Virtualization using Vagrant for Selenium Tests

Say goodbye to “works on my machine” bugs.

Nobody likes to release software on a Friday. What if something breaks over the weekend? There’s nothing like debugging an issue in production when you’re doing some day drinking at a BBQ.

But you have nothing to worry about, right? I mean, you tested the application and it worked on *your* machine. Too bad that’s never good enough. Have fun working this weekend.

If only you had automated tests for your application (across all of the browsers and all the platforms you cared about). Then you could rest easy this weekend and enjoy the festivities.

Creating a robust and scalable execution environment for automation tests is a very essential phase. In automated tests for web, we actually need to cover different browsers and platforms.

In this documentation, we are going to see how to run our selenium tests in a Linux box using vagrant.

Basically I have a selenium test that works fine when running in different browsers in my Windows host machine. But I want to make sure that it is running fine on the browsers in a Linux box too. Instead of creating an actual VM and running my tests, I am simply going to create a light weight portable Linux box and I am going to run my selenium tests from my windows host machine.

Also every time that you want to run your tests in your local machine, it opens the browser on top of the other windows, preventing you from doing something else. Unless you use Phantomjs or HTMLUnitDriver, it is not possible to run Chrome or Firefox hidden, without disturbing you on your work. Now using Vagrant and VirtualBox, you only need to start the VM, and all your tests will be run into the VM. You can continue developing in the meanwhile!

WHY VAGRANT?

Vagrant provides us easy to configure, reproducible, and portable work environments. Vagrant stands on top of VirtualBox, VMware and some other service providers. If you’re a developer, Vagrant will isolate dependencies and their configuration within a single disposable, consistent environment. If you’re a tester, Vagrant will help you to create light weight Virtual environments to run your tests against all the possible OS + Browser combinations.

Prerequisites:

  1. Download and install Oracle VM Virtualbox – https://www.virtualbox.org/wiki/Downloads
  2. Download and install Vagrant – http://www.vagrantup.com/downloads

From command line, type vagrant –v and make sure that you get the version number that you installed. Vagrant 1.7.21

Vagrant Boxes:

Boxes are the package format for Vagrant environments. A box can be used by anyone on any platform that Vagrant supports to bring up an identical working environment. The easiest way to use a box is to add a box from the publicly available catalog of Vagrant boxes for VirtualBox. We can also add and share our own customized boxes on this website.

I am going to use this box chef/ubuntu-14.04 – a standard Ubuntu 14.04 x64 base install.

Getting Started:

  1. Create a workspace directory to store the vagrant configuration file and shell scripts.

I have created “D:\Automation\Vagrant\Demo”

  1. From Command line go to your workspace and type vagrant init chef/ubuntu-14.04

2

  1. Make sure that the vagrant file is created in “D:\Automation\Vagrant\Demo”
  2. Run the command vagrant up

3If you are running this for first time, it may take some considerable amount of time to download the virtual box image and will put it under C:\Users\<username> \VirtualBox VMs\Demo_default_*

  1. Now the Ubuntu base image VM is up and running. Run the Command vagrant halt. This will power off the VM. Because we need to provision this VM with selenium related libraries, browsers and some utilities to run our selenium tests.
  2. Update the vagrant file in “D:\Automation\Vagrant\Demo” with the following content. Basically the default generated vagrant file has some lot of optional behaviors which are commented by default and you may enable it you need. But we require only the following content in a vagrant file.

 

Vagrant.configure(2) do |config|
   config.vm.box = "chef/ubuntu-14.04"
   config.vm.provision :shell, :path =&gt; "Provisioner.sh"
   config.vm.network :forwarded_port, guest:4444, host:4444
end

Basically what we are trying to do above is enabling port forwarding in the VM. Selenium server will use the 4444 port by default and we are forwarding that port from VM to host machine.

Also we are going to provision this VM using the “Provisioner.sh” shell script. Provisioners in Vagrant allow you to automatically install software, alter configurations, and more on the machine, as part of the vagrant up process. This is useful since boxes typically aren’t built perfectly for your use case. Of course, if you want to just use vagrant ssh and install the software by hand, that works. But by using the provisioning systems built-in to Vagrant, it automates the process so that it is repeatable. Most importantly, it requires no human interaction, so you can vagrant destroy and vagrant up and have a fully ready-to-go work environment with a single command.

Vagrant gives you multiple options for provisioning the machine, from simple shell scripts to more complex, industry-standard configuration management systems. If you’ve never used a configuration management system before, it is recommended you start with basic shell scripts for provisioning.

So to run a selenium test in a new plain OS, we need following things.

  • JDK/JRE – To run the selenium server.
  • Google chrome browser
  • ChromeDriver
  • Some utilities like ‘Unzip’ to extract the chromedriver zip file.
  • Selenium Standalone Server
  • Xvfbor X virtual framebuffer – To run tests in headless mode.

