private EpochRecord WriteEpochRecordWithRetry(int epochNumber, Guid epochId, long lastEpochPosition,
Guid instanceId)
{
long pos = _writer.Checkpoint.ReadNonFlushed();
var epoch = new EpochRecord(pos, epochNumber, epochId, lastEpochPosition, DateTime.UtcNow, instanceId);
var rec = new SystemLogRecord(epoch.EpochPosition, epoch.TimeStamp, SystemRecordType.Epoch,
SystemRecordSerialization.Json, epoch.AsSerialized());
Log.Debug(
"=== Writing E{epochNumber}@{epochPosition}:{epochId:B} (previous epoch at {lastEpochPosition}). L={leaderId:B}.",
epochNumber, epoch.EpochPosition, epochId, lastEpochPosition, epoch.LeaderInstanceId);
if (!_writer.Write(rec, out pos))
{
epoch = new EpochRecord(pos, epochNumber, epochId, lastEpochPosition, DateTime.UtcNow, instanceId);
rec = new SystemLogRecord(epoch.EpochPosition, epoch.TimeStamp, SystemRecordType.Epoch,
SystemRecordSerialization.Json, epoch.AsSerialized());
if (!_writer.Write(rec, out pos))
{
throw new Exception($"Second write try failed at {epoch.EpochPosition}.");
}
}
_writer.Flush();
_bus.Publish(new SystemMessage.EpochWritten(epoch));
return(epoch);
}
public ISystemLogRecord CreateEpoch(EpochRecord epoch)
{
var result = new SystemLogRecord(
logPosition: epoch.EpochPosition,
timeStamp: epoch.TimeStamp,
systemRecordType: SystemRecordType.Epoch,
systemRecordSerialization: SystemRecordSerialization.Json,
data: epoch.AsSerialized());
return(result);
}
private EpochRecord WriteEpoch(int epochNumber, long lastPos, Guid instanceId)
{
long pos = _writer.Checkpoint.ReadNonFlushed();
var epoch = new EpochRecord(pos, epochNumber, Guid.NewGuid(), lastPos, DateTime.UtcNow, instanceId);
var rec = new SystemLogRecord(epoch.EpochPosition, epoch.TimeStamp, SystemRecordType.Epoch,
SystemRecordSerialization.Json, epoch.AsSerialized());
_writer.Write(rec, out _);
_writer.Flush();
return(epoch);
}
public override void When()
{
_epochId = Guid.NewGuid();
_epochNumber = 7;
var epoch = new EpochRecord(0, _epochNumber, _epochId, -1, DateTime.UtcNow, Guid.Empty);
var rec = new SystemLogRecord(epoch.EpochPosition, epoch.TimeStamp, SystemRecordType.Epoch,
SystemRecordSerialization.Json, epoch.AsSerialized());
Assert.True(Writer.Write(rec, out _));
Writer.Flush();
}
void WriteEpochInformationWithRetry(EpochRecord epoch)
{
if (!TryGetExpectedVersionForEpochInformation(epoch, out var expectedVersion))
{
expectedVersion = ExpectedVersion.NoStream;
}
var originalLogPosition = _writer.Checkpoint.ReadNonFlushed();
var epochInformation = LogRecord.Prepare(
factory: _recordFactory,
logPosition: originalLogPosition,
correlationId: Guid.NewGuid(),
eventId: Guid.NewGuid(),
transactionPos: originalLogPosition,
transactionOffset: 0,
eventStreamId: GetEpochInformationStream(),
expectedVersion: expectedVersion,
flags: PrepareFlags.SingleWrite | PrepareFlags.IsCommitted | PrepareFlags.IsJson,
eventType: GetEpochInformationEventType(),
data: epoch.AsSerialized(),
metadata: Empty.ByteArray);
if (_writer.Write(epochInformation, out var retryLogPosition))
{
return;
}
epochInformation = epochInformation.CopyForRetry(retryLogPosition, retryLogPosition);
if (_writer.Write(epochInformation, out _))
{
return;
}
throw new Exception(
string.Format("Second write try failed when first writing $epoch-information at {0}, then at {1}.",
originalLogPosition,
retryLogPosition));
}
private EpochRecord WriteEpochRecordWithRetry(int epochNumber, Guid epochId, long lastEpochPosition)
{
long pos = _writer.Checkpoint.ReadNonFlushed();
var epoch = new EpochRecord(pos, epochNumber, epochId, lastEpochPosition, DateTime.UtcNow);
var rec = new SystemLogRecord(epoch.EpochPosition, epoch.TimeStamp, SystemRecordType.Epoch, SystemRecordSerialization.Json, epoch.AsSerialized());
if (!_writer.Write(rec, out pos))
{
epoch = new EpochRecord(pos, epochNumber, epochId, lastEpochPosition, DateTime.UtcNow);
rec = new SystemLogRecord(epoch.EpochPosition, epoch.TimeStamp, SystemRecordType.Epoch, SystemRecordSerialization.Json, epoch.AsSerialized());
if (!_writer.Write(rec, out pos))
{
throw new Exception(string.Format("Second write try failed at {0}.", epoch.EpochPosition));
}
}
Log.Debug("=== Writing E{0}@{1}:{2:B} (previous epoch at {3}).", epochNumber, epoch.EpochPosition, epochId, lastEpochPosition);
return(epoch);
}