See https://blog.neilsabol.site/post/importing-duo-psmodule-mfa-powershell-module-azure-automation. This snippet demonstrates securely providing Duo integration details to the Duo-PSModule in Azure Automation using encrypted Automation Variables.

Duo-PSModule-Azure-Automation-RunBook-Auth-Example.ps1

# Get Duo integration details from Automation Variables
$duoiKey = Get-AutomationVariable -Name MyDuoiKey
$duosKey = Get-AutomationVariable -Name MyDuosKey
$duoApiHost = Get-AutomationVariable -Name MyDuoHostname
$duoDirID = Get-AutomationVariable -Name MyDuoDirectoryID

# Build the $DuoOrgs hashtable from retrieved Automation Variables
[string]$DuoDefaultOrg = "Personal"
[Hashtable]$DuoOrgs = @{
Personal = [Hashtable]@{
iKey  = [string]$duoiKey
sKey = [string]$duosKey
apiHost = [string]$duoApiHost
directory_key = [string]$duoDirID
}}