Hello,

I’m trying to implement a monitoring system where my element monitors multiple other elements (let’s call them Master-Slave), so I chose to use InterApp. I followed the InterApp documentation and did the following:

1. Created a NuGet solution which serves as the Message API.

public class GetChain : Message
{
public GetChain() : base()
{
}

public PolarizationType Type { get; set; }
}

public class GetChainResult : Message
{
public GetChainResult() : base()
{
}

public ChainState[] ActiveChains { get; set; }

public PolarizationType PolarizationType { get; set; }
}

2. Created the logic in my “Master” protocol which is sending the request message to one of the slaves with a timeout of 30 seconds. The message gets correctly processed in the Executor in the “Slave” protocol. I also made sure the ReturnAddress data is correct.

// Master protocol sending the message
var responses = command.Send(protocol.SLNet.RawConnection, ddaAgentId, ddaElementId, 9000000, new TimeSpan(0, 0, 30), knownTypes);

3. The Executor in the “Slave” protocol returns the Message with the correct Guid and sends it back like this:

foreach (var message in receivedCall.Messages)
{
if (message.TryExecute(protocol, protocol, msgToExecutor, out Message returnMessage))
{
protocol.Log($”QA{protocol.QActionID}|Execute successful”, LogType.Information, LogLevel.NoLogging);
}

if (returnMessage != null)
{
protocol.Log(“QA” + protocol.QActionID + “|Run|Sending return message with GUID ‘” + returnMessage.Guid + “‘.”, LogType.DebugInfo, LogLevel.NoLogging);

returnMessage.Send(
protocol.SLNet.RawConnection,
receivedCall.ReturnAddress.AgentId,
receivedCall.ReturnAddress.ElementId,
receivedCall.ReturnAddress.ParameterId,
knownTypes);
}
}

And the message contains the correct Guid:

2023/08/07 14:58:21.322|SLManagedScripting.exe|ManagedInterop|DBG|0|62|QA9000000|Run|Sending return message with GUID ‘9396cc0a-e5f2-4b7f-b5fe-3c8c9ff99924’.

4. The command.Send throws a TimeoutException:

2023/08/07 14:58:51.606|SLManagedScripting.exe|ManagedInterop|ERR|0|53|QA9000|9001|Run|Exception thrown:
System.TimeoutException: Timeout while waiting on responses: 9396cc0a-e5f2-4b7f-b5fe-3c8c9ff99924

I’ve logged the parameter 9000001, where the return message should come, and it contains the correct data, with the correct GUIDs; however, I can’t see the data in the responses parameter from step 2.

Am I doing something wrong? The documentation seems straightforward about sending a return message.