Reactive programming is about messages, futures, events, channels and streams

In this blog post I want to point out the topic of the open sourced Reactive Cloud Native Starter example with Java backend Microservices and a Vue.js frontend web application. The gif below shows the example application. The application simply displays Articles and Authors information on a web page. You also see the creation of Articles with cURL commands in a terminal session and the UI is updated automatically.
(the gif is from the Cloud Native Starter project)

reactive demo
That example was mainly developed by Niklas Heidloff. He wrote a lot of very useful blog posts like Development of Reactive Applications with Quarkus related to that topic.

In this blog post I show, what could be useful to know, when you start with this Cloud Native Starter example for reactive programming to create and consume reactive RESTful APIs in an asynchronous way. I will also give a brief overview of the steps to create an article in the example application.

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How to create a new realm with the Keycloak REST API?

In this blog post I want to show, how to create a new realm with Keycloak REST API , because later I want to automate the Keycloak realm creation for a workshop using curl in a bash script.

The reason of that blog post is, that the information in the REST API documentation wasn’t detailed enough for me. The image shows what I found first in the Keycloak REST API documentation .

keycloak-create-realm-01

In common it’s very simple to use the Keycloak REST API. For more details see in my blog post Getting started to secure a simple Java Microservice with Keycloak, MicroProfile and OpenLiberty.

First you need a bearer authorization token for an administration user and with that token you create a new realm using the realm json exported before.

Here is what I found:

I used POSTMAN to check it out. These are the steps I did in POSTMAN.

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