Pester powershell
![pester powershell pester powershell](https://i.ytimg.com/vi/o4ihc7atwYQ/maxresdefault.jpg)
One way to build that test would be to define a describe block with the name of the service and the computer it's being tested on.
![pester powershell pester powershell](https://ironscripter.us/wp-content/uploads/2020/06/tree_thumb-199x300.png)
Let's say I want to ensure the wuauserv service is running on a server of mine.
#Pester powershell code#
Once we have the code to perform the tests, we need to start scaffolding out a Pester test to run the code and then compare the result against the expected outcome. (Get-Service -ComputerName -Name ).Status It is also a base for tools that validate whole environments, computer deployments, database configurations and so on. Pester is most commonly used for writing unit and integration tests, but it is not limited to just that. Pester provides a framework for writing and running tests. I will admit, that I hadn’t, until this point, taken a look at Pester and this seemed like a great opportunity. Pester is a testing and mocking framework for PowerShell. The status is probably going to either be Running or Stopped. The best way to repeatedly test PowerShell functions, CMDLets, modules and scripts is through the use of Pester. This code snippet queries a remote server's service and returns its status. For this example, a code snippet like the one below would work fine. The first task is building the code to test for this scenario. If the service is stopped, that's a problem, and you'd like to know about it. Doctor Scripto Scripter, PowerShell, vbScript, BAT, CMD. Tests.ps1, and then run the Invoke-Pester cmdlet. How do I run Pester tests Place your tests into a file with a name that ends with.
#Pester powershell how to#
To use an example, let's say you have a Windows service that you expect to be running on all of your servers. Summary: Learn how to start a Pester test. Pester can test for anything PowerShell can read. We won't cover how to write Pester tests in this article, but if you'd like to learn more, I encourage you to check out The Pester Book, written by me, which goes in-depth on Pester and how to build tests.īefore we can begin writing a test, we first need to figure out what it is we're going to test in the first place.
![pester powershell pester powershell](https://adamtheautomator.com/wp-content/uploads/2019/07/pesterbook.png)
This DSL describes the desired state and has the code necessary to check that state and to compare the result.Ī Pester test can be broken down into a hierarchy of components such as a describe block, a context block and an it block. Infrastructure tests in Pester are PowerShell code that's executed by the Pester PowerShell module and built in a specific way, known as a domain-specific language (DSL). Does that file server have the expected folder hierarchy?.When I run this PowerShell script, does it create the correct user account?.
#Pester powershell software#
Does that server have the right software installed on it?.But first, what is an "infrastructure test" anyway?Īn infrastructure test is a generic term for any code that you write to test a current state against an expected state. We will look at those concerns in some of the upcoming articles.Pester infrastructure tests can run as standalone tests or be integrated into a broader automation workflow. The It function handles more concerns than just error handling and output that we described in this article. They execute input ScriptBlock and handle every possible exception.ĭo not worry if the implementation of Test-Case seems too simplified in comparison to It. Both Test-Case and Test-Block use very similar code. Hopefully you saw that a test runner is very simple at its core. This concludes our review of Describe, Context and It. Why should I care That’s a more involved question if you’re new to DevOps in general. It provides a language that allows you to define test cases, and the Invoke-Pester cmdlet to execute these tests and report the results. Pester provides a framework for running Unit Tests to execute and validate PowerShell commands inside of PowerShell.Pester follows a file naming convention for naming tests to be discovered by pester at test time and a simple set of functions that expose a Testing DSL for isolating, running, evaluating and reporting the results of Powershell commands. I like to use the ForEach method as it is slightly quicker than other methods. Pester is a test framework for PowerShell. Function Assert-Equal ( $Expected, $Actual ) The problem with Test Cases is that we can only easily loop through one collection, but as Pester is just PowerShell we can simply use ForEach if we wanted to loop through multiple ones, like instances and then databases.