Write Your first Pester Test Today

I was in Glasgow this Friday enjoying the fantastic hospitality of the Glasgow SQL User Group @SQLGlasgow and presenting sessions with Andre Kamman, William Durkin and Chrissy LeMaire

I presented “Green is Good Red is Bad – Turning your checklists into Pester Tests”. I had to make sure I had enough energy beforehand so I treated myself to a fabulous burger.

20171110_114933-compressor.jpg

Afterwards I was talking to some of the attendees and realised that maybe I could show how easy it was to start writing your first Pester test. Here are the steps to follow so that you can  write your first Pester test

Decide the information you wish to test
Understand how to get it with PowerShell
Write a Pester Test

The first bit is up to you. I cannot decide what you need to test for on your servers in your environments. Whatever is the most important. For now pick one thing.

Logins – Lets pick logins as an example for this post. It is good practice to disable the sa account is advice that you will read all over the internet and is often written into estate documentation so lets write a test for that

Now we need the PowerShell command to return the information to test for. We need a command that will get information about logins on a SQL server and if it can return disabled logins then all the better.

As always when starting to use PowerShell with SQL Server I would start with dbatools if we run Find-DbaCommand we can search for commands in the module that support logins. (If you have chosen something none SQL Server related then you can use Get-Command or the internet to find the command you need)

find-dbacommand.png

Get-DbaLogin . That looks like the one that we want. Now we need to understand how to use it. Always always use Get-Help to do this. If we run

we get all of the information about the command and the examples. Example 8 looks like it will help us

get-dbalogin example

So now try running the command for our disabled sa account

disabled sa account

So we know that if we have a disabled sa account we get a result. Lets enable the sa account and run the command again

not disabled.png

We don’t get a result. Excellent, now we know what happens for a successful test – we get one result and for failed test we get zero results. We can check that by running

login count

The first one has the account disabled and the second one not. So now we can write our Pester Test. We can start with a Describe Block with a useful title. I am going to add a context block so that you can see how you can group your tests.

describe context

and then we will write our test. Pester Tests use the It keyword. You should always give a useful title to your test

it should

Now we can write our test. We know that the command returns one result when we want it to pass so we can write a test like this

login test.png

The code I have added is

which is
  • the code for getting the information about the thing we wanted to test (The count of the disabled sa logins on the instance)
  • a pipe symbol |
  • The Should key word
  • The Be keyword
  • and the result we want to pass the test (1)

Ta Da! One Pester test written. You can run the test just by highlighting the code and running it in VS Code (or PowerShell ISE) and it will look like this for a passing test

passing test

It is better to save it for later use and then call it with Invoke-Pester

invoke

So now you can write your first Pester test. Just find the PowerShell to get the information that you need, understand what the results will be for passing and failing tests and write your test 🙂

Using Plaster To Create a New PowerShell Module

Chrissy, CK and I presented a pre-con at PASS Summit in Seattle last week

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Tracey Boggiano T | B came along to our pre-con and afterwards we were talking about creating PowerShell modules. In her blog post she explains how she creates modules by copying the code from another module (dbatools in this case!) and altering it to fit her needs. This is an absolutely perfect way to do things, in our pre-con we mentioned that there is no use in re-inventing the wheel, if someone else has already written the code then make use of it.

I suggested however that she used the PowerShell module Plaster to do this. We didnt have enough time to really talk about Plaster, so Tracy, this is for you (and I am looking forward to your blog about using it to 😉 )

What is Plaster?

Plaster is a template-based file and project generator written in PowerShell. Its purpose is to streamline the creation of PowerShell module projects, Pester tests, DSC configurations, and more. File generation is performed using crafted templates which allow the user to fill in details and choose from options to get their desired output.

How Do I Get Plaster?

The best way to get Plaster is also the best way to get any PowerShell module, from the PowerShell Gallery

You can just run

If you get a prompt about the repository not being trusted, don’t worry you can say yes.

