Kafka producer in C# as Windows Service

Question

I created a Kafka producer, using Confluent library, as a console app that ran as a scheduled task to submit some error records to Kafka broker periodically. Worked fine.

I have to convert this to run as a Windows Service and I am running into some issues dealing with asynch nature of the call, using "await".

program.cs contains the basic code:

static void Main()
{
    /* Uncomment for debugging */
    //Debugger.Launch();

    ServiceBase[] ServicesToRun;
    ServicesToRun = new ServiceBase[]
    {
        new Kafka_Producer()
    };
    ServiceBase.Run(ServicesToRun);
}

File that contains service APIs:

public Kafka_Producer()
{
    InitializeComponent();
}

protected override void OnStart(string[] args)
{
    // Some initialization, setting global variables
    ...
    producer = new Producer(sBootstrapServer);

    // This line shows message: "Because this call is not awaited, execution of the current method continues before the call is completed. Consider applying the await operator to the result of the call"
    CheckDB();   

    // Set up a timer that triggers periodically.
    timer = new System.Timers.Timer();
    timer.Interval = iRunInterval;
    timer.Elapsed += new ElapsedEventHandler(this.OnTimer);
    timer.Start();
}

protected async Task CheckDB()
{
    List<string> lsJsonResult = ApplicationException.GetErrorsJSON();
    await producer.SendErrorData(sTopicName, lsJsonResult);
}

And SendErrorData is sending data to Kafka:

public async Task SendErrorData(string topicName, List<string> jsonResult)
{
    string logMessage = string.Empty;

    using (var producer = new ProducerBuilder<Null, string>(_producerConfig)
        .SetValueSerializer(Serializers.Utf8)
        .SetLogHandler((_, message) => LogWriter.LogWrite($"Facility: {message.Facility}-{message.Level} Message: {message.Message}"))
        .SetErrorHandler((_, e) => LogWriter.LogWrite($"Error: {e.Reason}. Is Fatal: {e.IsFatal}"))
        .Build())
        try
        {                    
            foreach(string sJsonErrData in jsonResult)
            {
                dynamic results = JsonConvert.DeserializeObject<dynamic>(sJsonErrData);
                int id = results.uniqueId;
                    
                var deliveryReport = await producer.ProduceAsync(topicName,
                    new Message<Null, string>
                    {
                        Value = sJsonErrData
                    });
                ....
            }
        }
        catch()
        {}
    }
         

What am I doing wrong?

Answer 1

You can try this, this will create another task and will wait kafka to produce your message in separate task

_ = Task.Run(async () => await CheckDB());