public async Task RegisterOnPremiseAsync(IOnPremiseConnectionContext onPremiseConnectionContext)
{
CheckDisposed();
_logger?.Debug("Registering link. link-id={LinkId}, connection-id={ConnectionId}, user-name={UserName}, role={Role} connector-version={ConnectorVersion}, connector-assembly-version={ConnectorAssemblyVersion}",
onPremiseConnectionContext.LinkId,
onPremiseConnectionContext.ConnectionId,
onPremiseConnectionContext.UserName,
onPremiseConnectionContext.Role,
onPremiseConnectionContext.ConnectorVersion,
onPremiseConnectionContext.ConnectorAssemblyVersion);
await _linkRepository.AddOrRenewActiveConnectionAsync(onPremiseConnectionContext.LinkId, OriginId, onPremiseConnectionContext.ConnectionId, onPremiseConnectionContext.ConnectorVersion, onPremiseConnectionContext.ConnectorAssemblyVersion).ConfigureAwait(false);
lock (_requestSubscriptions)
{
if (!_requestSubscriptions.ContainsKey(onPremiseConnectionContext.ConnectionId))
{
_requestSubscriptions[onPremiseConnectionContext.ConnectionId] = _messageDispatcher.OnRequestReceived(onPremiseConnectionContext.LinkId, onPremiseConnectionContext.ConnectionId, !onPremiseConnectionContext.SupportsAck)
.Subscribe(request => onPremiseConnectionContext.RequestAction(request, _cancellationToken));
onPremiseConnectionContext.IsActive = true;
}
}
_connectionContexts.TryAdd(onPremiseConnectionContext.ConnectionId, onPremiseConnectionContext);
if (onPremiseConnectionContext.SupportsConfiguration)
{
await ProvideLinkConfigurationAsync(onPremiseConnectionContext).ConfigureAwait(false);
}
}
private async Task ProvideLinkConfigurationAsync(IOnPremiseConnectionContext onPremiseConnectionContext)
{
try
{
var config = _linkRepository.GetLinkConfiguration(onPremiseConnectionContext.LinkId);
config.ApplyDefaults(_configuration);
var requestId = Guid.NewGuid().ToString();
_logger?.Debug("Sending configuration to OPC. connection-id={ConnectionId}, link-id={LinkId}, connector-version={ConnectorVersion}, link-configuration={@LinkConfiguration}, request-id={RequestId}", onPremiseConnectionContext.ConnectionId, onPremiseConnectionContext.LinkId, onPremiseConnectionContext.ConnectorVersion, config, requestId);
var request = new OnPremiseConnectorRequest()
{
HttpMethod = "CONFIG",
Url = String.Empty,
RequestStarted = DateTime.UtcNow,
OriginId = OriginId,
RequestId = requestId,
AcknowledgmentMode = AcknowledgmentMode.Auto,
Body = Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(config)),
};
// configs, like heartbeats, do not go through the message dispatcher but directly to the connection
await onPremiseConnectionContext.RequestAction(request, CancellationToken.None).ConfigureAwait(false);
}
catch (Exception ex)
{
_logger?.Error(ex, "An error happened while sending the link config to the connected OPC.");
}
}
private async Task MarkConnectionInactiveIfTimedOut(IOnPremiseConnectionContext connectionContext)
{
if (connectionContext.LastLocalActivity + _configuration.ActiveConnectionTimeout < DateTime.UtcNow)
{
await _backendCommunication.DeactivateOnPremiseConnectionAsync(connectionContext.ConnectionId);
}
}
private async Task SendHeartbeatAsync(IOnPremiseConnectionContext connectionContext, CancellationToken token)
{
if (connectionContext == null)
{
throw new ArgumentNullException(nameof(connectionContext));
}
if (connectionContext.NextHeartbeat > DateTime.UtcNow)
{
return;
}
connectionContext.NextHeartbeat = DateTime.UtcNow.Add(_heartbeatInterval);
try
{
_logger?.Verbose("Sending {PingMethod}. connection-id={ConnectionId}", connectionContext.SupportsHeartbeat ? "Heartbeat" : "Ping (as heartbeat)", connectionContext.ConnectionId);
var requestId = Guid.NewGuid().ToString();
var request = new OnPremiseConnectorRequest()
{
HttpMethod = connectionContext.SupportsHeartbeat ? "HEARTBEAT" : "PING",
Url = String.Empty,
RequestStarted = DateTime.UtcNow,
OriginId = _backendCommunication.OriginId,
RequestId = requestId,
AcknowledgmentMode = AcknowledgmentMode.Auto,
HttpHeaders = connectionContext.SupportsConfiguration ? null : new Dictionary <string, string> {
["X-TTRELAY-HEARTBEATINTERVAL"] = _heartbeatInterval.TotalSeconds.ToString(CultureInfo.InvariantCulture)
},
};
// wait for the response of the Heartbeat / Ping
var task = _backendCommunication.GetResponseAsync(requestId, _configuration.ActiveConnectionTimeout);
// heartbeats do NOT go through the message dispatcher as we want to heartbeat the connections directly
await connectionContext.RequestAction(request, token).ConfigureAwait(false);
var response = await task.ConfigureAwait(false);
if (response != null)
{
await _backendCommunication.RenewLastActivityAsync(connectionContext.ConnectionId).ConfigureAwait(false);
}
}
catch (Exception ex)
{
_logger?.Error(ex, "Error during sending heartbeat to a client. link-id={LinkId}, connection-id={ConnectionId}, connector-version={ConnectorVersion}", connectionContext.LinkId, connectionContext.ConnectionId, connectionContext.ConnectorVersion);
}
}
