PowerShell: Chrome Automation with Selenium

Selenium is most often associated with QA and testing web sites. DevOps can also make use Selenium in order to automate health checks and a varaiety of administrative tasks. DevOps engineers have numerous logging consolidators, packages and application at their disposal: AppDynamics, SolarWinds, Splunk, etc. There are just times especially with legacy infrastructure or third party sites/applications that browser automation is helpful. A QA engineer would be concerned with Edge, Safari, Firefox, and Chrome. As a DevOps engineer, the focus of this post will be on automation using Selenium and Chrome. There is no reason to test all browser flavors when it is more practical for a DevOps team to standard on a single type of browser such as Chrome.

In a previous post, PowerShell: Install-Module and Uninstall-Module, it was shown how to install the Selenium module for PowerShell and with respect to installation using the all users scope. The Selenium module for PowerShell is an open source project hosted on Git Hub: https://github.com/adamdriscoll/selenium-powershell.

The https://github.com/adamdriscoll/selenium-powershell Git Hub home page includes a Readme.md page which contains a usage section describing how to use the PowerShell module to automate browsers with Selenium:

The URL used to demonstrate browser automation is https://www.google.com. A previous blog post showed how to inspect the element on this page in which the search term is entered, Chrome: Fundamentals of Browser Automation.

The PowerShell code to enter a search term and invoke search via the Enter key is straightforward. The term searched for will be "The Wedding Present Dalliance" which of course refers to the song "Daliance" but the band, The Wedding Present.

The browser automation code is as follows:

$driver = $null
try {
    $driver = Start-SeChrome
    Enter-SeUrl 'https://www.google.com' -Driver $driver
    # The name of the input element is q (name="q")
    # <input class="gLFyf gsfi" maxlength="2048" name="q"     
    $element = Find-SeElement -Driver $driver -Name 'q'
    Send-SeKeys -Element $element `
                -Keys "the wedding present dalliance`n"
}
catch {
    Write-Host $PSItem.Exception
}
finally {
    if ($null -ne $driver) {
        Stop-SeDriver $driver
        $driver = $null
    }
}
Chrome is launched and terminated using the Start-SeChrome and Stop-SeDriver functions which utilize PowerShells try/finally construct to insure that the Chrome is closed even if the script generates an error:

$driver = $null
try {

    $driver = Start-SeChrome

# ... additional code here ....

}

finally {
    if ($null -ne $driver) {
        Stop-SeDriver $driver
        $driver = $null
    }
}

Each browser supported by Selenium has it own start function:

• Start-SeChrome: starts Chrome
• Start-SeEdge: starts the version of Edge that is not implemented with Chromium
• Start-SeNewEdge: starts the version of Edge that is implemented with Chromium
• Start-SeFirefoxL starts Firefox
• Start-SeInternetExplorer: starts Internet Explorer

The URL is assigned using the function, Enter-SeUrl:

    Enter-SeUrl 'https://www.google.com' -Driver $driver

The input element is selected by name using the fuction, Find-SeElement:

    # The name of the input element is q (name="q")
    # <input class="gLFyf gsfi" maxlength="2048" name="q"     

    $element = Find-SeElement -Driver $driver -Name 'q'

The text to search on and the Enter key to invoke search is invoked using function, Send-SeKeys:

    Send-SeKeys -Element $element `

                -Keys "the wedding present dalliance`n"

The result of running the script is the as anticipated search results: