Recent posts

Aug 30, 2018

Tip on migration to Spring Boot 2 when using Flyway

Spring Boot 1.5.x uses Flyway 3 while Spring Boot 2.x uses Flyway 5. According to the official migration guide for Spring Boot 2, you need to do 2 releases to be able to migrate an application from Spring Boot 1 to Spring Boot 2 if you are using Flyway: First upgrade your 1.5.x Spring Boot application to Flyway 4 (4.2.0 at the time of writing), see the instructions for Maven and Gradle.

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Jul 6, 2018

Datadog integration with AWS Elastic Beanstalk for Spring Boot application

If you have an application deployed on AWS Elastic Beanstalk and you want to add Datadog integration to it, then these instructions might help you out. I started out with the instructions at https://www.datadoghq.com/blog/deploy-datadog-aws-elastic-beanstalk/ but they use the older version 5 of the datadog-agent and not the newer version 6. In your source code, you normally have a .ebextensions folder to configure the Elastic Beanstalk deployment. Inside that folder, create the following files (Create directories as needed):

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Jun 10, 2018

PageImpl JSON serialization with Spring Boot 2

During the migration of a Spring Boot application from 1.5.13 to 2.0.2, some of my Spring Rest Docs tests started failing. The reason being that some of my RestController s return a org.springframework.data.domain.PageImpl object (from Spring Data Commons). @RestController public class MyRestController { @GetMapping public PageImpl<SomeDtoObject> listAll() { ... } } With Spring Boot 1.5.13, this results in JSON like this: {"content":[{...},{...},....],"totalElements":50,"totalPages":3,"last":false,"size":20,"number":0,"numberOfElements":1,"first":true,"sort":[{"direction":"DESC","property":"date","ignoreCase":false,"nullHandling":"NATIVE","ascending":false,"descending":true}]} However, with Spring Boot 2.

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Oct 8, 2017

Building an AsciidoctorJ extension to execute JavaScript

I love using Asciidoctor for writing documentation. I mainly got to know it through the excellent Spring REST Docs project. I wanted to build an extension (kind of a plug-in) for Asciidoctor. As I don’t know Ruby, writing an extension in Ruby was a bit too much. Luckily, there is AsciidoctorJ (The JVM version of Asciidoctor) which lets me write extensions in any JVM language. Here, we will be using plain Java, but Groovy for example would work equally well.

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Sep 20, 2017

Using Spring Boot with JavaFX - Using Spring Profiles

In the previous post, I showed ./blog/2017/09/18/using-spring-boot-with-javafx/[how to get started with Spring Boot and JavaFX]. Continuing with the same example, we are going to create a new implementation of the CountryService interface that talks to the Open AQ Platform API so the list of countries will be a lot bigger than our HardcodedListCountryService we have now. Using Retrofit First, we add 2 dependencies in our pom.xml to be able to use Retrofit:

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Sep 18, 2017

Using Spring Boot with JavaFX

In my previous post, I showed how to use JavaFX with the Raspberry Pi 3. I promised there to follow up with a post on using Spring Boot with JavaFX, so here it goes. Just as an example, I will be using the REST API service of the Open AQ Platform API as it is simple and does not require any authentication to get started. Initial Setup We will be using Maven, so we start with a minimal pom.

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Aug 26, 2017

Using JavaFX on Raspberry Pi 3 with Gluon

In this post, I am going to detail the steps to get a simple JavaFX application running on the Raspberry Pi 3 using Gluon. Hardware For this setup, I used the Raspberry Pi 3 with the official 7" touchscreen connected. Raspbian Installation First off, download Raspbian from https://www.raspberrypi.org/downloads/raspbian/. I chose the "RASPBIAN STRETCH WITH DESKTOP" version and burned it on an SD-card using Etcher.

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Jul 24, 2017

Enable preview of Spring REST Docs snippets in IntelliJ IDEA

If you use Spring REST Docs, you will be using the Asciidoctor include directive a lot to include the request and responses that are generated from the unit tests. Drawback is that the Asciidoctor plugin for IntelliJ IDEA will not render them by default and looks like this: The reason is simple, the snippets attribute is only available when running the Maven or Gradle task to build the final documentation.

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Mar 13, 2017

Using ServletUriComponentsBuilder with Nginx

Spring’s ServletUriComponentsBuilder.fromCurrentRequest() can be really convinient to build an URL from the current request. However, when using Nginx, things might work so well. The solution is simple, just add these headers to your Nginx configuration file: proxy_set_header X-Forwarded-Host $host:443; proxy_set_header X-Forwarded-Server $host; proxy_set_header X-Forwarded-Port 443; proxy_set_header X-Forwarded-Proto https; UPDATE 2020-06-08 You need to enable support for this in Spring Boot by setting the following property (Since Spring Boot 2.

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Jan 22, 2017

AssertJ custom assertion for ConstraintValidator tests

As a follow-up to my last post on a ./blog/2017/01/21/custom-validator-to-check-if-a-string-contains-xml/[custom validator to check if a String contains XML], I like to elaborate on how I made the unit test so readable. To repeat, here is part of the unit test again with the assertions highlighted: @Test public void givenNoXml_notValid() { ValidatorFactory factory = Validation.buildDefaultValidatorFactory(); Validator validator = factory.getValidator(); TestObject testObject = new TestObject("This is no XML string"); Set<ConstraintViolation<TestObject>> violationSet = validator.

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