Focus

Testing

Articles, podcasts, talks, and more about Testing.
Podcast

Die Reise der Zalando Reliability Organisation

Zu Gast: Heinrich Hartmann, 
Principal SRE
, Zalando

Sven Johann
Blog Post

Testing your GitLab CI/CD pipeline

If you develop a pipeline as a service for other development teams you should treat it as a product and establish product development processes, a versioning strategy, etc. around it. Besides that, as potentially many teams will use and rely on your pipeline you want to make sure that new features don’t break existing functionality. This ensures that your customer base remains happy and able to deliver business value. Therefore you need some sort of testing and we will demonstrate a way to (integration-) test your GitLab CI/CD pipeline.

Article

Containers for tests and local development with Spring Boot 3.1

Spring Boot test containers & Docker Compose

Article

Testing in Spring Boot applications

In addition to production code, we typically also write tests to discover and correct possible errors as early as possible in the development process. For new functionality, it isn’t even uncommon to write more test code than production code. At the same time, the tests should be as fast as possible, so they can be executed frequently without causing long delays. In this article, we explore how this can be done in applications based on Spring Boot.

Article

An Introduction to TLA+ and Its Use in Parties

TLA+ is a system for modeling all possible states of a system. On this model, you can then verify certain properties of this system. Smart people can use this to check that their thread scheduling runs all threads equally, or that their work queue will never overflow. In this article, we’ll try and verify the fraught process of ordering pizza for a pizza party as a small introduction to the concepts and syntax of TLA+.

Article

Property-based Testing with “fast-check”

1000 in one blow

Article

Diverse Themen und Bibliotheken für Tests in und mit Java

In diesem Artikel betrachten wir bunt gemischt diverse Themen und Bibliotheken rund um Tests für und mit Java. Dabei folgen wir keinem roten Faden, sondern lassen uns durch das übergreifende Thema treiben.

Blog Post

Test organization and naming

As our system grows, so will our test suites. For our production code, we have learned techniques to keep it maintainable. For example, we try to structure our logic into sub-aspects, put them in specific locations and give the units meaningful names. We want to achieve the same for our tests. One of the main goals is that a developer - or generally speaking, the person who has to maintain the test - knows where to find which test. We also want to understand as quickly as possible what the test is for and what might be the reason for a failing test.

Blog Post

Test Strategy
Blog Post

Tests Granularity

In two previous posts we discussed the benefits of automated tests and the properties of a good test. So far we were trying to avoid differentiating the tests in any way. This time we want to address one way how tests can be classified: tests granularity.

Blog Post

Anatomy of a Good Test

In our last post, we focused on why we should write tests and what value they provide. This time we will go far more technical and take a look at a single test. We will show what makes a test a good one and describe desired and unwanted properties. Interestingly enough, all those properties hold, no matter how isolated or integrated the test is. This already gives us a hint that all tests are alike, we should remember that. Unfortunately, as the topic is very broad, we will have to skip some aspects that play a role when we’re talking about test suites. We will get back to them in one of our next posts.

Blog Post

Why you should write automated tests
Blog Post

Cross-platform testing of TypeScript code with Jasmine and Karma

I like TypeScript. Writing code that already underwent basic checks (i.e. typechecking) before it can even touch an execution engine is a big win in my book. In particular, TypeScript is nice because it integrates well into the broader JavaScript ecosystem and comes with batteries (i.e. types) included. Unfortunately, most test runners require extra setup to work with tests written in TypeScript. Some even require staggering amounts of configuration.

Blog Post

About unit and integration tests

The terms unit test and integration test are typically used as something different, or even opposite. In this blog post I explain why this is misleading and how I prefer to talk about isolation vs. integration instead.

Blog Post

What Could Possibly Go Wrong

Polyglot Party with Nextjournal

Article

JUnit5 für das Testen von Spring Boot-Anwendungen

Bei der Entwicklung von Spring und Spring Boot wurde schon immer darauf geachtet, dass hiermit entwickelte Anwendungen testbar sind. Ab und zu reichen die im Standardumfang mitgelieferten Mittel jedoch nicht vollkommen aus. In diesem Artikel wollen wir uns deshalb an drei Anwendungsfällen aus der Praxis anschauen, wie sich die vorhandenen Mittel in Kombination mit JUnit5 erweitern lassen.

Podcast

Testen von Microservices

Erfahrungen mit End-to-End Tests

Lucas Dohmen
Torsten Mandry
Blog Post

Testen von Microservice-Systemen
Article

Java-Bibliotheken für den Einsatz in Tests

In den meisten Projekten entfällt ein nicht gerade kleiner Anteil des Codes auf Tests. Für diesen Testcode sollten dieselben Regeln wie für Produktivcode gelten. Neben dem Achten auf Verständlichkeit und Wartbarkeit gehört auch das Erschaffen von Abstraktionen und das Vermeiden des Not-invented-here-Syndroms durch den Einsatz von passenden Bibliotheken dazu. Dieser Artikel stellt sechs Bibliotheken vor, die sich im Einsatz als praktisch und hilfreich erwiesen haben.

Blog Post

Testing is storytelling

Tests do not only exist to verify the absence of known bugs. They’re also documenting the expected behaviour of a system. Moreover, they’re showing developers how to use code.

Article

Generierung von Regressionstests für Legacy-Code

Testfälle auf Knopfdruck?

Blog Post

A Playground for Testing OpenID Connect

This post describes how you can set up a development environment in order to play around with your OpenID client implementation. When running your application in a cluster, it can be difficult to test how it will behave behind a load balancer. One factor that can be particularly difficult to test is when you are communicating with an OAuth 2.0 or OpenID Connect server which expects that a request will be redirected back to the same application instance that it came from.

Blog Post

Spring-less testing

Spring is a great project, it helps a lot with common, usually mundane, tasks. But it’s not always unicorns and rainbows. Too much Spring in tests can cause a few issues like long execution time and fragility. Here, I’m showing how to avoid such pitfalls.

Article

Consumer-Driven Contracts – Testen von Schnittstellen innerhalb einer Microservices-Architektur

Pacta sunt servanda

Article

Auf Nummer sicher

Neue Projekte im Geschäftsprozess-Umfeld stehen häufig vor der Herausforderung, Prozesse zu automatisieren. Dabei müssen Prozesse so formal beschrieben werden, dass ein Computer sie, wie andere Software auch, interpretieren und ausführen kann. Dieses High-Level-Programming verlangt aber auch die Qualitätssicherung, insbesondere von kritischen Prozessteilen. In diesem Artikel werden Möglichkeiten für das Testen der verschiedenen Komponenten von ausführbaren Geschäftsprozessen (Prozess, Datentransformationen) und für das Review (Prozess, Servicedefinitionen) sowie Erfahrungen aus einem Projekt vorgestellt.

Article

Testobjekt: Geschäftsprozess – Testen für kontinuierliche Verbesserung

Die Automatisierung von Geschäftsprozessen mittels WS-BPEL oder BPMN 2.0 steht in der heutigen Zeit oftmals im Focus der IT-Strategien von Unternehmen. Geschäftsprozesse werden dabei nicht mehr nur fachlich modelliert, sondern so formal beschrieben, dass sie mittels Prozess-Engines ausgeführt werden können. Diese formalen Modelle sind zwar abstrakter und näher an den fachlichen Geschäftsprozessen als normale Programme, sind aber trotzdem Softwareartefakte, die während der einzelnen Entwicklungszyklen und auch bei späteren Anpassungsarbeiten getestet werden müssen.