (currentSlice.Status == SliceReadStatus.Success)
{
sliceStart = currentSlice.NextEventNumber;
foreach (var resolved in currentSlice.Events.OrderByDescending(x => x.Event.EventNumber))
{
var storedEvent = Formatter.Read(resolved, prefix, serializer);
yield return(storedEvent);
if (taken == take)
{
break;
}
taken++;
}
}
}while (!currentSlice.IsEndOfStream && !ct.IsCancellationRequested && taken < take);
}
/// <summary>
/// Check if stream exists
/// </summary>
/// <param name="connection">connection to ES</param>
/// <param name="streamName">Name of the stream</param>
/// <returns>True if stream exists</returns>
public static bool StreamExits(IEventStoreConnection connection, string streamName)
{
var lastEventsStream = connection.ReadStreamEventsBackwardAsync(streamName.ToLower(), 0, 1, false).Result;
SliceReadStatus status = lastEventsStream.Status;
return(status == 0);
}
#pragma warning disable 1998
protected async Task AssertStreamTail(string streamId, params string[] events)
{
#pragma warning restore 1998
#if DEBUG
await Task.Delay(TimeSpan.FromMilliseconds(500));
var result = await _conn.ReadStreamEventsBackwardAsync(streamId, -1, events.Length, true, _admin);
switch (result.Status)
{
case SliceReadStatus.StreamDeleted:
Assert.Fail("Stream '{0}' is deleted", streamId);
break;
case SliceReadStatus.StreamNotFound:
Assert.Fail("Stream '{0}' does not exist", streamId);
break;
case SliceReadStatus.Success:
var resultEventsReversed = result.Events.Reverse().ToArray();
if (resultEventsReversed.Length < events.Length)
{
DumpFailed("Stream does not contain enough events", streamId, events, result.Events);
}
else
{
for (var index = 0; index < events.Length; index++)
{
var parts = events[index].Split(new char[] { ':' }, 2);
var eventType = parts[0];
var eventData = parts[1];
if (resultEventsReversed[index].Event.EventType != eventType)
{
DumpFailed("Invalid event type", streamId, events, resultEventsReversed);
}
else if (resultEventsReversed[index].Event.DebugDataView() != eventData)
{
DumpFailed("Invalid event body", streamId, events, resultEventsReversed);
}
}
}
break;
}
#endif
}
public async Task Delete(TId selector)
{
var id = selector.ToString();
var eventsTail = await connection.ReadStreamEventsBackwardAsync(id, 0, 1, false);
var expectedVersion = eventsTail.LastEventNumber;
await connection.DeleteStreamAsync(id, expectedVersion);
}
public Func <Task <SerializedEvent> > ReadEventsBackwards(string stream, int batchSize, long maxToRead, Action <string> onNotFound, bool resolveLinks = true)
{
return(new EventReader(
position => _connection.ReadStreamEventsBackwardAsync(stream, position, batchSize, resolveLinks),
() => onNotFound(stream),
StreamPosition.End,
maxToRead).Next);
}
private static async Task <StreamEventsSlice> ReadStreamEventsBackwardsAsync(this IEventStoreConnection connection, string streamName, int lastEventNumber)
{
return(await connection.ReadStreamEventsBackwardAsync(
streamName,
lastEventNumber,
PageSize, false,
EventStoreCredentials.Default));
}
public async Task <StreamEventsSlice> GetCurrentSlice(IEventStoreConnection connection, long streamPosition, bool resolveLinkTos)
{
var currentSlice = await connection.ReadStreamEventsBackwardAsync(streamId, streamPosition, SliceSize, resolveLinkTos);
nextSliceStart = currentSlice.NextEventNumber;
return(currentSlice);
}
private static long GetLatestStreamPosition(IEventStoreConnection connection, string streamId)
{
var position = connection
.ReadStreamEventsBackwardAsync(streamId, StreamPosition.End, 1, true)
.Result?.LastEventNumber ?? 0;
return(position);
}
public ActionResult CardData()
{
string NodeName = "none";
CardVM card = null;
int cardNo;
DateTime occurred;
if (Session["Node"] != null)
{
NodeName = Session["Node"].ToString();
}
if (NodeName != "none")
{
using (IEventStoreConnection connection = EventStoreConnection.Create(new IPEndPoint(IPAddress.Loopback, 1113)))
{
connection.ConnectAsync();
var result = Task.Run(() => connection.ReadStreamEventsBackwardAsync(NodeName, StreamPosition.End, 1, false));
Task.WaitAll();
var resultData = result.Result;
foreach (var Event in resultData.Events)
{
string strData = Encoding.UTF8.GetString(Event.Event.Data);
string strMeta = Encoding.UTF8.GetString(Event.Event.Metadata);
var datetimeConverter = new IsoDateTimeConverter {
DateTimeFormat = "dd/MM/yyyy"
};
dynamic Eventdata = JsonConvert.DeserializeObject(strData);
dynamic EventMetadata = JsonConvert.DeserializeObject(strMeta);
if (Event.Event.EventType == "checkIn" || Event.Event.EventType == "checkOut")
{
cardNo = (int)EventMetadata.SelectToken("CardNumber");
if (cardNo != 0)
{
using (DB db = new DB())
{
card = new CardVM();
