Getting a FabricElementAlreadyExistsException on ServiceRemotingMessageHeaders.AddHeader()

[wouterroos]

Hi,

I have the following implementation of IServiceRemotingClient to add a header to the IServiceRemotingRequestMessage instance:

public class SetOperationContextServiceRemotingClient : IServiceRemotingClient
{
    //other IServiceRemotingClient members ommitted for brevity

    public Task<IServiceRemotingResponseMessage> RequestResponseAsync(IServiceRemotingRequestMessage requestRequestMessage)
    {
        var message = //build message
        
        requestRequestMessage.GetHeader().AddHeader("MyMessageHeader", Encoding.ASCII.GetBytes(message));
        return InnerClient.RequestResponseAsync(requestRequestMessage);
    }
}    

This works perfectly in all our tests and local cluster but recently we occasionally get a FabricElementAlreadyExistsException which states: 'Header with name 'MyMessageHeader' already exists'. This issue seems to occur when the call to the service fails due to some reason so my guess is that a retry mechanism is at work here. Is this correct, and if so, should I implement IServiceRemotingClient.RequestResponseAsync() to be idempotent to prevent this issue?

Thanks!

[wouterroos]

Hi,

Could someone provide some feedback on this issue?

Thanks!