Producer.Dispose does not return after awaiting ProduceAsync

Description

In the code below the execution stops when leaving the using block. When pausing in Visual Studio the debugger reports two deadlocked tasks.

We derived the example below from the SimpleProducer example. We did not expect any significant difference in behavior, with reference to the producer documentation

How to reproduce

• Create a producer in an using block.
• Await call to ProduceAsync
• Leave using block

using System;
using System.Collections.Generic;
using System.Text;
using System.Threading.Tasks;
using Confluent.Kafka;
using Confluent.Kafka.Serialization;

namespace ResourceTest
{
    internal class Program
    {
        private static void Main(string[] args)
        {
            const string brokerList = "<broker-url>";
            const string topicName = "topic";

            var config = new Dictionary<string, object>
            {
                {"bootstrap.servers", brokerList}
            };

            PublishWithBlockingDispose(config, topicName).Wait();
        }

        private static async Task PublishWithBlockingDispose(Dictionary<string, object> config, string topicName)
        {
            using (var producer = new Producer<Null, string>(config, null, new StringSerializer(Encoding.UTF8)))
            {
                var deliveryReport =
                    await producer.ProduceAsync(topicName, null, "samplePayload").ConfigureAwait(false);
                Console.WriteLine($"Partition: {deliveryReport.Partition}, Offset: {deliveryReport.Offset}");
            }

            Console.WriteLine("Unreachable code");
        }
    }
}

Checklist

Confluent.Kafka nuget version: 0.11.2 Apache Kafka version: 0.11.0 Client configuration: See code example Operating system: Windows 10

[ig2r]

@scharrenberg we’re impacted by this issue also, but managed to work around it by having await Task.Yield() immediately after the call to ProduceAsync(...), as suggested initially in #92.

[mhowlett]

yes, I checked this and it’s resolved.