Posts Tagged ‘apachekafka’

Using Xbox to get started with Kafka Connect & Kafka Streams

Wednesday, May 17th, 2023

It’s easy for developers who aren’t immersed in all-things-Kafka to assume that “Apache Kafka” just means an event backbone: something that hosts topics (and perhaps the client libraries to produce and consume messages using those topics). But Kafka is more than that. It is an ecosystem of tools that enables a complete event-streaming application.

That was the premise of this talk, recorded at Devoxx UK, which I gave to a room of Java developers. I introduced them to two other bits of Kafka: Kafka Connect (for getting data in and out of Kafka topics from external systems) and Kafka Streams (for developing stream processing applications).

Because they were Java developers, I thought the best way to give them a flavour of these tools was to show them the APIs, and walk through an example solution made using the APIs.

The example solution used Kafka tools to process data from Xbox – mostly because I’m a gamer and it made for a fun, if silly, demo.

recording of the talk at


Using Apache Kafka with IBM MQ using Kafka Connect

Thursday, April 20th, 2023

A recording of a demo walkthrough I did about using the Kafka Connect MQ connectors to flow messages between IBM MQ and Apache Kafka.

A few weeks ago, I presented a session at TechCon about IBM MQ and Apache Kafka with David Ware. I spent most of my time running through how to use Kafka Connect with IBM MQ, with a few demos showing different ways to setup and run the kafka-connect-mq-source Connector.

My demos start at around 20 minutes in, but you should listen to David give the context first!

Using client quotas with IBM Event Streams

Sunday, February 26th, 2023

In this post, I want to highlight a feature that I often see under-used in IBM Event Streams, and show how you can easily give it a try.

Kafka can enforce quotas to limit the impact that client applications can have on your cluster. To quote the Kafka documentation:

It is possible for producers and consumers to produce/consume very high volumes of data or generate requests at a very high rate and thus monopolize broker resources, cause network saturation and generally DOS other clients and the brokers themselves.

Having quotas protects against these issues and is all the more important in large multi-tenant clusters where a small set of badly behaved clients can degrade user experience for the well behaved ones.

In fact, when running Kafka as a service this even makes it possible to enforce API limits according to an agreed upon contract.


Running IBM Event Streams on a laptop (sort of)

Friday, December 23rd, 2022

How to run a tiny local Kafka cluster using IBM Event Streams images

For local development on Kafka projects, I always run the public open source builds of ZooKeeper and Kafka as Java processes directly on my laptop (similar to steps described in the Apache Kafka Quickstart).

But for a project this week, I needed to verify something with the distribution of Kafka that comes with IBM Event Streams.

I used a simple Docker Compose setup for this. I’ll use this post to share how I did it.


Xbox LIVE events for Kafka

Monday, December 19th, 2022

I’ve made a Kafka Connect source connector for sending “real-time” events from Xbox LIVE to Kafka topics.

Quick primer if you’re not a gamer or don’t know what I’m talking about!
The Xbox platform comes with a social aspect: details about games you play and the achievements you earn playing them, are shared with your friends on the Xbox LIVE service. That is the source of data I’m using here.

Create an API key for your Xbox LIVE account, and run the Connector with it, and it will start producing two streams of events to your Kafka cluster:

Screenshot from Event Streams, but as a Kafka Connect connector, you could use any flavour of Kafka, including Apache Kafka.

Events when one of your friends earns an achievement.

Events when your friends start playing a game, or go online/offline.

Details about the attributes of each of these events can be found in the Connector README, but here are a few screenshots to give you an idea.

An example message on the ACHIEVEMENTS topic.


Setting up the Event Streams UI for developer-only use

Friday, December 9th, 2022

A quick tip for how to give a developer access to the IBM Event Streams UI only for the Kafka topics used by their application, and not everything else.

Imagine I’m a Kafka cluster admin. I’m running a cluster with a variety of topics on it.

Only viewing their own topics

One of my developers is responsible for the flight tracking app, and wants to use the Event Streams UI. But I don’t want them to be able to access the other sensitive topics for other applications.

I can create them their own login for the UI, that only lets them see their own topics.

The permissions I want to give them are:

- operation: Read
    name: FLIGHT.
    patternType: prefix
    type: topic

(Remember, managing my Kafka cluster through Kubernetes resources is a good fit with a CI/CD workflow.)


Using IBM DataStage to process JSON events on Apache Kafka topics

Monday, November 28th, 2022

In this post, I share a step-by-step guide for how to use IBM DataStage to merge JSON messages from multiple different Apache Kafka topics, into a single joined-up stream of events.



Setting up trusted SSL for IBM Event Streams

Thursday, October 27th, 2022

A quick how-to for setting up Event Streams with trusted certificates when running a development project.


You’re working on a project using IBM Event Streams. It’s just a development project, so you’re not using an SSL certificate signed by your real, trusted, corporate signer.

Everything works, but…

You get errors like these every time you access the web tooling – which you have to click through.

And you get errors like these from your Kafka client applications – which you have to configure with a custom truststore to avoid (although, if you do need to do that, I have a guide to help!)

[2021-06-27 23:19:06,048] ERROR [Consumer clientId=consumer-dalegrp-1, groupId=dalegrp] Connection to node -1 ( failed authentication due to: SSL handshake failed (org.apache.kafka.clients.NetworkClient)
[2021-06-27 23:19:06,049] WARN [Consumer clientId=consumer-dalegrp-1, groupId=dalegrp] Bootstrap broker (id: -1 rack: null) disconnected (org.apache.kafka.clients.NetworkClient)
[2021-06-27 23:19:06,069] ERROR Error processing message, terminating consumer process:  ($)
org.apache.kafka.common.errors.SslAuthenticationException: SSL handshake failed
Caused by: PKIX path building failed: unable to find valid certification path to requested target
	at java.base/
	at java.base/
	at java.base/
	at java.base/
	at java.base/$T13CertificateConsumer.checkServerCerts(
	at java.base/$T13CertificateConsumer.onConsumeCertificate(
	at java.base/$T13CertificateConsumer.consume(
	at java.base/
	at java.base/
	at java.base/$DelegatedTask$
	at java.base/$DelegatedTask$
	at java.base/
	at java.base/$