private async Task ReadEventStreamAsync(Func <IBinlogEvent, Task> handleEvent, CancellationToken cancellationToken = default)
{
var eventStreamReader = new EventStreamReader(_databaseProvider.Deserializer);
var channel = new EventStreamChannel(eventStreamReader, _channel.Stream, cancellationToken);
var timeout = _options.HeartbeatInterval.Add(TimeSpan.FromMilliseconds(TimeoutConstants.Delta));
while (!cancellationToken.IsCancellationRequested)
{
var packet = await channel.ReadPacketAsync(cancellationToken).WithTimeout(timeout, TimeoutConstants.Message);
if (packet is IBinlogEvent binlogEvent)
{
// We stop replication if client code throws an exception
// As a derived database may end up in an inconsistent state.
await handleEvent(binlogEvent);
// Commit replication state if there is no exception.
UpdateGtidPosition(binlogEvent);
UpdateBinlogPosition(binlogEvent);
}
else if (packet is ErrorPacket error)
{
throw new InvalidOperationException($"Event stream error. {error.ToString()}");
}
else if (packet is EndOfFilePacket && !_options.Blocking)
{
return;
}
else
{
throw new InvalidOperationException($"Event stream unexpected error.");
}
}
}
public async Task Test_LargeSplitPacket_Combined()
{
using var stream = new MemoryStream();
int lastPacketLength = 150;
var packetBody = CreateLargePacket(stream, PacketConstants.MaxBodyLength * 4 + lastPacketLength);
stream.Position = 0;
var channel = new EventStreamChannel(new TestEventStreamReader(), stream);
var packet = await channel.ReadPacketAsync();
Assert.IsType <TestPacket>(packet);
Assert.Equal(packetBody, ((TestPacket)packet).Body);
}
public async Task Test_PacketExactly16MbWithEmptyPacket_Combined()
{
using var stream = new MemoryStream();
var packetBody = CreateLargePacket(stream, PacketConstants.MaxBodyLength);
WriteHeader(stream, 1, 0); // empty packet
stream.Position = 0;
var channel = new EventStreamChannel(new TestEventStreamReader(), stream);
var packet = await channel.ReadPacketAsync();
Assert.IsType <TestPacket>(packet);
Assert.Equal(packetBody, ((TestPacket)packet).Body);
}
/// <summary>
/// Replicates binlog events from the server
/// </summary>
/// <param name="cancellationToken">Cancellation token</param>
/// <returns>Task completed when last event is read in non-blocking mode</returns>
public async IAsyncEnumerable <IBinlogEvent> Replicate([EnumeratorCancellation] CancellationToken cancellationToken = default)
{
await ConnectAsync(cancellationToken);
// Clear on reconnect
_gtid = null;
_transaction = false;
await AdjustStartingPosition(cancellationToken);
await SetMasterHeartbeat(cancellationToken);
await SetMasterBinlogChecksum(cancellationToken);
await _databaseProvider.DumpBinlogAsync(_channel, _options, cancellationToken);
var eventStreamReader = new EventStreamReader(_databaseProvider.Deserializer);
var channel = new EventStreamChannel(eventStreamReader, _channel.Stream);
var timeout = _options.HeartbeatInterval.Add(TimeSpan.FromMilliseconds(TimeoutConstants.Delta));
await foreach (var packet in channel.ReadPacketAsync(timeout, cancellationToken).WithCancellation(cancellationToken))
{
if (packet is IBinlogEvent binlogEvent)
{
// We stop replication if client code throws an exception
// As a derived database may end up in an inconsistent state.
yield return(binlogEvent);
// Commit replication state if there is no exception.
UpdateGtidPosition(binlogEvent);
UpdateBinlogPosition(binlogEvent);
}
else if (packet is EndOfFilePacket && !_options.Blocking)
{
yield break;
}
else if (packet is ErrorPacket error)
{
throw new InvalidOperationException($"Event stream error. {error.ToString()}");
}
else
{
throw new InvalidOperationException($"Event stream unexpected error.");
}
}
}
public async Task Test_PacketExactly16MbWithEmptyPacket_Combined()
{
using var stream = new MemoryStream();
var packetBody = CreateLargePacket(stream, PacketConstants.MaxBodyLength);
WriteHeader(stream, 1, 0); // empty packet
stream.Position = 0;
var channel = new EventStreamChannel(new TestEventStreamReader(), stream);
var packets = new List <IPacket>();
await foreach (var packet in channel.ReadPacketAsync(TimeSpan.FromSeconds(30)))
{
packets.Add(packet);
}
Assert.Equal(1, packets.Count);
Assert.IsType <TestPacket>(packets[0]);
Assert.Equal(packetBody, ((TestPacket)packets[0]).Body);
}
