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Building Reactive Java Applications with Spring Framework

If you’re a Java developer who uses the Spring ecosystem, you’ve probably seen the Spring Pet Clinic. In this workshop, we will walk you through a new reactive implementation of the Pet Clinic backend that uses Spring WebFlux and Apache Cassandra® (via DataStax Astra DB).

The cloud-native database-as-a-service built on Cassandra fits the highly concurrent, non-blocking nature of our reactive application. We’ll do all of our work in the cloud with Gitpod’s open-source, zero-install and collaborative development environment.

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Spring Transaction Debugging in Prod With Lightrun

Spring makes building a reliable application much easier thanks to its declarative transaction management. It also supports programmatic transaction management, but that’s not as common. In this article, I want to focus on the declarative transaction management angle, since it seems much harder to debug compared to the programmatic approach.

This is partially true. We can’t put a breakpoint on a transactional annotation. But I’m getting ahead of myself.

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Spring Boot: Nice and Easy [Video]

Ever looked for a comprehensive intro to Spring Boot that is fun and entertaining at the same time? Then have a look at this brand-new episode of the "Marco Codes" YouTube channel: Spring Boot - Nice & Easy.

In this video, we will build a tiny Google Photos-like clone with Spring Boot. Additionally, along the way, you'll learn plenty about Spring's Dependency Injection and MVC frameworks, Validation and File Handling, Spring Data and Databases, and you'll even deploy your application at the end. 

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Chaos Mesh + SkyWalking: Better Observability for Chaos Engineering

Chaos Mesh is an open-source cloud-native chaos engineering platform. You can use Chaos Mesh to conveniently inject failures and simulate abnormalities that might occur in reality, so you can identify potential problems in your system. Chaos Mesh also offers a Chaos Dashboard which allows you to monitor the status of a chaos experiment. However, this dashboard cannot let you observe how the failures in the experiment impact the service performance of applications. This hinders us from further testing our systems and finding potential problems. 

Apache SkyWalking is an open-source application performance monitor (APM), specially designed to monitor, track, and diagnose cloud-native, container-based distributed systems. It collects events that occur and then displays them on its dashboard, allowing you to observe directly the type and number of events that have occurred in your system and how different events impact the service performance. 

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Asynchronous API Calls: Spring Boot, Feign, and Spring @Async

The requirement was to hit an eternal web endpoint and fetch some data and apply some logic to it, but the external API was super slow and the response time grew linearly with the number of records fetched. This called for the need to parallelize the entire API call in chunks/pages and aggregate the data.

Our synchronous feign client:

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Delivering Your Code to the Cloud With JFrog Artifactory and GitHub Actions

Introduction

Artifactory and GitHub actions work great together to manage your deployments to the cloud. In this post, we’re showing an example that deploys an application to Microsoft Azure. This case involves an Azure web app, but the techniques we’re showing today could be used to deploy to any cloud service, virtual machines, or Kubernetes. Also, the application highlighted today is written in Java, but you could use any type of application code in the same way. I’m using Azure web apps because it has built-in CI/CD integration and it integrates easily with JFrog products, including Artifactory and X-Ray. The IDE I’m using is Visual Studio Code, an open-source, free text editor you can get at code.visualstudio.com. Our code is in a GitHub repo, and we're storing some of the dependency artifacts using Artifactory. Here’s a screenshot of the application:

It's a Spring Boot application that shows the Microsoft Developer Advocate mascot named Bit.  You can find the source code in this repo.