Following PowerShell’s Security Guiding Principles, Microsoft doesn’t trust its own repository by default. The advice as always is never trust anything from the internet even if a bearded fellow from the UK recommends it!!

The PowerShell Gallery is a centralised repository where anyone can upload code to share and whilst all uploads are analyzed for viruses and malicious code by Microsoft, user discretion is always advised. If you do not want to be prompted every time that you install a module then you can run

if you and/or your organisation think that that is the correct way forward.

What Can We Do With Plaster?

Now that we have installed the module we can get to the nitty gritty. You can (and should) use Plaster to automate the creation of your module structure. If you are going to something more than once then automate it!

I created a repository for my Plaster Template You are welcome to take it and modify it for your own needs. I created a folder structure and some default files that I always want to have in my module folder

module framework.png

So in my template I have created all of the folders to organise the files in the way that I want to for my modules. I have also included the license file and some markdown documents for readme, contributing and installation. If we look in the tests folder

tests folder.png

There are some default test files included as well.

But Plaster is more than just a file and folder template repository, if we look in the installation markdown file,  it looks like this

We can paramatarise the content of our files. This will create a very simple markdown showing how to find and install the module from the PowerShell Gallery which saves us from having to type the same thing again and again. Lets see how to do that

The Manifest XML file

The magic happens in the manifest file You can create one with the New-PlasterManifest command in the template directory

This will create a PlasterManifest.xml file that looks like this
You can see that the parameters and content tags are empty. This is where we will define the parameters which will replace the tokens in our files and the details for how to create our module folder.

Plaster Parameters

At present my parameters tag looks like this
So we can set up various parameters with their names and data types defined and a prompt and if we want a default value.
We can then use
in our files to make use of the parameters.

Plaster Content

The other part of the manifest file to create is the content. This tells Plaster what to do when it runs.

Mine is split into 3 parts

We can provide messages to the user with the message tag. I create the folders using the filesource tag
This part creates all of the required files. You can see that the static files (those which do not require any sort of parameterisation for the contents use the same file source tag as the folders with the source defined. The files that have content which is parameterised use a tag of templateFile Source telling Plaster to look inside there for the tokens to be replaced.
The last part of the content creates the module manifest.
which I have filled in with the parameters for each of the values.

Creating a new module at the command line

Now you can easily create a module with all of the required folders and files that you want by creating a directory and running

which looks like this

Its that easy 🙂

Create a module without prompts

You can also create a module without needing to answer prompts. We can prefill them in our parameter splat
Which will look like this

Make Your Own

Hopefully this have given you enough information and shown you how easy it is to automate creating the framework for your new PowerShell modules and parameterising them. Let me know how you get on and share your examples

Further Reading

Kevin Marquettes blog post is an excellent and detailed post on using Plaster which you should also read for reference as well as David Christians post which has some great content on adding user choice to the parameters enabling one plaster template to fulfill multiple requirements.

dbatools with SQL on Docker and running SQL queries

I had a question from my good friend Andrew Pruski dbafromthecold on twitter or SQL Container Man as I call him 🙂

How do you guys run SQL Commands in dbatools

I will answer that at the bottom of this post, but during our discussion Andrew said he wanted to show the version of the SQL running in the Docker Container.

Thats easy I said. Here’s how to do it

You need to have installed Docker first see this page You can switch to using Windows containers right-clicking on the icon in the taskbar and choosing the command. If you have not already, then pull the SQL 2017 SQL image using

This may take a while to download and extract the image but its worth it, you will be able to spin up new SQL instances in no time

You can create a new SQL Docker container like this


In only a few seconds you have a SQL 2017 instance up and running (Take a look at Andrews blog at dbafromthecold.com for a great container series with much greater detail)

Now that we have our container we need to connect to it. We need to gather the IPAddress. We can do this using docker command docker inspect but I like to make things a little more programmatical. This works for my Windows 10 machine for Windows SQL Containers. There are some errors with other machines it appears but there is an alternative below


