public async Task <EventReadResult> ReadStreamAsync(long eventNumber)
{
const string appName = nameof(EventStoreSample);
IEventStoreConnection connection = await GetConnection();
return(await connection.ReadEventAsync("", eventNumber, false, EventStoreCredentials.Default));
}
public async Task <bool> Exists(int productId)
{
var stream = GetStreamName(productId);
var result = await _connection.ReadEventAsync(stream, 1, false);
return(result.Status != EventReadStatus.NoStream);
}
public async Task <bool> Exists <T, TId>(TId aggregateId)
{
var stream = GetStreamName <T, TId>(aggregateId);
var result = await _connection.ReadEventAsync(stream, 1, false);
return(result.Status != EventReadStatus.NoStream);
}
/// <inheritdoc />
public ulong GetOffset(EventHorizonKey key)
{
var result = _connection.ReadEventAsync(GetStreamForEventHorizonKey(key), StreamPosition.End, true).Result;
if (result.Event.HasValue)
{
return(_serializer.FromJsonBytes <ulong>(result.Event.Value.Event.Data));
}
return(0);
}
private static long?GetLastEventNumber(this IEventStoreConnection connection, string streamName)
{
var lastEvent = connection.ReadEventAsync(streamName, -1, false).Result;
if (lastEvent == null || lastEvent.Event == null)
{
return(null);
}
return(lastEvent.Event.Value.OriginalEventNumber);
}
/// <inheritdoc />
public CommittedEventVersion Get(EventProcessorId eventProcessorId)
{
var result = _connection.ReadEventAsync(GetStreamForEventProcessorId(eventProcessorId), StreamPosition.End, true).Result;
if (result.Event.HasValue)
{
return(_serializer.FromJsonBytes <CommittedEventVersion>(result.Event.Value.Event.Data));
}
return(CommittedEventVersion.None);
}
public async Task <bool> Exists <T, TId>(TId aggregateId)
{
if (aggregateId == null)
{
throw new ArgumentNullException(nameof(aggregateId));
}
var result = await connection.ReadEventAsync(GetStreamName <T, TId>(aggregateId), 1, false);
return(result.Status != EventReadStatus.NoStream);
}
private static long?GetLastEventNumber(this IEventStoreConnection connection, string streamName)
{
var lastEvent = connection.ReadEventAsync(streamName, -1, false, EventStoreCredentials.Default);
if (lastEvent == null || lastEvent.Result.Event == null)
{
return(null);
}
return(lastEvent.Result.EventNumber);
}
public static T GetLastEvent <T>(this IEventStoreConnection connection, string streamName) where T : class
{
var lastEvent = connection.ReadEventAsync(streamName, -1, false, EventStoreCredentials.Default);
if (lastEvent == null || lastEvent.Result.Event == null)
{
return(null);
}
return(lastEvent.Result.Event.Value.ParseJson <T>());
}
public long GetLastEventNumber()
{
try
{
var readEvent = _conn.ReadEventAsync(_stream, StreamPosition.End, true).Result;
return(readEvent.Event.Value.Event.EventNumber);
}
catch (Exception)
{
return(-1);
}
}
/// <inheritdoc />
public async Task <Snapshot> ReadSnapshot(object id, Type aggregateType)
{
var snapshot = await _connection.ReadEventAsync(StreamNameResolver.ResolveForSnapshot(id, aggregateType), StreamPosition.End, true);
if (NotAnySnapshotExists(snapshot))
{
return(await Task.FromResult <Snapshot>(null));
}
return((Snapshot)JsonConvert.DeserializeObject(
// ReSharper disable once PossibleInvalidOperationException
Encoding.UTF8.GetString(snapshot.Event.Value.Event.Data), TypeResolver.ResolveSnapshotType(snapshot.Event.Value.Event.EventType)));
}
public static T GetLastEvent <T>(this IEventStoreConnection connection, string streamName)
where T : class
{
if (connection == null)
{
throw new ArgumentNullException("connection");
}
var lastEvent = connection.ReadEventAsync(streamName, -1, false).Result;
if (lastEvent == null || lastEvent.Event == null)
{
return(null);
}
return(lastEvent.Event.Value.ParseJson <T>());
}
/// <inheritdoc />
public async Task TakeSnapshotIfNeed(IAggregateRoot aggregate)
{
var lastSnapshotVersion = -1L;
