A few months ago I published “Demystifying ELK stack” article that summarizes my knowledge about setting up and configuring the system for collecting, processing and presenting logs, based on Filebeat, Logstash, Kibana, and Elasticsearch. Since then I’ve learned a few new DevOps things which help me and my teammates to work more effectively with ELK. I think they’re worth sharing.

... Read More

Have you ever been in a situation when you discovered an exception in the logs that forced you to spend the next couple of minutes - or even hours - figuring out what exactly went wrong? The message was very cryptic and the only useful information that guided you to the crime scene was a stack trace. And after arriving there, you still had no idea what had really happened and what was the culprit. ... Read More

A year ago, during my trip to one of Software developer conferences, I got a lot of opportunities to discuss variety of topics related to software architecture. Most of them concerned CQRS and CQS patterns. I heard about them many times before but I’ve never had a chance to use them in practice. After getting back from the conference, I decided to give it a shot and try to introduce it in one of my private projects. ... Read More

StaleElementReferenceException can be definitely classified as the number 1 nightmare of people who write automated tests with Selenium framework. This exception occurs when given web element with which we are trying to interact is no longer present in DOM tree. This can be caused by multiple factors, the most common being: an element was removed in the meantime an element was replaced with newer content (for example by Ajax) an element was re-rendered by JavaScript view/template framework In the first case, StaleElementReferenceException indicates the real issue - the app is broken or our automated test case is invalid - whereas the last two cases are mostly caused by UI framework and shouldn’t affect our UI test. ... Read More

When it comes to writing maintainable UI test there always appears the term of Page Object Pattern. For those who are not familiar with Page Object, it’s the approach to building UI test that focuses on creating high-level abstraction over low-level details related to interaction with a tested application. This testing interface encapsulates all the noise related to technology and allows to clearly express intention of test cases. This concept is very well described by Martin Fowler here. ... Read More