Powershell for Changing AppSettings in Application Configuration File
Here is a PowerShell Function that I created with the objective of changing an application configuration file and then, if we want, restart a service
Function Set-ApplicationSettingConfigProperty
{
param (
[parameter(Mandatory = $true)][ValidateScript ({Test-Path $_})][string] $PathToConfigFile,
[parameter(Mandatory = $true)][string] $PropertyName,
[parameter(Mandatory = $true)][string] $PropertyValue,
[Parameter(Mandatory = $false)][Validatescript ({(Get-Service $_) -ne $null})][string] $NameOfServiceToRestart = $null)
$configurationAppSettingXmlPath = "//configuration/appSettings"
[xml] $configurationDocument = Get-Content $PathToConfigFile
$appSettingsNode = $configurationDocument.SelectSingleNode($configurationAppSettingXmlPath)
if($appSettingsNode -eq $null)
{
$(throw "App Settings Does not Exists! Invalid Configuration File.")
}
$nodeToUpdate = $configurationDocument.SelectSingleNode($configurationAppSettingXmlPath+"/add[@key='$PropertyName']")
if($nodeToUpdate -ne $null)
{
Write-Host "[$PropertyName] Already exists, Removing it to re-set its value."
$removedElement = $appSettingsNode.RemoveChild($nodeToUpdate)
}
Write-Host "Creating new Configuration Node."
$newPropertyNode = $configurationDocument.CreateNode("element", "add","")
Write-Host "Setting Node Attributes."
$newPropertyNode.SetAttribute("key", $PropertyName)
$newPropertyNode.SetAttribute("value", $PropertyValue)
Write-Host "Appending Child to AppSettings."
$appSettingsNode = $configurationDocument.SelectSingleNode($configurationAppSettingXmlPath).AppendChild($newPropertyNode)
Write-Host "Adding new property into the configuration file."
$configurationDocument.Save($PathToConfigFile)
Write-Host "Property was Successfully Updated."
if([string]::IsNullOrWhiteSpace($NameOfServiceToRestart) -eq $false)
{
Write-Host "Service [$NameOfServiceToRestart] was defined.., Restarting it"
Restart-Service -Name $NameOfServiceToRestart
Write-Host "Service was Restarted..."
}
}