var lastSnapshot = await _connection.ReadEventAsync(StreamNameResolver.ResolveForSnapshot(aggregate), StreamPosition.End, true);
if (AnySnapshotExists(lastSnapshot))
{
lastSnapshotVersion = lastSnapshot.Event.GetValueOrDefault().OriginalEventNumber;
}
if (NeedToTakeSnapshot(aggregate, lastSnapshotVersion))
{
await TakeSnapshot(_connection, aggregate);
}
}
public async Task <EventFromStream> ReadEventAsync(IEventStoreConnection connection, string stream, long index)
{
var result = await connection.ReadEventAsync(stream, index, false);
if (ResultHasNoEvent(result))
{
return(new NoEventFound());
}
return(new LoadedEvent
{
Type = result.Event?.Event.EventType,
Data = result.Event?.Event.Data ?? new byte[] { }
});
}
public async Task <TEvent> ReadEventAsync <TEvent>(string streamName, int position) where TEvent : class
{
var result = await connection.ReadEventAsync(streamName, position, resolveLinkTos : true).ConfigureAwait(false);
if (!result.Event.HasValue)
{
throw new EventNotFoundException(streamName, position);
}
var originalEvent = result.Event.Value.OriginalEvent;
var evt = DeserializeEvent(originalEvent.Metadata, originalEvent.Data);
return(evt as TEvent);
}
public async Task <StreamReadResults> ReadFrom(string streamId, Func <IAmAStoredEvent, bool> predicate = null, StreamReadDirection direction = StreamReadDirection.Backwards, CancellationToken cancellationToken = default)
{
predicate ??= _ => true;
IAsyncEnumerable <StoredEvent> storedEvents;
if (direction == StreamReadDirection.Backwards)
{
var readResult = await connection.ReadStreamEventsBackwardAsync(streamId, StreamPosition.End, pageSize, true);
if (!StreamExists(readResult))
{
return(new StreamReadResults(EmptyReadResult, false, StoredEventPosition.FromInt64(-1)));
}
storedEvents = readResult.Events
// Trust me, resharper is wrong in this one. Event can be null
// ReSharper disable once ConditionIsAlwaysTrueOrFalse
.Where(e => e.Event != null)
.Select((e, _) => e.Event.ToStoredEvent(stateFactory))
.TakeWhile(e => e.DeserializedEvent is not EntitySoftDeleted)
.Where(e => predicate(e))
.ToAsyncEnumerable();
}
else
{
var readResult = await connection.ReadStreamEventsForwardAsync(streamId, StreamPosition.Start, pageSize, true);
if (!StreamExists(readResult))
{
return(new StreamReadResults(EmptyReadResult, false, StoredEventPosition.FromInt64(-1)));
}
storedEvents = readResult.Events
// Trust me, resharper is wrong in this one. Event can be null
// ReSharper disable once ConditionIsAlwaysTrueOrFalse
.Where(e => e.Event != null)
.Select((e, c) => e.Event.ToStoredEvent(stateFactory))
.Where(e => predicate(e))
.ToAsyncEnumerable();
}
var result = await connection.ReadEventAsync(streamId, StreamPosition.End, false);
var idx = result.Event?.OriginalEventNumber ?? -1;
return(new StreamReadResults(storedEvents, true, StoredEventPosition.FromInt64(idx)));
}
public Position Get()
{
var resolvedEvent = _connection.ReadEventAsync(StreamId, StreamPosition.End, false).Result.Event;
if (resolvedEvent == null)
{
return(_lastPosition);
}
var @event = SerializationUtils.DeserializeEvent(resolvedEvent.Value.Event);
var changed = @event as PositionChanged;
if (changed != null)
{
_lastPosition = new Position(changed.Commit, changed.Prepare);
}
return(_lastPosition);
}
public async Task <ISnapshot> GetSnapshot(String bucket, String stream)
{
Logger.DebugFormat("Getting snapshot for stream '{0}' in bucket '{1}'", stream, bucket);
var streamId = String.Format("{0}.{1}.{2}", bucket, stream, "snapshots");
if (_shouldCache)
{
var cached = _cache.RetreiveSnap(streamId);
if (cached != null)
{
return(cached);
}
}
var read = await _client.ReadEventAsync(streamId, StreamPosition.End, false);
if (read.Status != EventReadStatus.Success || !read.Event.HasValue)
{
return(null);
}
var @event = read.Event.Value.Event;
var descriptor = @event.Metadata.Deserialize(_settings);
