Kafka, dotnet and SASL_SSL

This is similar to my previous post, only now the question is, how do you connect to a Kafka server using dotnet and SASL_SSL? This is how:

// based on https://github.com/confluentinc/confluent-kafka-dotnet/blob/v1.0.0/examples/Producer/Program.cs

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

namespace Confluent.Kafka.Examples.ProducerExample
    public class Program
        public static async Task Main(string[] args)
            string topicName = "test-topic";

            var config = new ProducerConfig {
                BootstrapServers = "kafka-server.example.com:19094",
                SecurityProtocol = SecurityProtocol.SaslSsl,
                SslCaLocation = "ca-cert",
                SaslMechanism = SaslMechanism.Plain,
                SaslUsername = "USERNAME",
                SaslPassword = "PASSWORD",
                Acks = Acks.Leader,
                CompressionType = CompressionType.Lz4,

            using (var producer = new ProducerBuilder<string, string>(config).Build())
                for (int i = 0; i < 1000000; i++)
                    var message = $"Event {i}";

                        // Note: Awaiting the asynchronous produce request
                        // below prevents flow of execution from proceeding
                        // until the acknowledgement from the broker is
                        // received (at the expense of low throughput).

                        var deliveryReport = await producer.ProduceAsync(topicName, new Message<string, string> { Key = null, Value = message } );
                        // Console.WriteLine($"delivered to: {deliveryReport.TopicPartitionOffset}");

                        // Let's not await then
                        // producer.ProduceAsync(topicName, new Message<string, string> { Key = null, Value = message } );
                        // Console.WriteLine($"Event {i} sent.");
                    catch (ProduceException<string, string> e)
                        Console.WriteLine($"failed to deliver message: {e.Message} [{e.Error.Code}]");

                // producer.Flush(TimeSpan.FromSeconds(120));

                // Since we are producing synchronously, at this point there will be no messages
                // in-flight and no delivery reports waiting to be acknowledged, so there is no
                // need to call producer.Flush before disposing the producer.

Since I am a total .NET newbie, I usually docker run -it --rm microsoft/dotnet and experiment from there.

4 thoughts on “Kafka, dotnet and SASL_SSL

  1. do you have working example for SASL+SSL (with Kerberos) with dot net kafka client?

  2. I have not done it because among other things it requires you compile librdkafka on your own and I am too old for that :)

  3. I don’t find any dot net kafka client lib which support SASL+SSL with kerberos? do you know any?

    1. You have to compile librdkafka yourself to support Kerberos and SSL_SASL and then on top of that compile, again yourself, the dotnet version.

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