Need to check if 7 specific tags exist on a list of azure VMs - azure

Question

Hello I need to check for if a list of azure VMs have 7 specific tags using PowerShell, the tag values don't need to be checked. If any of the 7 tags are missing then the script will need to write error and print what tags were missing. I can get the tags from
$vmDetails = Get-AzVM -Name $sourceVMName -ResourceGroupName $sourceResourceGroupName
$vmTags = $vmDetails.Tags
Then I can run a loop
foreach ($keyval in $vmtags.keys)
but I am unsure how to do the comparison without a bunch of if statements. I'm sure an array is needed but can't remember what may be best. thanks a bunch.

Answer 1

Assuming the Tags property is a hashtable as you have shown on your code, the code (pseudo code as I don't have a way of testing this) could look like this:
# Get the base Tags needed to compare
$vmDetails = Get-AzVM -Name $sourceVMName -ResourceGroupName $sourceResourceGroupName
# Assuming the Tags property is a Hashtable
$vmTags = $vmDetails.Tags.Keys
# Get the count of Tags
$i = $vmTags.Count
# Get all existing VMs on a Resource Group
$allVMs = Get-AzVM -ResourceGroupName $sourceResourceGroupName
foreach($vm in $allVMs)
{
# Store the Tags of this VM
$thisVMtags = $vm.Tags.Keys
# If the count of Tags of this VMs is not the same as the count of Base Tags
if($thisVMtags.Count -ne $i)
{
# Get the missing Tags of this VM
$missingTags = $vmTags.where({
$_ -notin $thisVMtags
}) -join ', '
# Write a warning with details of this VM Name and the missing Tags
Write-Warning "{0} is missing the following Tags: {1}" -f $vm.Name, $missingTags
}
}