Agile/Scrum blog

Onderwerp: Continuous delivery

"Dont Roll-Back, but Fail Forward"​

Willem Vermaak Door: Willem Vermaak,  10-03-2017
Onderwerp: Software Release  Continuous Delivery  

Let me start by admitting that the quote is not mine. I wish I was able to come up with this. The credits to this remark go to a software engineer I worked with during my time at

Differences between Continuous Integration, -Delivery and -Deployment explained

Pieter Versteijnen Door: Pieter Versteijnen,  24-06-2015
Onderwerp: Continuous delivery  Continuous Integration  Continuous Deployment  

After attending a conference we came to the conclusion that there are a lot of people interpreting Continuous Integration, Continuous Delivery and Continuous Deployment different. That’s why we wrote this blog to make clear what is the difference and what are the benefits when taking the next step.

What do Agile Testing and painting a wall have in common?

Harm Pauw Door: Harm Pauw,  12-06-2015
Onderwerp: Testing  Continuous delivery  

I always like to use real-world metaphors in order to explain technical topics. This time I'd like to explain the Agile Testing Pyramid in  Agile Testing by comparing it to painting a wall. Curious? Please continue reading!

UI tests with Selenium - Docker and on-demand Grids

Harm Pauw Door: Harm Pauw,  24-03-2015
Onderwerp: Continuous delivery  CD  Testing  Tooling  

This blog post is the third blog post about UI test with Selenium. In the previous blog, we looked at Selenium Grid and how it can help you in executing browser tests using real browsers. Unfortunately, running a Selenium Grid also has some downsides, like the need for quite some infrastructure and maintenance. In this blog, we'll take a look at Docker and see how we can use it to overcome some of these downsides.

Why Continuous Delivery? Start with the customer in mind!

Marco Kroonwijk Door: Marco Kroonwijk,  24-03-2015
Onderwerp: CD  Continuous delivery  Prowareness  

At the beginning of 2015 we had a great session with a lot of Prowareness customer representatives, in which we asked them to provide feedback on our past performance and future plans. One of the topics being discussed was the introduction of Continuous Delivery (CD) in their organization. Most surprisingly, many customers asked us why they should start with it, because that was not such an obvious thing to them. We got signals that we had overrated the familiarity with, and awareness of, the benefits of CD. This was worth exploring further.

My Favorite Continuous Delivery Tools - Part I: Ansible (configuration management)

Maarten Kossen Door: Maarten Kossen,  23-03-2015
Onderwerp: Continuous delivery  Practices  Tooling  

In this series of blog posts I will share my favorite Continuous Delivery tools with you. For each of these tools I will highlight why it is useful and in which part of the Continuous Delivery chain it can be used. During this series I will cover the following tools:

  • Ansible
  • Docker
  • TeamCity
  • Git

The problem

Managing a single server is quite easy. You just install the software you need and configure it as you see fit, no harm done and not a pain to maintain. When adding a second server to your setup you get a little challenge. You want it to be identical to the first server and you start copy-pasting config files around after having installed the same software. Then you add the third server...

As you may notice, the above solution doesn't scale well (among some other issues). It especially doesn't scale well in a business or an enterprise environment where you don't just have "a server" or "a configuration" but you have multiple clusters or servers each with their own configuration. Managing, and keeping homogenous, multiple database servers (for example) can become a tedious task. For these situations, you need a tool to work with all these servers. Not only to set them up (install software and apply a configuration), but also to update them (both software updates and configuration updates) as well as keeping them homogenous (ensuring they all have identical software installed and an identical configuration).

Luckily, there are solutions for this problem. I'm going to show you my favorite one in this blog post: Ansible.

Jenkins plugin "Testgrid for Selenium tests" online!

Harm Pauw Door: Harm Pauw,  12-03-2015
Onderwerp: Continuous delivery  

This blog post is a little bit different than a usual one. Instead of discussing a particular topic, I’d like to share the location of a open source project we’ve been working on. The details of this project will be presented during the CD Market of Prowareness.

In the last couple of months, we worked on a solution to make it easy to run Selenium tests using real browsers without having to configure a complete Selenium Grid from the ground up. The solution uses Docker to create an on-demand Selenium Grid each time Jenkins triggers a new build. After the job completes, it automatically stops and discards the Grid.

The Jenkins Plugin and Docker images are hosted on Github and Docker Hub:

This is of course still work in progress, so let us know what you think and try to regularly take a look at new versions!

UI tests with Selenium - Testing on Multiple Browsers using Selenium Grid

Door: Harm Pauw & Robert van Vark,  04-03-2015
Onderwerp: Continuous delivery  CD  CI  Tooling  Testing  

This blog post is the second one in the series of “UI tests with Selenium and more”. This post will be about Selenium Grid, how it’s often used to test with multiple browsers and the challenges you face with supporting infrastructure.

In the previous blog we discussed Selenium WebDriver, why people often use it in combination with HtmlUnit instead of real browsers, and why it is not that smart to use HtmlUnit only. In case you’ve forgotten: none of your real customers actually uses HtmlUnit, as it doesn’t have a GUI. Also, it is not possible to take screenshots since there’s no rendered page to capture.

The main reason for teams to use HtmlUnit is that it can run easily on your headless build server. Also, it would be very time-consuming to manually create individual suites of automated tests for every OS / browser combination that your customers use. Fortunately, Selenium provides a framework of doing exactly that: Selenium Grid. With Selenium Grid, you can set up a grid of multiple browsers and OS combinations that you can use in your tests. What makes it better is that your tests can be completely browser and OS agnostic. This enables you to use the same test suite to test multiple browser and OS combinations.

