private async Task AppendToStreamExpectedVersionAny(
StreamIdInfo streamIdInfo,
int expectedVersion,
NewStreamEvent[] events,
CancellationToken cancellationToken)
{
var sqlDataRecords = CreateSqlDataRecords(events);
using (var connection = _createConnection())
{
await connection.OpenAsync(cancellationToken).NotOnCapturedContext();
using (var command = new SqlCommand(_scripts.AppendStreamExpectedVersionAny, connection))
{
command.Parameters.AddWithValue("streamId", streamIdInfo.Hash);
command.Parameters.AddWithValue("streamIdOriginal", streamIdInfo.Id);
var eventsParam = CreateNewEventsSqlParameter(sqlDataRecords);
command.Parameters.Add(eventsParam);
try
{
await command
.ExecuteNonQueryAsync(cancellationToken)
.NotOnCapturedContext();
}
catch (SqlException ex)
{
// Check for unique constraint violation on
// https://technet.microsoft.com/en-us/library/aa258747%28v=sql.80%29.aspx
if (ex.IsUniqueConstraintViolationOnIndex("IX_Events_StreamIdInternal_Id"))
{
// Idempotency handling. Check if the events have already been written.
var page = await ReadStreamInternal(
streamIdInfo.Id,
StreamVersion.Start,
events.Length,
ReadDirection.Forward,
connection,
cancellationToken)
.NotOnCapturedContext();
if (events.Length > page.Events.Length)
{
throw new WrongExpectedVersionException(
Messages.AppendFailedWrongExpectedVersion(streamIdInfo.Id, expectedVersion),
ex);
}
for (int i = 0; i < Math.Min(events.Length, page.Events.Length); i++)
{
if (events[i].EventId != page.Events[i].EventId)
{
throw new WrongExpectedVersionException(
Messages.AppendFailedWrongExpectedVersion(streamIdInfo.Id, expectedVersion),
ex);
}
}
return;
}
if (ex.IsUniqueConstraintViolation())
{
throw new WrongExpectedVersionException(
Messages.AppendFailedWrongExpectedVersion(streamIdInfo.Id, expectedVersion),
ex);
}
throw;
}
}
}
}
private async Task <StreamEventsPage> ReadStreamInternal(
string streamId,
int start,
int count,
ReadDirection direction,
SqlConnection connection,
CancellationToken cancellationToken)
{
var streamIdInfo = new StreamIdInfo(streamId);
var streamVersion = start == StreamVersion.End ? int.MaxValue : start;
// To read backwards from end, need to use int MaxValue
string commandText;
Func <List <StreamEvent>, int> getNextSequenceNumber;
if (direction == ReadDirection.Forward)
{
commandText = _scripts.ReadStreamForward;
getNextSequenceNumber = events => events.Last().StreamVersion + 1;
}
else
{
commandText = _scripts.ReadStreamBackward;
getNextSequenceNumber = events => events.Last().StreamVersion - 1;
}
using (var command = new SqlCommand(commandText, connection))
{
command.Parameters.AddWithValue("streamId", streamIdInfo.Hash);
command.Parameters.AddWithValue("count", count + 1); //Read extra row to see if at end or not
command.Parameters.AddWithValue("StreamVersion", streamVersion);
var streamEvents = new List <StreamEvent>();
var reader = await command.ExecuteReaderAsync(cancellationToken).NotOnCapturedContext();
await reader.ReadAsync(cancellationToken).NotOnCapturedContext();
var doesNotExist = reader.IsDBNull(0);
if (doesNotExist)
{
return(new StreamEventsPage(
streamId,
PageReadStatus.StreamNotFound,
start,
-1,
-1,
direction,
isEndOfStream: true));
}
// Read IsDeleted result set
var isDeleted = reader.GetBoolean(0);
if (isDeleted)
{
return(new StreamEventsPage(
streamId,
PageReadStatus.StreamDeleted,
0,
0,
0,
direction,
isEndOfStream: true));
}
// Read Events result set
await reader.NextResultAsync(cancellationToken).NotOnCapturedContext();
while (await reader.ReadAsync(cancellationToken).NotOnCapturedContext())
{
var streamVersion1 = reader.GetInt32(0);
var ordinal = reader.GetInt64(1);
var eventId = reader.GetGuid(2);
var created = reader.GetDateTime(3);
var type = reader.GetString(4);
var jsonData = reader.GetString(5);
var jsonMetadata = reader.GetString(6);
var streamEvent = new StreamEvent(
streamId,
eventId,
streamVersion1,
ordinal,
created,
type,
jsonData,
jsonMetadata);
streamEvents.Add(streamEvent);
}
// Read last event revision result set
await reader.NextResultAsync(cancellationToken).NotOnCapturedContext();
await reader.ReadAsync(cancellationToken).NotOnCapturedContext();
var lastStreamVersion = reader.GetInt32(0);
var isEnd = true;
if (streamEvents.Count == count + 1)
{
isEnd = false;
streamEvents.RemoveAt(count);
}
return(new StreamEventsPage(
streamId,
PageReadStatus.Success,
start,
getNextSequenceNumber(streamEvents),
lastStreamVersion,
direction,
isEnd,
streamEvents.ToArray()));
}
}
private async Task AppendToStreamExpectedVersion(
string streamId,
int expectedVersion,
NewStreamEvent[] events,
StreamIdInfo streamIdHash,
CancellationToken cancellationToken)
{
var sqlDataRecords = CreateSqlDataRecords(events);
using (var connection = _createConnection())
{
await connection.OpenAsync(cancellationToken).NotOnCapturedContext();
using (var command = new SqlCommand(_scripts.AppendStreamExpectedVersion, connection))
{
command.Parameters.AddWithValue("streamId", streamIdHash.Hash);
command.Parameters.AddWithValue("expectedStreamVersion", expectedVersion);
var eventsParam = CreateNewEventsSqlParameter(sqlDataRecords);
command.Parameters.Add(eventsParam);
try
{
await command
.ExecuteNonQueryAsync(cancellationToken)
.NotOnCapturedContext();
}
catch (SqlException ex)
{
if (ex.Errors.Count == 1)
{
var sqlError = ex.Errors[0];
if (sqlError.Message == "WrongExpectedVersion")
{
// Idempotency handling. Check if the events have already been written.
var page = await ReadStreamInternal(streamId,
expectedVersion + 1, // when reading for already written events, it's from the one after the expected
events.Length,
ReadDirection.Forward,
connection,
cancellationToken);
if (events.Length > page.Events.Length)
{
throw new WrongExpectedVersionException(
Messages.AppendFailedWrongExpectedVersion(streamId, expectedVersion),
ex);
}
for (int i = 0; i < Math.Min(events.Length, page.Events.Length); i++)
{
if (events[i].EventId != page.Events[i].EventId)
{
throw new WrongExpectedVersionException(
Messages.AppendFailedWrongExpectedVersion(streamId, expectedVersion),
ex);
}
}
return;
}
}
if (ex.IsUniqueConstraintViolation())
{
throw new WrongExpectedVersionException(
Messages.AppendFailedWrongExpectedVersion(streamId, expectedVersion),
ex);
}
throw;
}
}
}
}
