Running Selenium in a virtual desktop environment on Linux

Running Selenium tests in a virtual desktop environment on Linux can be particularly useful for isolating the browser and running tests as if they were in a GUI, without interfering with the actual display. A common tool for creating a virtual desktop on Linux is Xvfb (X Virtual FrameBuffer).

First, you need to install Xvfb. You can install it using your distribution’s package manager. For Ubuntu/Debian:

sudo apt-get update
sudo apt-get install -y xvfb

Start Xvfb on a particular display

Xvfb :99 -ac &

Export DISPLAY Environment Variable

You need to tell your terminal session to send any graphical output to the virtual frame buffer set up by Xvfb. You can do this by setting the DISPLAY environment variable.

export DISPLAY=:99

Run Your Selenium Test

Now you can run your Selenium test as you would normally, and it will send its output to the virtual frame buffer instead of trying to use a physical display.

Here is a sample C# code snippet that opens Google in Chrome. Make sure you have the Selenium WebDriver NuGet package and ChromeDriver installed.

using System;
using OpenQA.Selenium;
using OpenQA.Selenium.Chrome;

namespace MySeleniumApp
{
    class Program
    {
        static void Main(string[] args)
        {
            // Initialize ChromeDriver
            using (IWebDriver driver = new ChromeDriver())
            {
                // Navigate to Google
                driver.Navigate().GoToUrl("https://www.google.com");
                
                // Do your test logic here
                
                // Close the driver
                driver.Quit();
            }
        }
    }
}

Stop Xvfb

After you’ve finished running your tests, you can stop the Xvfb process.

killall Xvfb

Configure Xvfb directly within your C# code

To configure a virtual desktop like Xvfb directly within your C# code, you can use the System.Diagnostics.Process class to start and stop the Xvfb process. This approach can be useful for programmatically managing the virtual display environment.

Here’s an example that demonstrates how to start Xvfb, set the DISPLAY environment variable, and then run a Selenium test—all within the C# code.

using System;
using System.Diagnostics;
using OpenQA.Selenium;
using OpenQA.Selenium.Chrome;

namespace MySeleniumApp
{
    class Program
    {
        static void Main(string[] args)
        {
            // Start Xvfb on display 99
            Process xvfbProcess = new Process();
            xvfbProcess.StartInfo.FileName = "Xvfb";
            xvfbProcess.StartInfo.Arguments = ":99 -ac";
            xvfbProcess.StartInfo.RedirectStandardOutput = true;
            xvfbProcess.StartInfo.UseShellExecute = false;
            xvfbProcess.StartInfo.CreateNoWindow = true;
            xvfbProcess.Start();

            // Wait for Xvfb to initialize
            System.Threading.Thread.Sleep(2000);

            // Set the DISPLAY environment variable
            Environment.SetEnvironmentVariable("DISPLAY", ":99");

            // Initialize ChromeDriver
            using (IWebDriver driver = new ChromeDriver())
            {
                // Navigate to Google
                driver.Navigate().GoToUrl("https://www.google.com");

                // Do your test logic here

                // Close the driver
                driver.Quit();
            }

            // Stop Xvfb process
            xvfbProcess.Kill();
        }
    }
}

By using this approach, you can encapsulate the entire process of setting up a virtual display and running a Selenium test in your C# code, making it easier to integrate into your automated testing workflow.