var data = @event.Data.Deserialize(@event.EventType, _settings);
var snapshot = new Snapshot
{
EntityType = descriptor.EntityType,
Bucket = bucket,
Stream = stream,
Timestamp = descriptor.Timestamp,
Version = descriptor.Version,
Payload = data
};
if (_shouldCache)
{
_cache.CacheSnap(streamId, snapshot);
}
return(snapshot);
}
StreamVersionedValue <CommitSequenceNumber> GetNextCommitSequenceNumber()
{
var result = _connection.ReadEventAsync(GetStreamForCommit(), StreamPosition.End, true).Result;
ThrowIfStreamWasDeleted(GetStreamForCommit(), result);
if (result.Status == EventReadStatus.NoStream)
{
return(new StreamVersionedValue <CommitSequenceNumber>(GetStreamForCommit(), ExpectedVersion.NoStream, 0));
}
try
{
var metadata = _serializer.FromJsonBytes <EventMetadata>(result.Event.Value.Event.Metadata);
return(new StreamVersionedValue <CommitSequenceNumber>(GetStreamForCommit(), result.Event.Value.Event.EventNumber, metadata.Commit.Sequence + 1));
}
catch (Exception ex)
{
throw new CorruptedEventStore("Could not deserialize event metadata", ex);
}
}
public async Task <long?> GetLastPositionInStreamAsync(string streamId)
{
try
{
long?lastPosition = null;
var result = await _connection.ReadEventAsync(streamId, StreamPosition.End, false);
if (result.Status == EventReadStatus.Success)
{
if (result.Event.HasValue)
{
lastPosition = result.Event.Value.OriginalEventNumber;
}
}
return(lastPosition);
}
catch (Exception ex)
{
_logger.LogError(ex, "Exception while getting end of stream.");
throw;
}
}
public async Task <TAggregate?> AggregateAsync <TIdentity, TAggregate>(
TIdentity id,
AggregateConfiguration <TIdentity, TAggregate> configuration,
long?version = null,
CancellationToken cancellationToken = default
)
where TAggregate : Aggregate <TIdentity, TAggregate>
{
var stream = _streamNameResolver.Stream(id, configuration);
var createdResult = await _connection.ReadEventAsync(stream, StreamPosition.Start, false);
if (createdResult.Event == null)
{
return(null);
}
var createdResolvedEvent = createdResult.Event.Value;
var createdRecordedEvent = createdResolvedEvent.Event;
if (!configuration.Constructors.TryGetValue(createdRecordedEvent.EventType, out var constructor))
{
throw new InvalidOperationException(
$"Unrecognized construction event type: {createdRecordedEvent.EventType}"
);
}
var aggregate = constructor(id, _serializer, createdRecordedEvent.Data);
aggregate.Record(new RecordableEvent(createdRecordedEvent.EventNumber));
var applicators = configuration.Applicators;
long sliceStart = 1;
const int sliceSize = 100;
StreamEventsSlice slice;
do
{
slice = await _connection.ReadStreamEventsForwardAsync(stream, sliceStart, sliceSize, false);
foreach (var resolvedEvent in slice.Events)
{
var recordedEvent = resolvedEvent.Event;
if (version.HasValue && recordedEvent.EventNumber > version.Value)
{
return(aggregate);
}
if (applicators.TryGetValue(recordedEvent.EventType, out var applicator))
{
applicator(aggregate, _serializer, recordedEvent.Data);
aggregate.Record(new RecordableEvent(recordedEvent.EventNumber));
}
else
{
throw new InvalidOperationException(
$"Unexpected recorded event type: {recordedEvent.EventType}"
);
}
}
sliceStart = slice.NextEventNumber;
} while (!slice.IsEndOfStream);
return(aggregate);
}
public async Task <HealthCheckResult> CheckHealthAsync(CancellationToken cancellationToken = default(CancellationToken))
{
await connection.ReadEventAsync("test", 1, false);
return(new HealthCheckResult(true, "Querying test event from event store."));
}
public async Task <bool> Exists(string streamName)
{
var result = await _connection.ReadEventAsync(streamName, 1, false);
return(result.Status != EventReadStatus.NoStream);
}
public void throw_if_stream_id_is_null()
{
Assert.Throws <ArgumentNullException>(() => _conn.ReadEventAsync(null, 0, resolveLinkTos: false));
}
