The Spring Blog

Engineering
Releases
News and Events

Stream Processing with Spring Cloud Stream and Apache Kafka Streams. Part 3 - Data deserialization and serialization

Part 1 - Programming Model
Part 2 - Programming Model Continued

Continuing on the previous two blog posts, in this series on writing stream processing applications with Spring Cloud Stream and Kafka Streams, now we will look at the details of how these applications handle deserialization on the inbound and serialization on the outbound.

All three major higher-level types in Kafka Streams - KStream<K,V>, KTable<K,V> and GlobalKTable<K,V> - work with a key and a value.

With Spring Cloud Stream Kafka Streams support, keys are always deserialized and serialized by using the native Serde mechanism. A Serde is a container object where it provides a deserializer and a serializer.

Read more...

Stream Processing with Spring Cloud Stream and Apache Kafka Streams. Part 2 - Programming Model Continued

On the heels of the previous blog in which we introduced the basic functional programming model for writing streaming applications with Spring Cloud Stream and Kafka Streams, in this part, we are going to further explore that programming model.

Let’s look at a few scenarios.

Scenario 1: Single input and output binding

If your application consumes data from a single input binding and produces data into an output binding, you can use Java’s Function interface to do that. Keep in mind that binding in this sense is not necessarily mapped to a single input Kafka topic, because topics could be multiplexed and attached to a single input binding (with comma-separated multiple topics configured on a single binding - see below for an example). On the outbound case, the binding maps to a single topic here.

Read more...

This Week in Spring - December 3, 2019

Hi, Spring fans! Can you believe - and I can’t, by the way - that we’re already in December 2019? The last month before the new year? The last month of this decade? It defies belief! I can’t even imagine how we got this far so quickly, but it’s great that we did. I started writing This Week in Spring in the first week of January 2011, so we’re fast approaching 9 years of This Week in Spring!

As I write this I am in Toronto, Canada, for the last stop on the SpringOne Tour train for 2019. I enjoyed giving a two-hour talk introducing all sorts of stuff in the wide world of Reactive Spring yesterday. Now, I am just biding my time, preparing for my departure to Australia later today. I am off to Australia for two stops on the YOW! conference circuit. I wholely look forward to seeing everyone there!

Read more...

Stream Processing with Spring Cloud Stream and Apache Kafka Streams. Part 1 - Programming Model

This is the first in a series of blog posts in which we will look at how stream processing applications are written using Spring Cloud Stream and Kafka Streams.

The Spring Cloud Stream Horsham release (3.0.0) introduces several changes to the way applications can leverage Apache Kafka using the binders for Kafka and Kafka Streams.
One of the major enhancements that this release brings to the table is first class support for writing apps by using a fully functional programming paradigm. This blog post gives an introduction to how this functional programming model can be used to develop stream processing applications with Spring Cloud Stream and Kafka Streams. In the subsequent blog posts in this series, we will look into more details.

Read more...

A Bootiful Podcast: Spring Tools lead Martin Lippert

Hi, Spring fans! In today’s episode Josh Long (@starbuxman) talks to Spring Tools lead Martin Lippert (@martinlippert) about his time at Pivotal, and on the Spring team, his work on Spring Tools, and his work on language servers that now serve as the foundational integration for Spring users using Microsoft’s Visual Studio Code, emacs and Atom, among other things.

Thanks, dear listener, and Happy Thanksgiving!

Read more...

This Week in Spring - November 26th, 2019

Hi, Spring fans! Welcome to yet another installment of This Week in Spring! This week, I’m in Tokyo, Japan, for the Pivotal Summit Japan event. I’ve regretfully had to miss the China and Korea events because of a famly emergency, so it’s nice to be able to make this, the last stop on the tour, before returning to California to celebrate Thanksgiving with the family.

And, on that note… it’s almost Thanksgiving in the US. Thanksgiving is a time for us in the US to reflect on that for which we’re thankful. I think I speak for the entire Spring team when I say that we are very grateful for you all, dear (worldwide) community! Happy Thanksgiving, all!

Read more...

Spring Cloud Task 2.2.1 GA is now available

We are pleased to announce that the Spring Cloud Task 2.2.1.RELEASE is now available on Github and the Pivotal download repository. Many thanks to all of those who contributed to this release.

What’s New?

The Spring Cloud Task 2.2.1.RELEASE is intended to be the version of the framework aligned with Spring Boot 2.2.x. Updates in this new version include:

  • Update all dependencies.
  • Micrometer support.
  • Updated documentation with improved format.
  • Task apps launched when using Spring Batch partitioning now have external-execution-id populated.
Read more...

Announcing the release of Spring Cloud Stream Horsham (3.0.0.RELEASE)

We are pleased to announce the release of the Spring Cloud Stream Horsham (3.0.0.RELEASE) release train which is available as part of Spring Cloud Hoxton.RELEASE (imminent) and builds on Spring Boot 2.2.x and Spring Cloud Function 3.0.0.RELEASE which was also just released.

Spring Cloud Stream Horsham.RELEASE modules are available for use in the Maven Central repository.

Quick highlights:

As mentioned in these posts (demystified and simplified, functional and reactive, stream and spring Integration and event routing) preceding this announcement, the core theme of this release is functions!.

Read more...

Announcing the release of Spring Cloud Function 3.0.0.RELEASE

We are pleased to announce the release of the Spring Cloud Function 3.0.0.RELEASE, which is available as part of Spring Cloud Hoxton.RELEASE (imminent) and builds on Spring Boot 2.2.x.

Spring Cloud Function 3.0.0.RELEASE modules are available for use in the Maven Central repository.

Quick highlights:

Transparent type conversion

This release introduces a refactored implementation of FunctionCatalog which amongst features such as function composition, support for reactive and non-reactive functions and more introduces transparent type conversion via MessageConverters provided by Spring Messaging.

Read more...