Advanced Windows PowerShell Scripting Video Training

Advanced Windows PowerShell Scripting Video Training
Advanced Windows PowerShell Scripting Video Training

Wednesday, October 12, 2016

Using Start-Job with Azure

Today I am like a kid playing with Legos. I’m prepped and ready for the PowerShell Conference in Asia so I’m working on Plan B.  Wait, what?  I just said that I was prepped and ready.  I am, but that does not mean that I am going to rest.  I am delivering a workshop on learning PowerShell, but we are using the attendee’s local computer.  My Plan B is to provide everybody with a virtual environment to play in for the day using Azure. 

My goal is to take everyone’s email address and create a VM in Azure for them.  I want to provision them live.  The problem with this is that if I do sequentially, it will take more than 4 hours to complete.  So, it is time to use background jobs.  When done sequentially, the task completes without any problems.  When performed using Start-Job, my Azure credentials are not passed into the ScriptBlock parameter of Start-Job.  

Azure team member Mark Cowlishaw published a fix for this issue on GitHub.  Here is his solution:

$path = ".\profile.json"
$deploy = {
    Select-AzureRmProfile -Path $path
    Get-AzureRMResourceGroup
}

Save-AzureRmProfile -Path $path

$job = Start-Job -ScriptBlock $deploy
Wait-Job $job
Receive-Job $job

To show you how to use it in practice, here is my test code to remove all of the Azure resources that each test run creates.

$path = "$env:USERPROFILE\documents\WindowsPowerShell\profile.json"
$Number = 18

For ($X = 0 ; $X -lt $Number + 1; $X++)
{
    $name = "NC"+$X
    Start-Job -ArgumentList $Name, $Path `
              -Name $Name `
              -ScriptBlock {
    Param ($Name, $Path)
    Select-AzureRmProfile -Path $path
    Get-AzureRMResourceGroup
    Remove-AzureRmResourceGroup -Name $Name -Force -Verbose
    }
}


A slightly different implementation than what Mark proposed, but only because some of my code is very large.  In short, it works.  I am about to take a sequential 4 hour + build of the Virtual Machines and reduce this task to about 16 minutes with background jobs.


I may just have an awesome opening demonstration of automation at the beginning of my presentation.  See you all next week from Singapore!

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