A Java geek

Server-Side Rendering with Spring Boot

Understanding the shared steps in the project setup is crucial before delving into the specifics of each client-augmenting technology. My requirements from the last post where quite straightforward: I’ll assume the viewpoint of a backend developerNo front-end build step: no TypeScript, no minification, etc.All dependencies are managed from the backend app, i.e., Maven It’s important to note that the technology I’ll be detailing, except Vaadin, follows a similar approach.

Development

A short history of AJAX and SSR

My journey in programming began over two decades ago, a time when JavaScript was a far cry from its current state, and developers were primarily focused on Microsoft Internet Explorer. One of my proudest achievements back then was writing a few lines of code that allowed users to add and remove table rows entirely on the client side. We called it DHTML. Many developers today have forgotten about it—or never knew it existed.

Technical

DRY your Apache APISIX config

DRY is an important principle in software development. This post will show you how to apply it to Apache APISIX configuration. The DRY principle 'Don’t repeat yourself' (DRY) is a principle of software development aimed at reducing repetition of information which is likely to change, replacing it with abstractions that are less likely to change, or using data normalization which avoids redundancy in the first place.

Technical

When (not) to write an Apache APISIX plugin

When I introduce Apache APISIX in my talks, I mention the massive number of existing plugins, and that each of them implements a specific feature. One of the key features of Apache APISIX is its flexibility. If a feature is missing, you can create your own plugin in Lua or a language compiled into Wasm, showcasing the platform’s adaptability to your specific needs.

Development

Kotlin Coroutines and OpenTelemetry tracing

I recently compared three OpenTelemetry approaches on the JVM: Java Agent v1, v2, and Micrometer. I used Kotlin and coroutines without overthinking. I received interesting feedback on the usage of @WithSpan with coroutines: Nice one..by the way to instrument the coroutine context properly, don't we need "opentelemetry-extension-kotlin" also? Without that, spans are not recorded properly for suspend functions (https://t.co/DSgJklnllD) pic.twitter.

Programming

Default map value

In this post, I’ll explain how to provide a default value when querying an absent key in a hash map in different programming languages. Java Let’s start with Java, my first professional programming language. In older versions, retrieving a value from a map required using the get() method: Map map = new HashMap(); (1) Object value = map.

Development

OpenTelemetry Tracing on Spring Boot, Java Agent vs. Micrometer Tracing

My demo of OpenTelemetry Tracing features two Spring Boot components. One uses the Java agent, and I noticed a different behavior when I recently upgraded it from v1.x to v2.x. In the other one, I’m using Micrometer Tracing because I compile to GraalVM native, and it can’t process Java agents. I want to compare these three different ways in this post: Java agent v1, Java agent v2, and Micrometer Tracing.

Technical

Free tier API with Apache APISIX

Lots of service providers offer a free tier of their service. The idea is to let you kick their service’s tires freely. If you need to go above the free tier at any point, you’ll likely stay on the service and pay. In this day and age, most services are online and accessible via an API. Today, we will implement a free tier with Apache APISIX. A naive approach I implemented a free tier in my post Evolving your RESTful APIs, a step-by-step approach, albeit in a very naive way.

Technical

Differentiating rate limits in Apache APISIX

In my talk Evolving your APIs, I mention that an API Gateways is a Reverse Proxy 'on steroids'. One key difference between the former and the latter is that the API Gateway is not unfriendly to business logic. The poster child is rate-limiting. Rate-limiting is an age-old Reverse Proxy feature focused on protecting against DDoS attacks. It treats all clients the same and is purely technical.

Nicolas Fränkel's blog