public async Task <long?> GetLastEventNumberAsync(string streamName)
{
var lastEvent = await eventStoreConnection.ReadEventAsync(streamName, -1, false, CredentialsHelper.Default);
return(lastEvent?.Event?.OriginalEventNumber);
}
private static void ReadEvent(IEventStoreConnection connection)
{
EventReadResult result = connection.ReadEventAsync("test-stream", 0, false).Result;
if (result.Event.HasValue)
{
Console.WriteLine("id: " + result.Event.Value.Event.EventId);
string data = Encoding.UTF8.GetString(result.Event.Value.Event.Data);
Console.WriteLine("data: " + data);
string metadata = Encoding.UTF8.GetString(result.Event.Value.Event.Metadata);
Console.WriteLine("metadata: " + metadata);
}
}
public Task <EventReadResult> ReadEventFromStream(string streamName, long eventNumber, bool resolveLinkTos) => _client.ReadEventAsync(streamName, eventNumber, resolveLinkTos);
protected void ReadEvent(string streamId, string login, string password)
{
Connection.ReadEventAsync(streamId, -1, false,
login == null && password == null ? null : new UserCredentials(login, password))
.Wait();
}
protected Task ReadEvent(string streamId, string login, string password)
{
return(Connection.ReadEventAsync(streamId, -1, false,
login == null && password == null ? null : new UserCredentials(login, password)));
}
public async Task <HealthCheckResult> CheckHealthAsync(HealthCheckContext context, CancellationToken cancellationToken = default)
{
await connection.ReadEventAsync("test", 1, false);
return(HealthCheckResult.Healthy("Application must query data from EventStore."));
}
private async Task <SnapShotSearchSearch?> FindSnapshotEvent(string persistenceId, string streamName, IEventStoreConnection connection, SnapshotSelectionCriteria criteria)
{
if (SnapshotSelectionCriteria.Latest.Equals(criteria))
{
// Always just read last snapshot, theres no point trying to read old snapshots..
// Also here 'criteria.MaxSequenceNr' has no relationship to the position in the event stream, this was a BUG!
var latestSnapshot = await connection.ReadEventAsync(streamName, StreamPosition.End, false);
if (latestSnapshot.Status != EventReadStatus.Success)
{
_log.Debug("No snapshot found for: {0}", persistenceId);
return(null);
}
var @event = latestSnapshot.Event.Value.Event;
var representation = (SnapshotRepresentation)_serializer.FromBinary(@event.Data, typeof(SnapshotRepresentation));
return(new SnapShotSearchSearch {
snapshot = ToSelectedSnapshot(representation),
streamOffset = latestSnapshot.Event.Value.OriginalEventNumber,
});
}
else
{
var currentPosition = (long)StreamPosition.End;
while (true)
{
// Always just read last snapshot, theres no point trying to read old snapshots..
// Also here 'criteria.MaxSequenceNr' has no relationship to the position in the event stream, this was a BUG!
var latestSnapshot = await connection.ReadEventAsync(streamName, currentPosition, false);
if (latestSnapshot.Status != EventReadStatus.Success)
{
_log.Debug("No snapshot found for: {0}", persistenceId);
break;
}
else
{
_log.Debug("Found snapshot of {0}", persistenceId);
var @event = latestSnapshot.Event.Value.Event;
var representation = (SnapshotRepresentation)_serializer.FromBinary(@event.Data, typeof(SnapshotRepresentation));
var result = ToSelectedSnapshot(representation);
if (result.Metadata.SequenceNr < criteria.MinSequenceNr)
{
break;
}
if (criteria.MinTimestamp.HasValue)
{
if (result.Metadata.Timestamp < criteria.MinTimestamp.Value)
{
break;
}
}
if (result.Metadata.SequenceNr <= criteria.MaxSequenceNr && result.Metadata.Timestamp <= criteria.MaxTimeStamp)
{
return(new SnapShotSearchSearch
{
snapshot = ToSelectedSnapshot(representation),
streamOffset = currentPosition,
});
}
else
{
// Read the next event
currentPosition = latestSnapshot.Event.Value.OriginalEventNumber - 1L;
if (currentPosition < 1L)
{
break;
}
}
}
}
return(null);
}
}
