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

Let’s assume that your system consists of a few microservices. Everything must have high availability so each microservice has at least two active instances on separate machines and everything must be multiplied by the number of testing and production related environments. When there is a situation that requires log analysis you have to skip from server to server looking for the file with desired information. You browse each file using some kind of notepad-based editor and if the files weight hundreds of megabytes it’s quite a challenge. ... Read More

Over a year ago I heard for the first time about the ELK stack. Since then I’ve had an opportunity to help five teams to implements ELK as a part of their development process (one team is using it on production, the rest of them so far only in development environment). ELK stands for ElasticSearch-Logstash-Kibana and it’s a set of services that helps to improve productivity in the area of logging, covering aspects of collecting, processing, storing and presenting log data. ... Read More

My laptop stores everything on 250 GB SSD hard drive (actually Windows sees it as 223 GB), so from time to time I’m running out of free space. When there is a need I’m starting clearing-up by emptying c:\Users\user_name\AppData\Local\Temp\ and c:\Users\user_name\Downloads\ directories (the second one against all appearances is often full of unnecessary files). When this is not enough I use WinDirStart to analyze my hard disk usage. This simple but extremely useful tool presents directory tree with attributes related to disk utilization such as: size, usage percentage, number of items (files and subdirectories), etc. ... Read More