public Task <bool> MessageReceived(ProtocolMessage protocolMessage, RealtimeState state)
{
if (protocolMessage.Channel.IsEmpty())
{
return(Task.FromResult(false));
}
var channel = _channels.Exists(protocolMessage.Channel) ? GetChannel(protocolMessage.Channel) : null;
if (channel == null)
{
Logger.Warning($"Message received {protocolMessage} for a channel that does not exist {protocolMessage.Channel}");
return(Task.FromResult(false));
}
switch (protocolMessage.Action)
{
case ProtocolMessage.MessageAction.Error:
channel.SetChannelState(ChannelState.Failed, protocolMessage);
break;
case ProtocolMessage.MessageAction.Attached:
channel.Properties.AttachSerial = protocolMessage.ChannelSerial;
if (protocolMessage.Flags.HasValue)
{
var modes = new ChannelModes(((ProtocolMessage.Flag)protocolMessage.Flags.Value).FromFlag());
channel.Modes = new ReadOnlyChannelModes(modes.ToList());
}
if (protocolMessage.Params != null)
{
channel.Params = new ReadOnlyChannelParams(protocolMessage.Params);
}
if (channel.State == ChannelState.Attached)
{
// RTL12
if (!protocolMessage.HasFlag(ProtocolMessage.Flag.Resumed))
{
channel.Presence.ChannelAttached(protocolMessage);
channel.EmitUpdate(protocolMessage.Error, false, protocolMessage);
}
}
else
{
channel.SetChannelState(ChannelState.Attached, protocolMessage);
}
break;
case ProtocolMessage.MessageAction.Detach:
case ProtocolMessage.MessageAction.Detached:
if (channel.State != ChannelState.Detached)
{
channel.SetChannelState(ChannelState.Detached, protocolMessage);
}
break;
case ProtocolMessage.MessageAction.Message:
if (channel.State == ChannelState.Attaching)
{
Logger.Warning(
$"Channel #{channel.Name} is currently in Attaching state. Messages received in this state are ignored. Ignoring ${protocolMessage.Messages?.Length ?? 0} messages");
return(TaskConstants.BooleanTrue);
}
if (ValidateIfDeltaItHasCorrectPreviousMessageId(protocolMessage, channel.LastSuccessfulMessageIds) == false)
{
var message =
"Delta message decode failure. Previous message id does not equal expected message id.";
var reason = new ErrorInfo(message, ErrorCodes.VcDiffDecodeError);
channel.StartDecodeFailureRecovery(reason);
return(TaskConstants.BooleanTrue);
}
var result = _messageHandler.DecodeMessages(
protocolMessage,
protocolMessage.Messages,
channel.MessageDecodingContext);
if (result.IsFailure)
{
Logger.Error($"{channel.Name} - failed to decode message. ErrorCode: {result.Error.Code}, Message: {result.Error.Message}");
if (result.Error is VcDiffErrorInfo)
{
channel.StartDecodeFailureRecovery(result.Error);
// Break any further message processing
return(TaskConstants.BooleanTrue);
}
}
channel.LastSuccessfulMessageIds = LastMessageIds.Create(protocolMessage);
foreach (var msg in protocolMessage.Messages)
{
channel.OnMessage(msg);
}
break;
case ProtocolMessage.MessageAction.Presence:
case ProtocolMessage.MessageAction.Sync:
var presenceDecodeResult = _messageHandler.DecodeMessages(
protocolMessage,
protocolMessage.Presence,
channel.Options);
if (presenceDecodeResult.IsFailure)
{
Logger.Error($"{channel.Name} - failed to decode presence message. ErrorCode: {presenceDecodeResult.Error.Code}, Message: {presenceDecodeResult.Error.Message}");
channel.OnError(presenceDecodeResult.Error);
}
string syncSerial = protocolMessage.Action == ProtocolMessage.MessageAction.Sync
? protocolMessage.ChannelSerial
: null;
channel.Presence.OnPresence(protocolMessage.Presence, syncSerial);
break;
}
return(Task.FromResult(true));
}
private bool ValidateIfDeltaItHasCorrectPreviousMessageId(ProtocolMessage protocolMessage, LastMessageIds channelSuccessfulMessageIds)
{
if (protocolMessage.Messages == null || protocolMessage.Messages.Length == 0)
{
return(true);
}
var firstMessage = protocolMessage.Messages.First();
var deltaFrom = firstMessage.Extras?.Delta?.From;
if (deltaFrom != null && deltaFrom.EqualsTo(channelSuccessfulMessageIds.LastMessageId) == false)
{
Logger.Warning($"Delta message decode failure. Previous message id does not equal expected message id. PreviousMessageId: {channelSuccessfulMessageIds.LastMessageId}. ExpectedMessageId: {deltaFrom}");
return(false);
}
return(true);
}