Xvfb is a display server implementing the X11 display server protocol. In contrast to other display servers, Xvfb performs all graphical operations in memory without showing any screen output. So actually when we run our tests in a VM box, we won’t be able to see any browser popping up. It means no GUI interactions are possible. So I am going to install all the above packages along with the dependencies using Provisioner.sh

  1. Create Provisioner.sh in the “D:\Automation\Vagrant\Demo” with the following content.

#!/usr/bin/env bash

# Set start time so we know how long the bootstrap takes

T="$(date +%s)"

#echo 'Updating'

sudo apt-get -y update

echo 'Installing Zip/Unzip'

sudo apt-get -y install zip unzip

echo 'Installing Google Chrome'

sudo apt-get -y install google-chrome-stable

wget https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb

sudo dpkg -i google-chrome-stable_current_amd64.deb

sudo apt-get -y install -f

echo 'Installing Google XVFB'

sudo apt-get -y install xvfb

sudo apt-get -y install -f

echo 'Installing JRE'

sudo apt-get -y install default-jdk

sudo apt-get -y install -f

echo 'Downloading and Moving the ChromeDriver/Selenium Server to /usr/local/bin'

cd /tmp

wget "http://chromedriver.storage.googleapis.com/2.8/chromedriver_linux64.zip"

wget "https://selenium.googlecode.com/files/selenium-server-standalone-2.35.0.jar"

unzip chromedriver_linux64.zip

mv chromedriver /usr/local/bin

mv selenium-server-standalone-2.35.0.jar /usr/local/bin

export DISPLAY=:10

cd /vagrant

echo "Starting Xvfb ..."

Xvfb :10 -screen 0 1366x768x24 -ac &

echo "Starting Google Chrome ..."

google-chrome --remote-debugging-port=9222 &

echo "Starting Selenium ..."

cd /usr/local/bin

java -jar selenium-server-standalone-2.35.0.jar

# Print how long the bootstrap script took to run

T="$(($(date +%s)-T))"

echo "Time bootstrap took: ${T} seconds"

  1. Run vagrant up –provision this will start the VM and then install the list of packages that we have added in the sh and also it will start the selenium server in 4444 port.

4

You can see this by navigating to http://localhost:4444/wd/hub/static/resource/hub.html from your windows host machine [As we have port forwarded].

Now run the following selenium test from any of your favorite IDE.

package test;

import java.net.URL;
import java.util.concurrent.TimeUnit;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.remote.DesiredCapabilities;
import org.openqa.selenium.remote.RemoteWebDriver;

public class HeadlessSession {	  
	  public static void main(String args[]) throws InterruptedException, Exception {	  
		  HeadlessSession.HeadlessSessionId();
	  }
	  
	  public static void HeadlessSessionId() throws Exception {
               DesiredCapabilities capabilities = new DesiredCapabilities();
	       capabilities.setBrowserName("chrome");
	       WebDriver driver = new RemoteWebDriver(new URL("http://localhost:4444/wd/hub"), capabilities);	  
		  try {				
			    String baseUrl = "http://www.google.com";
			    driver.manage().timeouts().implicitlyWait(60, TimeUnit.SECONDS);
			    driver.get(baseUrl);
			    System.out.println("Title : " + driver.getTitle());
			    String browserName = capabilities.getBrowserName().toLowerCase();
			    System.out.println("Browser : " + browserName);
		  } catch (Exception e) {
			  System.out.println(e.getMessage());
		  }
		  finally {
		    driver.close();
		    driver.quit();
		  }
	  }
}

That’s it. Now you have successfully ran your tests in Chrome browser in a Linux box from your windows host machine.

Useful Vagrant Commands:

Command Action
vagrant up Power on the VM
vagrant halt Power off the VM
vagrant reload Restart
vagrant suspend Saving the VM state and sleep
vagrant resume Resuming the suspended VM
vagrant provision Provision the VM by running the Provisioner.sh or any other shell script mentioned in the vagrant file.
vagrant up –provision Power on with provision
vagrant reload –provision Restart with provision

Pros:

  1. Easy to setup and maintain.
  2. It’s free.
  3. Able to clone the production/staging environment for our test execution.
  4. Light weight and portable.
  5. Support to provisioning scripts like Shell, Chef, and Puppet.
  6. Simple command line based workflow.
  7. Goodbye to ‘Works on my machine’ bugs.
  8. For selenium, you can able to run headless tests on your favorite browser.
  9. Create and destroy the VMs as needed.
  10. It works on all major platforms.
  11. We can also use Selenium Grid along with vagrant to run tests parallely across different VM’s.

Cons:

  1. Base boxes for your choice of operating system might not be readily available.
  2. Little bit of time consuming to make vagrant VM up and running.
  3. Taking lot of time when provisioning the VM box. To avoid this, create your own base box by installing all the required dependencies by manually SSH into it and then use provisioning script only for starting the Selenium Server.
  4. Light weight. But looks fatty when considering the alternatives like Docker.
  5. It requires you to have a hard drive file that can be huge and it takes a lot of RAM.