As most of you will know, every now and then you can expect the question ‘Can you help fix something on this ancient project?’ According to the Universal Software Ageing table, that means anything from last month to much, much older. I got such a question recently, being in-between projects, and this project fell squarely into […]
Spring Data Native Queries and Projections in Kotlin
This blog describes the solution to mapping native queries to objects. This is useful because sometimes you want to use a feature of the underlying database implementation (such as PostgreSQL) that is not part of the JPQL standard. By the end of this blog you should be able to confidently use native queries and use […]
Integrating the AWS Parameter Store with Spring Cloud
I’ll tell you all my secrets (but I lie about my past)— Tom Waits – Tango till they’re sore tl;dr We’ve integrated the AWS Parameter Store with Spring Cloud so that it can be used as a secure configuration backend for services deployed to EC2, including ECS. This code has recently been merged in Spring Cloud […]
Exposing asynchronous communication through a synchronous REST API with Spring 5
On my current project, we opted not to use REST for the communication between our services. Instead we make use of AxonIQ’s AxonHub, which acts as a specialized message broker. Messages can be of three types: Command – You want to change something Event – You want to inform others of something that happened Query […]
Service Discovery using Consul & Spring Cloud
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 […]
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. […]
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 […]
Booting your Microservices Architecture with Spring and Netflix: the aftermath
On 25 November Trifork hosted a webinar in which I gave a short overview of Spring Cloud and its support for the Netflix OSS stack, focusing on Spring Cloud Config and the support for Netflix’s Eureka, Ribbon and Hystrix. We’ve been investigating this stack over the last couple of months and are using parts of […]
City-wide crowd management in Amsterdam
As most residents and visitors of Amsterdam know, every year more people are visiting Amsterdam, city wide events like GayPride, Koningsdag and MuseumNacht are getting bigger and more frequent, putting more strain on the city’s infrastructure and all people living in the city center. That’s why this November 7th, Amsterdam Marketing organized the Museumn8 hackathon […]