Selenium Grid’s architecture consists of several Nodes and one central Hub. A Node can provide one or more browsers, e.g. Chrome and Internet Explorer, on a specific operating system. The Grid is controlled from a central place called the Hub.

Running your automated tests only requires that you create a RemoteWebdriver object, provide it with your wishes regarding the browser and OS and point it to the URL of the Hub. The Hub takes care of distributing your tests to a node that satisfies the browser/OS combination you requested. You can also specify the number of concurrent browser instances on each node, so that you can run your tests in parallel. There’s also a web based Console that - although it’s a little bit primitive - allows you to see the status of each node.

If you only want to test using one particular browser, it’s not necessary to have a separate Hub and Node. In this case, you can start a Standalone server which acts like both a Hub and Node. You can use it in exactly the same way as a grid with a hub and multiple nodes.

You’ll need some infrastructure to create a grid: either in the form of physical servers or virtual machines running on a server on-premise or in the cloud. The setup and maintenance of this grid costs effort and money, even if it’s only used for short periods. For this reason, companies often let multiple applications use the same grid: that way the grid is used more efficiently.

However, sharing a grid with multiple applications also has some downsides. Often the usage of a grid is not evenly distributed so during “rush hours” you can have a queue of tests that wait until they can be executed. This could lead to long execution times and false positives due to timeouts. Also, if the tests of one application are taking a long time to run or even hang (caused by timeouts or other problems), they could seriously affect tests from other applications.

An ideal solution for these problems is to have a completely new and fresh grid every time you start a new test run. This way, test runs for different applications don’t interfere with each other and when a test run goes bad, subsequent test runs are not affected by it. But booting physical and even virtual machines takes up quite some time, so this is not very practical.

In the next blog post we’ll take a look at Docker and see how we can apply this tool to provision on-demand Selenium Grids while avoiding long startup times and other problems.

Technical Agile Coach

Door: Marco Kroonwijk ,  23-02-2015
Onderwerp: Technical Coach  Continuous Delivery  CD  Extreme Programming  XP  Agile Coach  Technical Debt  Architecture  Development Team  Role  Craftsmanship  Practices  

A while ago, I started working at Prowareness, and as new employees we choose our own role title best fitting our experience, skills, ambition and passion. I chose the title of Technical Agile Coach, without really having defined what it actually is. It just felt right!

However, occasionally, people ask me what a technical coach does and what the difference is with “other” Agile Coach titles. So here’s what that answer is, for me.

UI tests with Selenium - About Selenium

Door: Robert van Vark & Harm Pauw,  16-02-2015
Onderwerp: Testing  Tooling  Continuous delivery  CD  

This blog post is the first one in the series of “UI tests with Selenium”. This post will be about Selenium, how it’s often used and the problems that could arise when using it an a CI setup.

Selenium is one of the most used frameworks to create tests that interact with the browser. There are two flavors: Selenium IDE and Selenium WebDriver. The former is is not well suited for creating and maintaining test suites due to it’s record-and-playback setup: recorded tests are difficult to maintain and become outdated quickly. Selenium Webdriver provides a programmer with an API to interact with the browser in a uniform way. In combination with a test framework like jUnit, TestNG or Cucumber, a programmer can create UI tests in similar way as creating unit tests. Additionally, Selenium has features to record screenshots during the tests, which facilitates analyzing failures of your test runs.

Setup CI build on VS Online - Hosted build controller

Prajeesh Prathap Door: Prajeesh Prathap,  01-01-2015
Onderwerp: Continuous delivery  TFS  agile  git  CI  

With your VSO account and team projects created using the account, it’s very easy to have full ALM capabilities integrated to your
project. Once you have chosen the version control for your project you can easily hookup a build definition and create CI builds using the hosted build controller provided as part of VS online.
If you are using the hosted build controller, there is no need of any additional hardware resources that needs to be installed or
configured for setting up a CI build. Read more..

Continuous Delivery – Patterns for zero downtime requirements (ARR setup)

Prajeesh Prathap Door: Prajeesh Prathap,  17-08-2014
Onderwerp: Continuous delivery  CD  zero downtime deployment  agile  architecture  

Microsoft Application Request Routing (ARR) is a proxy-based routing module that forwards HTTP requests to application servers based on HTTP headers, server variables, and load balance algorithms. With ARR you can increase application availability and scalability by better utilization of content server resources with lower management cost by creating opportunities for shared hosting environments.

Continuous Delivery – Patterns for zero downtime requirements

Prajeesh Prathap Door: Prajeesh Prathap,  27-07-2014
Onderwerp: Continuous delivery  CD  zero downtime deployment  agile  architecture  

One of the main problems teams face when practicing continuous delivery is to manage zero downtime deployments to the production environments. The goal is to deploy as soon as possible and depending on the heartbeat of the organization, this becomes a higher priority to manage active users without losing their data and sessions during a deployment process. In this post I'll share some of the ideas and approaches that are been used for achieving the goal of zero downtime deployments.

An important process for reducing risks and managing a zero deployment downtime is by following the blue-green deployment technique. In a blue-green deployment scenario, the approach is to bring up a parallel green environment and once everything is tested and ready to go, you simply switch all the traffic to the green environment and leave the blue environment idle. This also helps in easy rollback and switch to the blue environment if anything goes wrong in the current installation.