var cardInfo = db.CardInfoes.Where(x => x.CardNumber == cardNo).FirstOrDefault();
card.Id = cardInfo.Id;
card.Name = cardInfo.Name;
card.Title = cardInfo.Title;
card.Department = cardInfo.Department;
card.ImageName = cardInfo.ImageName;
card.CardNumber = cardInfo.CardNumber;
}
}
else
{
card = null;
}
occurred = (DateTime)Eventdata.SelectToken("occurred");
}
}
}
}
ViewBag.NodeName = NodeName;
return(PartialView(card));
}
public static void EditJsonStream <T>(this IEventStoreConnection connection, IEventType <T> eventType) where T : class
{
var eventsStream = connection.ReadStreamEventsBackwardAsync(eventType.EditStreamName, 0, 1, true).Result;
var lastEventNr = eventsStream.LastEventNumber;
var json = Newtonsoft.Json.JsonConvert.SerializeObject(eventType.Data);
var myEvent = new EventData(Guid.NewGuid(), eventType.EventType, true, Encoding.UTF8.GetBytes(json), null);
connection.AppendToStreamAsync(eventType.EditStreamName, lastEventNr, myEvent).Wait();
}
public EventStoreRepository(IEventStoreConnection connection)
{
this.connection = connection;
getStreamName = (type, guid) => $"{type.Name}-{guid}"; // todo make this a delegate
log = LogManager.GetLogger(GetType());
eventStreamReaders = new Dictionary <ReadDirection, Func <string, int, int, Task <StreamEventsSlice> > >()
{
[ReadDirection.Forwards] = async(s, i, c) => await connection.ReadStreamEventsForwardAsync(s, i, c, resolveLinkTos : true).ConfigureAwait(false),
[ReadDirection.Backwards] = async(s, i, c) => await connection.ReadStreamEventsBackwardAsync(s, i, c, true).ConfigureAwait(false)
};
}
private async Task <ItemScanned> MostRecentItemScannedIntoBasket(Guid correlationId)
{
var slice = await
_eventStoreConnection.ReadStreamEventsBackwardAsync($"basket-{correlationId}", StreamPosition.End, 1, false);
Assert.Equal(SliceReadStatus.Success, slice.Status);
var returnedEvent = slice.Events[0].Event;
return(JsonConvert.DeserializeObject <ItemScanned>(Encoding.UTF8.GetString(returnedEvent.Data)));
}
/// <summary>
/// Update a message to show it is dispatched
/// </summary>
/// <param name="id">The id of the message to update</param>
/// <param name="dispatchedAt">When was the message dispatched, defaults to UTC now</param>
/// <param name="args">Additional parameters required for search, if any</param>
/// <param name="cancellationToken">Allows the sender to cancel the request pipeline. Optional</param>
public async Task MarkDispatchedAsync(Guid id, DateTime?dispatchedAt = null, Dictionary <string, object> args = null,
CancellationToken cancellationToken = default)
{
var stream = GetStreamFromArgs(args);
StreamEventsSlice slice;
var startPos = (long)StreamPosition.End;
long? nextEventNumber = null;
RecordedEvent resolvedEvent;
bool found = false;
do
{
slice = await _eventStore.ReadStreamEventsBackwardAsync(stream, startPos, 100, true);
startPos = slice.NextEventNumber;
if (nextEventNumber is null)
{
nextEventNumber = (await _eventStore.ReadStreamEventsBackwardAsync(stream, StreamPosition.End, 1, true)).LastEventNumber;
}
resolvedEvent = slice.Events.FirstOrDefault(e => e.Event.EventId == id).Event;
if (resolvedEvent != null)
{
found = true;
}
} while (!found && !slice.IsEndOfStream);
if (resolvedEvent is null)
{
return;
}
var message = EventStoreMessageReader.ConvertEventToMessage(resolvedEvent, stream, dispatchedAt, nextEventNumber.Value);
var eventData = EventStoreMessageWriter.CreateEventData(message);
await _eventStore.AppendToStreamAsync(stream, nextEventNumber.Value, eventData);
}
public static async Task <StreamSize> GetStreamSize(
this IEventStoreConnection connection, string stream
)
{
var last = await connection.ReadStreamEventsBackwardAsync(
stream,
StreamPosition.End,
1,
false
).ConfigureAwait(false);
return(new StreamSize(last.LastEventNumber));
}
private async Task <Snapshot> GetSnapshot(string sku)
{
var streamName = GetSnapshotStreamName(sku);
var slice = await _connection.ReadStreamEventsBackwardAsync(streamName, StreamPosition.End, 1, false);
if (slice.Events.Any())
{
var evnt = slice.Events.First();
var json = Encoding.UTF8.GetString(evnt.Event.Data);
return(JsonConvert.DeserializeObject <Snapshot>(json));
}
return(new Snapshot());
}
private static void ReadStreamEventsBackward(IEventStoreConnection connection)
{
StreamEventsSlice slice = connection.ReadStreamEventsBackwardAsync("test-stream", StreamPosition.End, 10, false).Result;
if (slice.Events.Length > 0)
{
Console.WriteLine("id: " + slice.Events[0].Event.EventId);
string data = Encoding.UTF8.GetString(slice.Events[0].Event.Data);
Console.WriteLine("data: " + data);
string metadata = Encoding.UTF8.GetString(slice.Events[0].Event.Metadata);
Console.WriteLine("metadata: " + metadata);
}
}