How to make a software developer happy ?

Leave your comfort zone

To be or not to be (happy), that’s the question. In this article, I expose some thoughts about what could make a software developer happy in his work. I wrote this article with several targeted audience in mind : Junior developers, Senior Techleads and H&R resources.

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Using S3 libraries with Minio mock server

Minio WebUI

In the continuation of my previous S3 article,

I present you, how to write a S3 Java Sample program that is using a mock S3 server to develop the functionalities.

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Java developer testing toolbox

JBehave : code

An article dealing with Java application and testing frameworks and related libraries. Continue Reading


CompletableFuture and Java 8 Reactive

java completablefuture

I have bene using recently Java 8 new features CompletableFuture.

It works the same way as javascript promises but with a crazy hard to remember syntax and plethora of methods.

I found this great webpage to guide me through the API :

Guide To CompletableFuture

The result is this new version of the CQRS Module :


Fore more informations about that module, check there :


An example of code is here.


How to implement CQRS with Spring : new framework

This article is a presentation of a new little framework, I have developed and used on several projects.

The framework is for Spring Framework and requires Java 8.0. The code is on GitHub and downloadable from Bintray or JCenter.

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Writing an integration test with a mail server

This is a simple example of code to demonstrate how to use the library fakesmtp-junit-runner to write integration tests.

The library has been released on GitHub and Maven Central. Continue Reading


TOP open-source dashboard solutions 2017

Dashboards can be a very efficient communication tool for a team, between managers and business units. It enables an organization around a vision to share common goals. It can also be useful to identify weaknesses in processes and adapt your strategy according to them.

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Test and Data Generation for Java Unit tests

Today I was preparing a presentation about Software Code quality for a TechTalk on Thursday. I made a search on Internet about Automatic Unit test generator and Data Generators. I will present some tools I have tried. Today, we will speak of Randoop.

Randoom Test Generator

Randoom Test Generator

The first tool name is Randoop.. This tool is existing since 2007 and its purpose is to generate automatically unit tests 🙂 Directly from your class definition!

To use it you have two choices:

  • You can use your software JAR or classpath directory.
  • You can include it in your test compile path (on gradle or maven) and creates a main or unit test.

To explain short the theory, thanks to the Java reflection it’s quite easy to produce automatic tests validating some contracts of your API.

Some examples: – toString() should never returns null or throws an Exception – equals() and compareTo() methods have a long list of constraints – Reflexivity: o.equals(o) == true – Symmetry: o1.equals(o2) == o2.equals(o1) – Transitivity: o1.equals(o2) && o2.equals(o3) ⇒ o1.equals(o3) – Equals to null: o.equals(null) == false – It does not throw an exception

Therefore this tool is generating unit tests with JUnit(TestSuite) for the list of classes you provide.

I have done some tests and you can reach 50-60% of coverage quite easily.

The main drawbacks of the solution are: – The unit tests are drawing a snapshot (precise picture) of your code and its behaviour however some tests are really non-sense and you don’t want to edit them. – They don’t replace handwritten tests since the tool is not understand the different between a String parameter emailand fullName. He will mostly use dumb strings.

About the technology, it’s not production ready: – I had troubles with the jar and its dependency plume. – The JAR is a fatjar and coming with dependencies that broke my software.

In conclusion, I will fork the software and try to fix the problems to make it more popular 🙂


Stop/Remove All Docker containers

Stop / remove all Docker containers

Hints to use with docker.

In the version 1.13.x and higher :

Remove all unused containers, volumes, networks and images (both dangling and unreferenced).

docker system prune

Link : doc docker

Removes all stopped containers.

docker container prune

Link : doc docker

Hack and hints

There are many ways to stop/remove all Docker containers.

