A naive credit card number validator

By LiBePosted on Tuesday 31 December 2019Tuesday 31 December 2019Cat G33k, ProgrammesLeave a comment

Of course, validating a credit card is not something we can do in a browser. If we did, we could get valid card numbers that don't match any account. The purpose of this post is then not to validate the card with the issuer, but to help the user to make sure that he did… Read More »

Ship modules without moment.js

By LiBePosted on Saturday 30 November 2019Saturday 30 November 2019Cat G33k, ProgrammesLeave a comment

Moment.js is a great and comprehensive library to use date, times, and formatting. Why should we use it ? Because the Date interface in javascript is lacking of flexibility. It also permits to to translate a moment in a any locale and language. Why should not we use it ? 232 kB (or 66 kB… Read More »

GraphQL in Kotlin : how to register generic scalars without sweating

By LiBePosted on Thursday 31 October 2019Thursday 31 October 2019Cat G33k, ProgrammesLeave a comment

If you are working like I do, you certainly are wrapping the smallest pieces of data to ensure they follow strict validation rules.And you are likely to wrap the small field values in wrapping type, for these reasons : - your IDE will tell you that you are manipulating an EmailAddress, an IPAddressV6 or a… Read More »

The no-breaking-change API

By LiBePosted on Monday 30 September 2019Monday 30 September 2019Cat G33k, ProgrammesLeave a comment

Ever thought of changing the API contract without having to ask for any upgrade ? Without waiting for all the consumers to adapt their client ? There is one technique that allow you to build backward compatible contracts, and it does not need versioning nor any deprecation strategy. What is it ? Just make good… Read More »

Quick JAXB codec (deserialize + serialize)

By LiBePosted on Saturday 31 August 2019Saturday 31 August 2019Cat G33k, ProgrammesLeave a comment

I never liked JAXB because it messes with the concept of tolerant API. It sometimes is very strict when it validates the user inputs, no matter if the problem is recoverable or not. I wrote several months ago a mapper that is able to deserialize a xml text into a recursive Map of xml elements.… Read More »

Coroutines in Spring API : give me !

By LiBePosted on Wednesday 31 July 2019Wednesday 31 July 2019Cat G33k, ProgrammesLeave a comment

Coroutines are a sharply increasing practice among Android developers, but it is seems quite limited to the Android ecosystem, even though the original intent of them is to create an agnostic framework to implement asynchronous and cheap concurrency programs. There already is a framework that can help combine together coroutines and spring mvc : https://github.com/konrad-kaminski/spring-kotlin-coroutine… Read More »

Routing tool in java or kotlin

By LiBePosted on Sunday 30 June 2019Sunday 30 June 2019Cat G33k, ProgrammesLeave a comment

This is how "experimented" developers (= developers who know that programs can fail) write code It is ok if you are alone on your project, you can even identify easily your legacy code visually by doing that. It is not (always) ok if you work in a team. Sometimes one might just ask you :… Read More »

Bad code practices : don’t review them, but write code to ban them.

By LiBePosted on Friday 24 May 2019Friday 24 May 2019Cat G33k, ProgrammesLeave a comment

This is getting boring when you are in charge of software quality : "- stop sending primitive values in your parameters""- remove this foreign data structure from the code, it is error prone""- why can't you just isolate this in a separate role ?" I found myself repeating over and over these kind of sentences.… Read More »

Learn how to group expensive calls with the coroutines

By LiBePosted on Tuesday 30 April 2019Tuesday 30 April 2019Cat G33k, ProgrammesLeave a comment

In a micro-service fashion, everything is streamlined to small domains, small actions and therefore fast responses. This is theorically true, BUT. Sometimes we may want to access to expensive in time information. Either a partner api which is slow, or a restricted access to a confidential network which takes seconds to route correctly. You will… Read More »

(storybook) how to extract some source code using webpack

By LiBePosted on Sunday 31 March 2019Sunday 31 March 2019Cat G33k, ProgrammesLeave a comment

If you know storybook well, you may know what storysource addon is. The addon lets you see the caller code responsible for displaying the story (I mean the component) in preview. This looked pretty straightforward and efficient. (see https://storybooks-official.netlify.com/) Since then, several developers wanted to edit the story while on the screen without needing an… Read More »