private Func <CancellationToken, Task <string> > GetJsonData(PostgresqlStreamId streamId, int version)
=> async cancellationToken =>
{
using (var connection = await OpenConnection(cancellationToken))
using (var transaction = connection.BeginTransaction())
using (var command = BuildFunctionCommand(
_schema.ReadJsonData,
transaction,
Parameters.StreamId(streamId),
Parameters.Version(version)))
using (var reader = await command
.ExecuteReaderAsync(CommandBehavior.SequentialAccess, cancellationToken)
.NotOnCapturedContext())
{
if (!await reader.ReadAsync(cancellationToken).NotOnCapturedContext() || reader.IsDBNull(0))
{
return(null);
}
using (var textReader = reader.GetTextReader(0))
{
return(await textReader.ReadToEndAsync().NotOnCapturedContext());
}
}
};
private async Task DeleteStreamInternal(
PostgresqlStreamId streamId,
int expectedVersion,
IDbTransaction transaction,
CancellationToken cancellationToken)
{
using (var command = BuildFunctionCommand(
_schema.DeleteStream,
transaction,
Parameters.StreamId(streamId),
Parameters.ExpectedVersion(expectedVersion),
Parameters.CreatedUtc(_settings.GetUtcNow?.Invoke()),
Parameters.DeletionTrackingDisabled(_settings.DisableDeletionTracking),
_settings.DisableDeletionTracking ? Parameters.Empty() : Parameters.DeletedStreamId,
_settings.DisableDeletionTracking ? Parameters.Empty() : Parameters.DeletedStreamIdOriginal,
_settings.DisableDeletionTracking ? Parameters.Empty() : Parameters.DeletedStreamMessage(streamId)))
{
try
{
await command.ExecuteNonQueryAsync(cancellationToken).NotOnCapturedContext();
}
catch (PostgresException ex) when(ex.IsWrongExpectedVersion())
{
await transaction.RollbackAsync(cancellationToken).NotOnCapturedContext();
throw new WrongExpectedVersionException(
ErrorMessages.DeleteStreamFailedWrongExpectedVersion(streamId.IdOriginal, expectedVersion),
streamId.IdOriginal,
expectedVersion,
ex);
}
}
}
public StreamIdInfo(string idOriginal)
{
Ensure.That(idOriginal, nameof(idOriginal)).IsNotNullOrWhiteSpace();
PostgresqlStreamId = new PostgresqlStreamId(idOriginal);
MetadataPosgresqlStreamId = new PostgresqlStreamId("$$" + idOriginal);
}
private Func <CancellationToken, Task <string> > GetJsonData(PostgresqlStreamId streamId, int version)
=> async cancellationToken =>
{
using (var connection = await OpenConnection(cancellationToken))
using (var transaction = connection.BeginTransaction())
using (var command = BuildFunctionCommand(
_schema.ReadJsonData,
transaction,
Parameters.StreamId(streamId),
Parameters.Version(version)))
{
var jsonData = await command.ExecuteScalarAsync(cancellationToken).NotOnCapturedContext();
return(jsonData == DBNull.Value ? null : (string)jsonData);
}
};
private async Task <ReadStreamPage> ReadStreamInternal(
PostgresqlStreamId streamId,
int start,
int count,
ReadDirection direction,
bool prefetch,
ReadNextStreamPage readNext,
NpgsqlTransaction transaction,
CancellationToken cancellationToken)
{
// If the count is int.MaxValue, TSql will see it as a negative number.
// Users shouldn't be using int.MaxValue in the first place anyway.
count = count == int.MaxValue ? count - 1 : count;
// To read backwards from end, need to use int MaxValue
var streamVersion = start == StreamVersion.End ? int.MaxValue : start;
var messages = new List <(StreamMessage message, int?maxAge)>();
Func <List <StreamMessage>, int, int> getNextVersion;
if (direction == ReadDirection.Forward)
{
getNextVersion = (events, lastVersion) =>
{
if (events.Any())
{
return(events.Last().StreamVersion + 1);
}
return(lastVersion + 1);
};
}
else
{
getNextVersion = (events, lastVersion) =>
{
if (events.Any())
{
return(events.Last().StreamVersion - 1);
}
return(-1);
};
}
var refcursorSql = new StringBuilder();
using (var command = BuildFunctionCommand(
_schema.Read,
transaction,
Parameters.StreamId(streamId),
Parameters.Count(count + 1),
Parameters.Version(streamVersion),
Parameters.ReadDirection(direction),
Parameters.Prefetch(prefetch)))
using (var reader = await command
.ExecuteReaderAsync(CommandBehavior.SequentialAccess, cancellationToken)
.ConfigureAwait(false))
{
while (await reader.ReadAsync(cancellationToken).ConfigureAwait(false))
{
refcursorSql.AppendLine(Schema.FetchAll(reader.GetString(0)));
}
}
using (var command = new NpgsqlCommand(refcursorSql.ToString(), transaction.Connection, transaction))
using (var reader = await command
.ExecuteReaderAsync(CommandBehavior.SequentialAccess, cancellationToken)
.ConfigureAwait(false))
{
if (!reader.HasRows)
{
return(new ReadStreamPage(
streamId.IdOriginal,
PageReadStatus.StreamNotFound,
start,
-1,
-1,
-1,
direction,
true,
readNext));
}
if (messages.Count == count)
{
messages.Add(default);