 On Unix/Linux :

docker stop $(docker ps -a -q)
docker rm $(docker ps -a -q)


docker rm -f $(docker ps -a -q)

For All images :

docker rmi $(docker images -q)

Remove all containers and volumes :

docker rm -v $(docker ps -a -q)

Stop faster docker images :

docker ps -a -q | xargs -n 1 -P 8 -I {} docker stop {}


FOR /f "tokens=*" %i IN ('docker ps -a -q') DO docker rm %i


docker rm @(docker ps -aq)

Link :


SonarQube and ReactJS

This article is showing you how to use SonarQube with ReactJS and its JSX files. I will use both SonarQube JavaScript plugin and the additional plugin Sonar EsLint plugin.

<%- toc(str, [options]) %>

For the people who has missed my previous article, I have created a new SonarQube plugin to extends the Javascript analysis.

Installation and Configuration

The first step is to download the plugin directly from Github here.

Download the plugin

Download the plugin

Find the latest release.

Find the latest release

Find the latest release

Copy it in your Sonar extension folder.

Copy the plugin

Copy the plugin

Restart the server

Restart the server by calling the commands (here on linux)

  âžś  sonarqube-6.0 ./bin/linux-x86-64/sonar.sh stop
  Stopping SonarQube...
  Waiting for SonarQube to exit...
  Stopped SonarQube.
  âžś  sonarqube-6.0 ./bin/linux-x86-64/sonar.sh start

 Enabling custom rules in SonarQube

Don’t forget to modify your SonarQube profile to enable the new ESLint rules :

Add the ESLint rules to your SonarQube profile

Add the ESLint rules to your SonarQube profile

Enable the ESLint rules to your SonarQube profile

Enable the ESLint rules to your SonarQube profile

Preparing your project

 Handling SonarQube Scanner

Most projects requires the SonarQube scanner (Wiki Link to analysis Javascript. Download it somewhere on your disk and unzip it.

Creates a file sonar-project.properties̀ into your project.

Copy-paste this content and modify it :

sonar.projectName=ReactJS demo

Don’t forget the line sonar.javascript.file.suffixes=.js,.jsx, it’s the hack to make SonarQube working on JSX files!

OK! SonarQube Scanner is configured!

Preparing ESLint

We want to perform the SonarQube analysis with the additional results of ESLint. Eslint is a popular linter that provides recent rules for many javascript frameworks – ReactJS included.

ESLint is thereby often upgraded and contains through its extension system, rules and frameworks that you won’t find in the regular SonarQube installation.

If you haven’t created yet an ESLint configuration file, here is the commands :

ESLint Configuration

ESLint Configuration

You can try the configuration by launching ESLint ony your project. It may warn you that some extensions are missing. Install them with NPM or Yarn.

Missing NPM Module

Missing NPM Module

Usually, the ReactJS extension is missing of your project. You can add them like developer extensions (--save-dev) or globally (-g).

Install missing ESLINT ReactJS extension

Install missing ESLINT ReactJS extension

With the right configuration and ESLint installation, the scan of a JSX File should work :

Scanning JSX File

Scanning JSX File

OK! ESLint is configured!

 Launching SonarQube Scanner

Launchs the SonarQube scanner with the command :


