Enhance Download-WinRMConfigScript.ps1 to support $env:ZabbixProxyIPAddress fallback and improve parameter handling

ConfigWinRMForZabbix/Download-WinRMConfigScript.ps1

@@ -15,8 +15,9 @@
 .PARAMETER ZabbixProxyIPAddress
     Zabbix Proxy IP address to allow through the WinRM firewall rule
     (FWWinRMTrustedHosts in ConfigWinRM.xml). Omit this parameter to be prompted
-    interactively; pass an empty string to skip the prompt and leave the existing
-    value in ConfigWinRM.xml unchanged.
+    interactively (or to fall back to $env:ZabbixProxyIPAddress if that is set); pass
+    an empty string to skip the prompt and leave the existing value in ConfigWinRM.xml
+    unchanged.
 
 .EXAMPLE
     PS> .\Download-WinRMConfigScript.ps1
@@ -27,27 +28,22 @@
     PS> .\Download-WinRMConfigScript.ps1 -ZabbixProxyIPAddress '192.168.10.50'
     Downloads both files and sets FWWinRMTrustedHosts to 192.168.10.50 without prompting.
 
-.EXAMPLE
-    PS> .\Download-WinRMConfigScript.ps1 -ZabbixProxyIPAddress '192.168.10.50' -WhatIf
-    Shows what would be downloaded/changed without actually downloading or modifying
-    anything.
-
 .EXAMPLE
     PS> irm https://s.tslab.cz/ZBXWinRM | iex
-    Runs the script directly from the repo without saving it locally first, prompting
-    interactively for the Zabbix Proxy IP address. To pass -ZabbixProxyIPAddress in the
-    same one-liner, wrap it as a script block instead:
-    PS> iex "& { $(irm https://s.tslab.cz/ZBXWinRM) } -ZabbixProxyIPAddress '192.168.10.50'"
+    Shortest way to run the script directly from the repo without saving it locally
+    first; prompts interactively for the Zabbix Proxy IP address.
 
 .NOTES
     Author:   Petr Štěpán
     Created:  2026-07-21
-    Version:  1.0.0
+    Version:  1.1.0
     Changelog:
         1.0.0 - Initial version
+        1.1.0 - Added $env:ZabbixProxyIPAddress fallback so a plain "irm | iex"
+                one-liner can supply the IP address without "& { ... } -Param" wrapping
 #>
 
-[CmdletBinding(SupportsShouldProcess = $true, ConfirmImpact = 'Medium')]
+[CmdletBinding()]
 param(
     [Parameter(Mandatory = $false, HelpMessage = 'Zabbix Proxy IP address to allow through the WinRM firewall rule. Leave empty to keep the existing value.')]
     [string]
@@ -78,7 +74,7 @@ function Invoke-RemoteFileDownload {
     .PARAMETER OutFile
         Local destination file path.
     #>
-    [CmdletBinding(SupportsShouldProcess = $true)]
+    [CmdletBinding()]
     param(
         [Parameter(Mandatory = $true)]
         [ValidateNotNullOrEmpty()]
@@ -91,7 +87,6 @@ function Invoke-RemoteFileDownload {
         $OutFile
     )
 
-    if ($PSCmdlet.ShouldProcess($OutFile, "Download from $Uri")) {
     try {
         Invoke-WebRequest -Uri $Uri -OutFile $OutFile -UseBasicParsing
         Write-Host "Downloaded '$Uri' to '$OutFile'."
@@ -100,7 +95,6 @@ function Invoke-RemoteFileDownload {
         Write-Error "Failed to download '$Uri' to '$OutFile': $_"
         throw
     }
-    }
 }
 
 function Update-WinRMTrustedHostConfig {
@@ -112,7 +106,7 @@ function Update-WinRMTrustedHostConfig {
     .PARAMETER TrustedHost
         Value to write into <FWWinRMTrustedHosts>.
     #>
-    [CmdletBinding(SupportsShouldProcess = $true)]
+    [CmdletBinding()]
     param(
         [Parameter(Mandatory = $true)]
         [ValidateScript({ Test-Path -Path $_ -PathType Leaf })]
@@ -137,12 +131,10 @@ function Update-WinRMTrustedHostConfig {
             throw "Element <FWWinRMTrustedHosts> was not found in '$Path'."
         }
 
-        if ($PSCmdlet.ShouldProcess($Path, "Set FWWinRMTrustedHosts to '$TrustedHost'")) {
         $xml.ConfigWinRM.Options.FWWinRMTrustedHosts = $TrustedHost
         $xml.Save($Path)
         Write-Host "FWWinRMTrustedHosts set to '$TrustedHost' in '$Path'."
     }
-    }
     catch {
         Write-Error "Failed to update '$Path': $_"
         throw
@@ -152,20 +144,28 @@ function Update-WinRMTrustedHostConfig {
 # --- Main --------------------------------------------------------------
 try {
     if (-not (Test-Path -Path $DestinationPath)) {
-        if ($PSCmdlet.ShouldProcess($DestinationPath, 'Create directory')) {
         New-Item -Path $DestinationPath -ItemType Directory -Force | Out-Null
         Write-Host "Created directory '$DestinationPath'."
     }
-    }
 
     Invoke-RemoteFileDownload -Uri "$SourceBaseUri/ConfigWinRM.ps1" -OutFile $ScriptFile
     Invoke-RemoteFileDownload -Uri "$SourceBaseUri/ConfigWinRM.xml" -OutFile $ConfigFile
 
-    # Only prompt when the caller did not pass the parameter at all - an explicit empty
-    # string ("") means "skip the prompt, leave ConfigWinRM.xml unchanged".
+    # Only fall back to the environment variable / prompt when the caller did not pass
+    # the parameter at all - an explicit empty string ("") means "skip the prompt,
+    # leave ConfigWinRM.xml unchanged". $env:ZabbixProxyIPAddress lets a plain
+    # "irm <url> | iex" one-liner supply a value without needing "& { ... } -Param" -
+    # piping into iex runs the downloaded param() block as a plain statement with no
+    # bound arguments, so -ZabbixProxyIPAddress itself can only be set that way when
+    # the script is invoked as a real command (locally or via "& { ... }").
     if (-not $PSBoundParameters.ContainsKey('ZabbixProxyIPAddress')) {
+        if ($env:ZabbixProxyIPAddress) {
+            $ZabbixProxyIPAddress = $env:ZabbixProxyIPAddress
+        }
+        else {
             $ZabbixProxyIPAddress = Read-Host -Prompt 'Enter Zabbix Proxy IP address (press Enter to keep the current value)'
         }
+    }
 
     if ([string]::IsNullOrWhiteSpace($ZabbixProxyIPAddress)) {
         Write-Host 'No Zabbix Proxy IP address provided - ConfigWinRM.xml left unchanged.'