Those two lines of code (and several lines of comments) puts the results of the docker inspect command into a variable and then uses regex to pull out the IP Address

If you are getting errors with that you can also use

Thanks Andrew 🙂

Now we just need our credentials to connect to the instance


and we can connect to our SQL container

and get the version

and many many other properties, just run

to see them. At the bottom, you will see a ScriptMethod called Query, which means that you can do things like


Which looks like

It’s slightly different with a Linux SQL container. Switch Docker to run Linux containers by right-clicking on the icon in the taskbar and choosing the command to switch.
If you haven’t already pull the Linux SQL image

and then create a container


Now we just need to connect with localhost and the port number which we have specified already and we can connect again


Of course, this isn’t restricted just Connect-DbaInstance you can do this with any dbatools commands

Go and explore your Docker SQL conatiners with dbatools 🙂

You can get it using

and find commands with

Don’t forget to use Get-Help with the name of the command to get information about how to use it

Enjoy 🙂

A Pretty PowerBi Pester Results Template File

I have left the heat and humidity of Singapore where I have been presenting at the PowerShell Conference Asia and DevOpsDays Singapore to travel to Seattle for PASS Summit. During my Green is Good – Red is Bad session someone asked me if the PowerBi that I showed at the end would work with any Pester Test Results object and I said (without thinking) that it would.

It turns out that the PowerBi that I had set up for that session will work with my function to run Pester Tests against an Ola Hallengren installation but some of the formatting and custom columns were specific to that test.

I said that I would share a Power Bi file that people could plug any Pester Test Results into. This is the first iteration of that. I doubt that it will work for every single test but I think it will be a good starting point for people to use.

This is how to use it

Download the file from here.

Run your Pester Tests using the PassThru Parameter and set the results to a variable, you can also use the Show Parameter to reduce the output of the tests to the screen (and also speed up the tests)

Then we convert the $PesterResults object into a JSON file

Open the Power Bi file you downloaded

Click Home

then the words “Edit Queries”

then data source settings,

highlight the filename and click change source

then navigate to the JSON file you just created, click ok and close and the apply changes.

Which will load the data from the JSON file and display your pester results. You can then save this file with a new name and keep the template for other tests.

It’s not going to be perfect

It’s not going to work in all circumstances and I expect that with some test results it will display the results in a less than optimal manner but you should be able to modify this to suit your needs.

Please give it a try and see how you get on

Here is a sample report created with Demo 1 from my Green is Good session

You can click around and change the data you can see and also look at the other 4 pages

Here is another one that I created using my dbatools-scripts repo and a config file. Again, have a click around and see what it does.

 

I also created a quick video showing the process too which I will upload when I am not at 35000 feet!!

Enjoy 🙂 Also, let me know if you think it would be better to have the file in Github which would allow contributions but it would only be seen as a binary file and therefore merging will be difficult. I am happy to do so.

TSQL2sDay – Get-PostRoundup

First an apology, this round up is late!

The reason for that is an error in the PowerShell testing module Pester (That’s not completely true as you shall see!!)

I spoke in Stuttgart at the PowerShell Saturday last weekend and had intended to write this blog post whilst travelling, unfortunately I found a major error in Pester (again not strictly true but it makes a good story!!)

I explained it with this slide in my presentation

Yep, I forgot to pack my NUC with my VMs on it and had to re-write all my demos!!

But anyway, on to the TSQL2sDay posts

What a response. You wonderful people. I salute you with a Rimmer salute

There are 34 TSQL2sDay posts about dbatools, about starting with PowerShell, If you should learn PowerShell, SSAS, SSRS, Log Shipping, backups, restores, Pester, Default settings, best practices, migrations, Warnings in Agent Jobs, sqlpackage, VLFs, CMS, Disabling Named Pipes, Orphaned users, AG Status, AG Agent Jobs, logging, classes, auditing, copying files, ETL and more.

