MassTransit Kafka Demo

Introduction

Demonstrates use of MassTransit Kafka rider to produce and consume messages, including support for multiple message types on a single topic.

Support for multiple event types per topic implemented via a custom Avro serializer. Note that a similar approach is needed when using the Confluent.Kafka libraries directly. See https://github.com/danmalcolm/confluent-kafka-dotnet/tree/multiple-message-types-on-topic.

Implementation Notes

Prerequisites

Development environment requires Docker support, e.g. Docker Desktop on windows and docker compose.

Execute the following from command prompt within solution directory to start Kafka infrastructure (use docker-compose if your version of docker does not support the compose command):

docker compose up -d

It should then be possible to run the MassTransitKafkaDemo project.

Generating Avro classes

Install the tool apache.avro.tools 1.10 or higher (Apache tool supports logical types in avsc files)

This can be installed with:

dotnet tool install --global Apache.Avro.Tools --version 1.10.2

Generate types:

avrogen -s TaskRequested.V1.avsc ..\;avrogen -s TaskStarted.V1.avsc ..\;avrogen -s TaskCompleted.V1.avsc ..\;

Browsing schema registry

Examples using Powershell.

All subjects:

Invoke-RestMethod -Uri http://localhost:8081/subjects

Latest version:

Invoke-RestMethod -Uri http://localhost:8081/subjects/MassTransitKafkaDemo.Messages.TaskRequested/versions/latest | Format-List