And the analysis is running …

âžś  react-jsx git:(master) âś— ~/tools/sscanner/bin/sonar-scanner
INFO: Scanner configuration file: /home/sleroy/tools/sscanner/conf/sonar-scanner.properties
INFO: Project root configuration file: /home/sleroy/git/react-jsx/sonar-project.properties
INFO: SonarQube Scanner
INFO: Java 1.8.0_121 Oracle Corporation (64-bit)
INFO: Linux 4.10.0-21-generic amd64
INFO: User cache: /home/sleroy/.sonar/cache
INFO: Load global repositories
INFO: Load global repositories (done) | time=211ms
INFO: User cache: /home/sleroy/.sonar/cache
INFO: Load plugins index
INFO: Load plugins index (done) | time=14ms
INFO: SonarQube server 6.0
INFO: Default locale: "fr_FR", source code encoding: "UTF-8" (analysis is platform dependent)
INFO: Process project properties
INFO: Load project repositories
INFO: Load project repositories (done) | time=214ms
INFO: Load quality profiles
INFO: Load quality profiles (done) | time=94ms
INFO: Load active rules
INFO: Load active rules (done) | time=897ms
INFO: Publish mode
INFO: -------------  Scan ReactJS demo
INFO: Load server rules
INFO: Load server rules (done) | time=482ms
INFO: Base dir: /home/sleroy/git/react-jsx
INFO: Working dir: /home/sleroy/git/react-jsx/.scannerwork
INFO: Source paths: src
INFO: Source encoding: UTF-8, default locale: fr_FR
INFO: Index files
INFO: 9 files indexed
INFO: Quality profile for js: Sonar way
INFO: Sensor Lines Sensor
INFO: Sensor Lines Sensor (done) | time=41ms
INFO: Sensor SCM Sensor
INFO: SCM provider for this project is: git
INFO: 9 files to be analyzed
INFO: 0/9 files analyzed
WARN: Missing blame information for the following files:
WARN:   * /home/sleroy/git/react-jsx/src/example/hello.jsx
WARN:   * /home/sleroy/git/react-jsx/src/example/index.jsx
WARN:   * /home/sleroy/git/react-jsx/src/fixtures/this.jsx
WARN:   * /home/sleroy/git/react-jsx/src/example/index.js
WARN:   * /home/sleroy/git/react-jsx/src/example/imager.jsx
WARN:   * /home/sleroy/git/react-jsx/src/fixtures/component.jsx
WARN:   * /home/sleroy/git/react-jsx/src/fixtures/advanced.jsx
WARN:   * /home/sleroy/git/react-jsx/src/fixtures/react.jsx
WARN:   * /home/sleroy/git/react-jsx/src/fixtures/hello.jsx
WARN: This may lead to missing/broken features in SonarQube
INFO: Sensor SCM Sensor (done) | time=504ms
INFO: Sensor XmlFileSensor
INFO: Sensor XmlFileSensor (done) | time=1ms
INFO: Sensor JavaScript Squid Sensor
INFO: 9 source files to be analyzed
INFO: 9/9 source files have been analyzed
INFO: Unit Test Coverage Sensor is started
INFO: Integration Test Coverage Sensor is started
INFO: Overall Coverage Sensor is started
INFO: Sensor JavaScript Squid Sensor (done) | time=893ms
INFO: Sensor Linting sensor for Javascript files
INFO: Sensor Linting sensor for Javascript files (done) | time=1438ms
INFO: Sensor Zero Coverage Sensor
INFO: Sensor Zero Coverage Sensor (done) | time=38ms
INFO: Sensor Code Colorizer Sensor
INFO: Sensor Code Colorizer Sensor (done) | time=2ms
INFO: Sensor CPD Block Indexer
INFO: DefaultCpdBlockIndexer is used for js
INFO: Sensor CPD Block Indexer (done) | time=1ms
INFO: Calculating CPD for 2 files
INFO: CPD calculation finished
INFO: Analysis report generated in 170ms, dir size=24 KB
INFO: Analysis reports compressed in 254ms, zip size=18 KB
INFO: Analysis report uploaded in 39ms
INFO: ANALYSIS SUCCESSFUL, you can browse http://localhost:9000/dashboard/index/sleroy:reactjs-demo
INFO: Note that you will be able to access the updated dashboard once the server has processed the submitted analysis report
INFO: More about the report processing at http://localhost:9000/api/ce/task?id=AVwHr7JyDHBkCqlFC7Sx
INFO: Task total time: 8.046 s
INFO: ------------------------------------------------------------------------
INFO: ------------------------------------------------------------------------
INFO: Total time: 10.141s
INFO: Final Memory: 48M/301M
INFO: ------------------------------------------------------------------------

Controlling the results

Go to your Sonar interface, and jump directly to the dashboard.

Our project has been analyzed.

SonarQube analysis

SonarQube analysis

We observe that the violation’s number is increasing with the new rules.

SonarQube analysis details

SonarQube analysis details

Hourra, our JSX files are analyzed !

JSX Analysis

JSX Analysis

In this article, we have installed, configured a new plugin to perform better Javascript analysis into SonarQube, working with ReactJS and JSX files.