I am really pleased to see so many first timers to the TSQL2sDay blog monthly blog party. Please don’t let this be your only TSQL2sDay post. Come back next month and write a post on that topic.

Here they are below in the media of tweets, so that you can also go and follow these wonderful people who are so willing to share their knowledge. Say thank you to them, ask them questions, interact.

Learn, Share, Network

Volker wrote about testing best practices with dbatools

Dave explains why PowerShell is so useful to him in his ETL processes

Steve writes about the time he has saved using PowerShell to automate restores and audit SQL Server instances

Nate talks about copying large files like SQL Server backups using BITS with PowerShell

Warren talks about his experience as a beginner, the amount of things he automates and his DBReboot module

THANK YOU every single one and apologies if I have missed anyone!

 

 

#TSQL2sDay – Starting Out with PowerShell

tsql2sdayThis months TSQL2sday is hosted by me!

Surprise! – I chose PowerShell

I am really looking forward to seeing what other people post. Some advanced scripts that will help you and show you how you can use PowerShell to save you time and hopefully some beginner posts explaining experiences or showing you how to start with PowerShell and SQL Server. I decided to go with the latter.

First though a warning.

PowerShell is another language, you are not going to be as proficient in a new language as you are in the language you spend all day working with. You will have to go through the learning curve and you will have to understand how to interpret errors. There is a learning curve just like with any language. Undoubtedly you will get frustrated at times. Reach out for help. Use twitter, use the #powershellhelp in the SQL Server Community Slack channel. There are many other places and plenty of people who will be glad to help you.

Open the Editor

If you are using a Windows machine you will have PowerShell installed. You will find it in your start menu on Windows 7 under All Programs, Accessories, Windows PowerShell folder, and then click Windows PowerShell or Windows PowerShell ISE. On Windows 8 or 10 search for PowerShell.

PowerShell or PowerShell ISE? Use PowerShell instead of cmd.exe for command line usage and ISE for developing scripts, functions and modules. (However, read on before making your choice)

PowerShell on Other O/S’s (and Windows!)

Just as SQL Server is available on Linux PowerShell is also available cross-platform, you can run and edit PowerShell on Linux and on Mac natively. The best editor to use is VS Code which is also available cross-platform. In fact, as Microsofts David Wilson says in this blog post

The PowerShell ISE has been the official editor for PowerShell throughout most of the history of Windows PowerShell. Now with the advent of the cross-platform PowerShell Core, we need a new official editor that’s available across all supported OS platforms and versions. Visual Studio Code is now that editor and the majority of our effort will be focused there.

So my advice is, whichever operating system you are using, use VS Code to write, edit, debug and run your PowerShell as that is the editor where Microsoft are spending the majority of their effort in development. Follow the instructions here to install You can also use it with many other languages including T-SQL. I find it a very useful tool

Where to start?

Well that depends what you want to do. Start by reading. Start by trying to accomplish something in PowerShell even if you know how to do it another way. This will also help you to realise when you are trying to use a hammer to put in a screw (using the wrong tool for the job)

What Command?

You don’t know where to start so how do you know the command to use? Here is a first command. You will use it often. I use it everyday still despite using PowerShell daily for many years. But don’t run it yet!

PowerShell is quite intuitive in it’s command naming. It uses a Verb-Noun syntax. You know without me explaining what this command will do. It will “Get” the “Command” (s). PowerShell uses singular nouns for its commands. I have 8000+ commands on my machine so it would have overloaded you with commands if you had run it without filters!

We use * as a wildcard in PowerShell so we can use that with our Get-Command command to find some commands to run. Type Get-Com and then hit the tab button. This will not only help you as it will auto-complete, it will reduce the number of errors as it will only auto-complete correct command names :-).

This will show all commands which end with service. The results will have some different headings. The screenshot below shows just one command to reduce confusion.

03 - get-service.png

The type of command, the name of the command, the version of the command and the module it is in. PowerShell uses modules to group commands together and to enable you to install the ones that you require from a repository like the PowerShell Gallery (more on this later).

