/// <summary>
/// Connect to server. Return <c>false</c> if subscribe fails
/// </summary>
/// <returns></returns>
public async Task <bool> SubscribeAsync()
{
if (_call == null)
{
_ = Task.Run(StartReceivingEvents);
}
var request = new SubscribeRequest
{
StartStop = true,
AccountName = AccountName
};
_logControl.LogMessage($"{_clientName} is subscribing to event {request.AccountName}");
while (_call == null)
{
await Task.Delay(10).ConfigureAwait(false);
}
try
{
await _call.RequestStream.WriteAsync(request);
}
catch (RpcException ex)
{
_logControl.LogMessage($"{ex.Message}\nRemember to use the StartServer button on FormServer");
_call = null;
_removeSubscription(AccountName);
return(false);
}
return(true);
}
private async void AccountOnSampleEvent(object sender, SampleEventArgs e)
{
try
{
_logControl.LogMessage($"Sending {e} to requester={_sampleEventKey}");
var args = e.ToSampleEventArgsMessage();
await _responseStream.WriteAsync(args);
}
catch (Exception ex)
{
// Eo graceful recovery when client has disappeared
_logControl.LogMessage($"Exception: {ex.Message}");
_removeAction(_sampleEventKey);
Dispose();
}
}
public override async Task Subscribe(IAsyncStreamReader <SubscribeRequest> requestStream, IServerStreamWriter <SampleEventArgsMessage> responseStream, ServerCallContext context)
{
var requesterHeader = context.RequestHeaders.FirstOrDefault(x => x.Key == Constants.Requester.ToLower()); // Must be lower case. Ugh!
var peer = context.Peer;
var requester = requesterHeader == null ? $"Anonymous@{peer}" : $"{requesterHeader.Value}@{peer}";
while (await requestStream.MoveNext())
{
var request = requestStream.Current;
var key = new SampleEventKey(request.AccountName, requester);
if (request.StartStop)
{
var writer = new AccountSampleEventWriter(key, responseStream, _logControl, RemoveWriter);
_eventWriters.TryAdd(key, writer);
OnAccountNameAdded(request.AccountName);
_logControl.LogMessage($"Added subscription to SampleEvents for {AccountNameAdded}");
}
else
{
RemoveWriter(key);
return;
}
}
}
