dotnet-kafka-client

Basic Consumer and Producer example by using Confluent's Kafka client for .Net

All you need is to install Confluent.Kafka from NuGet Package Manager.

• Basic Producer

        var conf = new ProducerConfig { BootstrapServers = "localhost:9092" };
  
        Action<DeliveryReport<Null, string>> handler = r =>
            Console.WriteLine(!r.Error.IsError
                ? $"Delivered message to {r.TopicPartitionOffset}"
                : $"Delivery Error: {r.Error.Reason}");
  
        using (var p = new ProducerBuilder<Null, string>(conf).Build())
        {
            for (int i = 0; i < 100; ++i)
            {  
                //Enter the name of the topic, and start producing 
                
                p.Produce("TEST_TOPIC", new Message<Null, string> { Value = "Test "+i.ToString() }, handler);
            }
  
            // wait for up to 10 seconds for any inflight messages to be delivered.
            p.Flush(TimeSpan.FromSeconds(10));
        }
  

• Basic Consumer

        var conf = new ConsumerConfig
        {
            GroupId = "test-consumer-group",
            BootstrapServers = "localhost:9092",
            // Note: The AutoOffsetReset property determines the start offset in the event
            // there are not yet any committed offsets for the consumer group for the
            // topic/partitions of interest. By default, offsets are committed
            // automatically, so in this example, consumption will only start from the
            // earliest message in the topic 'TEST_TOPIC' the first time you run the program.
            AutoOffsetReset = AutoOffsetReset.Earliest
        };
  
        using (var c = new ConsumerBuilder<Ignore, string>(conf).Build())
        {
            // Enter name of the topic to consume
            c.Subscribe("TEST_TOPIC");
  
            CancellationTokenSource cts = new CancellationTokenSource();
            Console.CancelKeyPress += (_, e) => {
                e.Cancel = true; // prevent the process from terminating.
                cts.Cancel();
            };
  
            try
            {
                while (true)
                {
                    try
                    {
                        var cr = c.Consume(cts.Token);
                        //Consuming Started
                        //Do the job
  
                        Console.WriteLine($"Consumed message '{cr.Value}' at: '{cr.TopicPartitionOffset}'.");
                    }
                    catch (ConsumeException e)
                    {
                        Console.WriteLine($"Error occured: {e.Error.Reason}");
                    }
                }
            }
            catch (OperationCanceledException)
            {
                // Ensure the consumer leaves the group cleanly and final offsets are committed.
                c.Close();
            }
  

Before running the project, make sure that ZooKeeper instance is up and running and Kafka server is started!