You can find all of the commands in a module with the Get-Command command like this

This will show you all of the commands in the management module which may be a good place to start exploring. In this module for example

  • Test-Connection is like ping but better
  • Test-Path tests the existence of files and file paths
  • *-Service works with services
  • *-Process works with processes
  • *-Computer for power options for a computer
  • Get-ComputerInfo which will give you computer information (surprisingly 🙂 )

This is also something to remember in the future when you want to know what commands a module has or what the precise name of the command is.

Maybe once you install the dbatools module, the sqlserver module or the SSRS module??

HOMEWORK – Examine the names of commands in other modules that you find in

or for more choices

How do I use that command though?

You need to read! PowerShell comes with a lot of documentation, a lot of it is available on your machine. Lets introduce another command

As you can imagine, this gets the help for a command or returns help topics about PowerShell. Again, I use this every single day and you should too. Lets start with the first one. Lets get help for the Get-ChildItem command

Now, some of you may not get very much returned and a message at the bottom which says

Get-Help cannot find the Help files for this cmdlet on this computer. It is displaying only partial help.
— To download and install Help files for the module that includes this cmdlet, use Update-Help.
— To view the Help topic for this cmdlet online, type: “Get-Help Get-ChildItem -Online” or
go to https://go.microsoft.com/fwlink/?LinkID=113308.

When you have something else to do I would recommend running Update-Help as it suggests (It can take a few minutes to run) but for now make use of the -Online switch.

HOMEWORK – Run Update-Help

This is available for all of the Microsoft modules and some of the better open source modules, dbatools is an example of a (brilliant) community module which has -Online URLs for it’s commands. Running Get-Help (with or without the -Online switch) will give you plenty of information about the command, the switches available, the inputs and outputs.

Maybe start by using the -examples switch

will show you some examples of how to use the command

05 gethelp examples

Now you can start to explore the file system with this command (also the SQL Server, Registry, Certificate Store and many more things)

I also like to use the ShowWindow switch

which will open up the help in a separate window which can be useful when you are writing a script and it is searchable

04 - gethelp showwindo

But Chrissy prefers to use the -Detailed switch

You can decide which way you like best.

Now you know how to find a command and hot to find out how to use it. If you are using VS Code (or ISE) you have access to Intellisense and snippets to help you with the syntax. You can run a command and get some results.

HOMEWORK – Use Get-Help to understand how to use commands. ( Extra merit marks for teachers pets who read the topics they find using Get-Help About_*) Also, instant demerit points throughout the course (your career) for students who do not use Get-Help when using any command for the first time.

Hopefully you are confident enough to have run some commands. If you are worried about breaking things only run the commands which start with Get- as these should only be returning information or objects and not changing anything.

This isn’t cmd 

This isn’t cmd. What you are getting back is not text.

It is an object.

Unless you choose to use one of the formatting commands or the command you are using outputs using a formatting command (pro-tip don’t do that) then what you will receive as the results of your command is an object.

This means that there is more that you can do with the results than just have them in text format. You want Text File,JSON, XML, CSV, Excel output or to write to a database? Look here for ideas

Objects,Objects,Objects

Objects are awesome. Lets start with a SQL Server Instance object to show you how to explore objects. You will need to install the most useful PowerShell module you will find if you are working with SQL Server – dbatools

Disclosure – I am a contributor to the open source module dbatools. I am presenting a full day workshop in Singapore for the PowerShell Conference Asia in October. I am also proctoring at Chrissy and CK’s PASS Summit in Seattle. I highly recommend that you come and join us at one of those events if you can to further learn how you can use PowerShell to administer SQL Server

You can install it from the PowerShell Gallery using

You will be asked if you want to trust the repository, say Yes. If this doesn’t work on your machine (you are on an older version of PowerShell) follow the instructions on this page.  Or ask for help in #powershellhelp in Slack

Now that the module is installed we can create a SQL Server Instance object by assigning the results of a command to a variable.

