A Java geek

The Vary HTTP header

I try to constantly deepen my knowledge of HTTP and REST. Recently, I stumbled upon the list of all registered HTTP Headers. This post is dedicated to the Vary HTTP Header. The problem Two years ago, I wrote about web resource caching server-side. The idea is to set up a component between the client and the upstream to cache previously computed results to avoid overloading the latter. Depending on your infrastructure and requirements, this component can be a reverse proxy or an API Gateway.

Development

Five ways to pass parameters to Apache APISIX

I recently read 6 Ways To Pass Parameters to Spring REST API. Though the title is a bit misleading, as it’s unrelated to REST, it does an excellent job listing all ways to send parameters to a Spring application. I want to do the same for Apache APISIX; it’s beneficial when you write a custom plugin. General setup The general setup uses Docker Compose and static configuration. I’ll have one plugin per way to pass parameters. docker-compose.

Development

The try block in Rust

I wrote previously about libs for error management in Rust. This week, I want to write about the try block, an experimental feature. The limit of the ? operator Please check the above article for a complete refresher on error management in general and the ? operator in particular. In short, ? allows to hook into a function call that returns a Result: If the Result contains a value, it continues normallyIf it contains an error, it short-circuits and returns the Result to the calling function.

Development

Dissolving Design Patterns In Design Elements

The book Design Patterns: Elements of Reusable Object-Oriented Software was one of the texts that changed how we think about software design.

Development

Implementing the Idempotency-Key specification on Apache APISIX

Last week, I wrote an analysis of the IETF Idempotency-Key specification. The specification aims to avoid duplicated requests. In short, the idea is for the client to send a unique key along with the request: If the server doesn’t know the key, it proceeds as usual and then stores the responseIf the server knows the key, it short-circuits any further processing and immediately returns the stored response This post shows how to implement it with Apache APISIX.

Development

Fixing duplicate API requests

The first rule of distributed systems is 'Don’t distribute your system'. Designing distributed systems right is infamously hard for multiple reasons. The idempotency concept For example, a call to a function can succeed or fail in non-distributed systems. Once you move the called function to a remote component, a third option appears: you call the remote function but get no response from the component.

Miscellaneous

Apache APISIX North America Tour

Once in a while, I write non-technical blog posts when I’ve something worth sharing. Today, I’d like to write about my North America 'Tour' across several conferences and user groups. The first leg of my journey started in Oakland, California, with Developer Week. Developer Week is an established conference with different editions in several locations and online during the year.

Development

The pitfall of implicit returns

Implicit returns are a feature in some languages. They have recently bitten me, so here’s my opinion. Statements, expressions, and returns Before diving into implicit returns, we must explain two programming concepts influencing them. A lot of literature is available on the subject, so I’ll paraphrase one of the existing definitions: An expression usually refers to a piece of code that can be evaluated to a value.

Technical

Using my new Raspberry Pi to run an existing GitHub Action

Recently, I mentioned how I refactored the script that kept my GitHub profile up-to-date. Since Geecon Prague, I’m also a happy owner of a Raspberry Pi: Guess what I won @GeeCON Prague? 😎 pic.twitter.com/b9dARUhfMd— Nicolas Fränkel 🇪🇺🇺🇦🇬🇪 (@nicolas_frankel) October 20, 2023 Though the current setup works flawlessly - and is free, I wanted to experiment with self-hosted runners. Here are my findings.

Nicolas Fränkel's blog