Introduction In one of our customer projects we are heavily using Spring Boot in combination with other Spring projects for our microservices. One of the more complex parts of microservices, especially when you are using them as fine-grained as meant to be, will be the fact that you need to setup and maintain the connections […]
Writing less code
Have you had that feeling that you have to write too much code to build simple functionality? Some things just feel repetitive, they feel you should be not have to write them yourself, instead a framework should make your life easier. Recently I’ve been building a project in Java/Spring, and after some time I started wondering […]
Measure the Adequacy of Android Unit Tests with Mutation Testing
Unit tests are an essential tool in a trustworthy test suite for an Android application or any other software system for that matter. But unit tests themselves doesn’t guarantee that the right features or requirements are tested, even if you did a thorough effort to cover as much code as possible in your entire code […]
Collecting data from a private LoRaWAN sensor network into Elastic
Introduction to LoRaWAN and ELK Why LoRaWAN, and what makes it different from other types of low power consumption, high range wireless protocols like ZigBee, Z-Wave, etc … ? LoRa is a wireless modulation for long-range, low-power, low-data-rate applications developed by Semtech. The main features of this technology are the big amount of devices that […]
Server side applications in Apple’s Swift
In 2014, Apple announced the release of Swift, a new programming language for all their platforms. Their programming language of choice on iOS and OSX has always been Objective-c, a language which is a bit dated (it predates C++) and as it has had new features (and syntaxes) bolted onto it every few years, it carries […]
Using Spring Session for concurrent session control in a clustered environment
For a long time, Spring Security has provided support to limit the number of sessions a single user can have concurrently. This prevents users from being logged in from many different devices at the same time, for example to ensure that they won’t share their credentials to a paid site with their friends and family. […]
From The Trenches: LoRa, LoRaWAN tutorial with the LoRaBee
Once in a while you stumble across an interesting technology which is an enabler of new solutions, and new business cases. At Trifork Eindhoven we believe LoRa / LoRaWan might be such a technology. We are currently working on several Internet of Things solutions which could directly benefit from long distance communication, with a low energy […]
Spring-AMQP and payload validation: some notes from the trenches
It’s been a while since I’ve written one of our from-the-trenches blogs: that’s mostly because I’ve been very busy in those trenches developing systems for our customers. This week I completed a Spring Boot-based microservice which is responsible for interacting with some 3rd party SOAP service: its own clients communicate with it by sending request […]
Elastic{ON} 2016
Last week a colleague and I attended Elastic{ON} in San Francisco. The venue at Pier 48 gave a nice view on (among others) the Oakland Bay Bridge. Almost 2000 Elastic fanatics converged to listen to and talk about everything in the Elastic Stack. I have been to a lot of sessions. I think the two […]
Personalised city trip itinerary using integer linear programming
Case As a research project I have developed an itinerary service. The idea started when I was doing a hackathon with colleagues for the city of Amsterdam (see earlier post). I wanted to recommend an itinerary to a tourist visiting the city of Amsterdam. Furthermore, I wanted to make the itinerary based on the user’s interests to recommend […]