A variable in PowerShell is designated by a $.

I suggest that you get used to following this step as well. This is a great way of exploring the results of any command and understanding what you can do with it.

We will use the Get-Member command. Another one that I use every single day.

Warning – You do not have to use these methods to accomplish tasks in PowerShell against SQL Server as both Microsoft and the community have released modules which will enable you to general tasks without “coding”

This is an example to get you comfortable with PowerShell by using a target that you are comfortable with and can recognise.

Now that we have an object we can explore it

By just calling the variable it will display the default properties

06 - default properties.png

If you want to see what else is available you can use Get-Member You just pipe | to Get-Member

This will show you all of the events, methods and properties available on the object.  Methods are really useful, enabling you to do things like start agent jobs or enumerate permissions or members

If you wish to see all of the processes that are running on the instance

Out-GridView is a useful command allowing you to see the results of your command in a graphical format and easily filter using the search bar at the top.

07 - ogv.png

Other things you can do include reading the errorlog

08 - errorlog.png

Get the connections to a database

Get the current Traceflags

The properties that are available at this level are similar to the view that you see in SSMS Object Explorer for the instance. You can see a databases folder in SSMS and you can expand it. You can do the same in PowerShell

That is going to just show you the names of the databases on that instance. You can do the same thing using the pipe | again and Select-Object

This will pass the Databases array of objects “along the pipeline” and then you can use Select-Object to choose them. Multiple properties can be chosen with commas.

09 - databases.png

PowerShell will let you select things that do not exist so for example

does not return an error but some of the columns are empty 🙂 You need to use the names of the properties returned from Get-Member in your Select statement (Hmm, sounds a bit like T-SQL)

18 select.png

You can look at a single database default properties using

You can then use Get-Member to explore deeper and deeper.

You can also look at the Agent from the instance level object

HOMEWORK – Using the code above explore the $SMO object, look at the databases, tables, the columns and the indexes. Explore other properties and select them. (Extra merit points for exploring the SQL Server like a file system using the SQLServer drive. Start with cd SQLSERVER:\ and use Get-ChildItem or its alias dir or ls)

Warning Reminder – You do not have to use these methods to accomplish tasks in PowerShell against SQL Server as both Microsoft and the community have released modules which will enable you to do general tasks without “coding”

But this is a very useful way of understanding and exploring using PowerShell with a type of object that you understand. You will use these methods all of the time and when you need to accomplish the next thing you have the tools. Already. Now.

Recap

You should take from this for the future

  • Get-Command *search* – Find a Command
  • Get-Help NameOfCommand – How do I use the Command ?
  • $var = Some Command here – Set the output of a command to a variable
  • $var | Get-Member – What Events, Methods, Properties do I have on this object
  • $var | Select Property1, Property2, Property3

That’s All Code – Where’s The Easy Buttons ?

There are two answers to this.

Firstly, yes it’s all code, but you will find that code is the future. Every time you run the same piece of code it will do the same thing, every time a junior DBA follows the steps to manually do something in a GUI like SSMS they may make a mistake and a different mistake each time. As DBAs we use stored procedures, views, functions and more, they are all code. Using code is vital for automation, for making things easy, for reducing the risk of mistakes, for getting rid of the mundane.

It is also required for DevopsAgileScrumContinuousIntegrationDeliveryWhatsTheNextBuzzWord which is all the rage (and also a lot of fun with interesting challenges)

As estates get bigger and bigger the GUI becomes less useful to you.

Secondly, remember my warning at the top of this post? There is no easy button. You will have to learn new things you will make mistakes and get errors, you need to ask for help

I Have An ERROR !

Don’t be disheartened, errors happen. The red text looks scary and frightening but its not.

Read the Error

Lets use Microsofts sqlserver module. There are all sorts of ways to get it. If you have SSMS you probably have it already. Lets check

A result like this means that you have it

10 - get-module.png

If not

Again you will be asked if you want to trust the repository, say yes!

If I run

I get

11 - error.png

That error is fairly easy to understand. I can’t connect to an instance that isn’t running

If I run

I get a different error

12 sql login error.png

The Get-SqlLogin from Microsofts sqlserver module returns an error if it cannot find the specified login name. The important part of this error message is ObjectNotFound. That tells us what has happened

If we look at the logins

13 - Logins.png

and choose one that exists everything is good

14 one login.png

HOMEWORK – Here is another object to explore with Get-Member. Explore the Login object

For example

15 - login script.png

But back to errors. Sometimes it isn’t quite so obvious. I have altered my Create-Database function so that it shows an error instead of a helpful message.

16 - db error.png

This is an example of the sort of error message that you might not be able to decipher so easily. Even if you read the message it says Exception calling .ctor with 2 arguments. How can you, as a new PowerShell user work out what has happened?

Objects

Remember, PowerShell is great because of objects? The errors are objects too. Lets have a look at the error in full. This is another piece of code that I still use every single day

The $error variable holds an array of error objects for that session. The [0] targets the 1st object in the array which is the latest. We pipe that to fl which is an alias for Format-List. Normally I am very clear about not using aliases in my blog posts as I believe that you should not use aliases in your scripts and functions (This is due to a bad experience trying to google for % to find out what it was in PowerShell many years ago). However, you are only going to use this at the command line so its ok.

The results are

17 error.png

Once you read the error, you will see that there is a generic connection failed error message which you will be used to seeing and now you can go about fixing it.

Errors aren’t scary. You just have to read them. Sometimes you have to expand them to read them. Once you have read them don’t forget that there is also a lot of help out there on the internet. I recommend the #powershellhelp channel in the slack but with the full error message you will be able to get some useful results from whatever your choice of helpful solutions is.

That’s exactly 3000 words – which is slightly (!) more than I intended to write and a lot to read, so if you have got all the way down here. Congratulations, when you see me at Summit or at a SQL Saturday come up and tell me and I will give you a special sticker 🙂

Hopefully this has given you some guidance to starting to use PowerShell with SQL and how you can help yourself.

Good luck.

Automatically updating the version number in a PowerShell Module – How I do regex

I am presenting Continuous Delivery for your PowerShell Module to the PowerShell Gallery at PSDayUK in London. Go and register if you will be close to London on Friday 22nd September.

In 45 minutes we will

– Use Plaster to create our module framework
– Use GitHub for Version Control
– Use Pester to develop our module with TDD
– Use VSTS to Build, Test (with Pester) and Release our changes to the PowerShell Gallery

45 minutes will not give me much time to dive deep into what is done but I will release all of my code on GitHub.

One of the things I needed to accomplish was to update the version number in the module manifest file. I did this with some regex and this is how I achieved it.

I went to regex101.com and pasted in the contents of a module file into the test string box and start to work out what I need. I need the value after ModuleVersion = ‘ so I started like this

01 - regex101.png

Under the quick reference it has some explanations which will help you. Keep going until you have the correct value in the match information. In the image below you can see that it has a Group 1 in green which matches the value I want (0.9.13). There is also an explanation of how it has got there. This is what I shall use in the PowerShell script

01 - regex.png

Now we can go to PowerShell. First get the contents of the file

Then we use [regex]::matches() to get our value as shown below. I always like to write in the comments what the regex is doing so that I (or others) know what was intended. We also set the value to a type of Version. I reference the group 1 value that I saw in the website.

Next we need to add one to the version number

and then replace the value in the file, notice the Get-Content has braces around it

That’s how I do it and the process I use when I need regex!

Here is the full script

 

An easier way

My fabulous friend and MVP Ravikanth Chaganti has told me of a better way using Import-PowerShellDataFile

This command is available on PowerShell v5 and above. There is no need to use regex now 🙂 You can just get the manifest as an object and then use the Update-ModuleManifest to update the file