Custom Service Resource

DSC
1

My environment has a security requirement that requires we configure particular services as Disabled or Automatic. Using a database of this information we are testing configuring these with DSC. In order to automate this we have a DSC Resource class for services that will be used to ignore services that are not installed on a particular node. What we have written works just fine with configuring the services but doesn’t always succeed when using Test-DSCConfiguration or Get-DSCConfiguration. From one check to the next it will work okay, or fail with the error:

Get-DscConfiguration : The PowerShell DSC resource '[customService]AppMgmt' with SourceInfo 'C:\DSC\config.ps1::141::13::customService' threw one or more non-terminating errors while running the Get functionality. 
These errors are logged to the ETW channel called Microsoft-Windows-DSC/Operational. Refer to this channel for more details.
At line:1 char:1
+ Get-DscConfiguration
+ ~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (MSFT_DSCLocalConfigurationManager:root/Microsoft/...gurationManager) [Get-DscConfiguration], CimException
    + FullyQualifiedErrorId : NonTerminatingErrorFromProvider,Get-DscConfiguration

Here is the resource code. Please let me know if any additional information will help as the event logs mentioned just repeat the error given above. Also, any assistance on how better to approach this would be welcome.

Enum StartupType
{
    Automatic
    Disabled
    Manual
}

Enum Status
{
    Running
    Stopped
    Ignore
}


[DscResource()]
Class customService
{
    
    [DscProperty(Key)]
    [String]$Service

    
    [DscProperty(Mandatory)]
    [StartupType]$StartupType

    
    [DscProperty(Mandatory)]
    [Status]$Status

    
    [void] Set()
    {
        $ServiceExist = $this.ServiceExist($this.Service)

        If ($ServiceExist)
        {
            $this.SetService()
        }
        Else
        {
            Write-Verbose "$($this.Service) not available. Set skipped."
        }
    }

    
    [bool] Test()
    {
        $ServiceExist = $this.ServiceExist($this.Service)

        If ($ServiceExist)
        {
            Write-Verbose "Found $($this.Service)."
            $Configured = $this.TestService($this.Service,$this.StartupType.ToString(),$this.Status)
            If ($Configured)
            {
                Return $true
            }
            Else
            {
                Return $False
            }
        }
        Else
        {
            Write-Verbose "Did not find $($this.Service). Skipped"
            Return $true
        }
         
    }

    
    [customService] Get()
    {
        Return $this
    }

    
    [bool] ServiceExist([string]$Service)
    {
        $Present = Get-Service -Name $Service -ErrorAction SilentlyContinue
        
        If ($Present)
        {
            Return $true
        }
        Else
        {
            Return $false
        }
    }

    
    [bool] TestService([string]$Service,[string]$StartType,[string]$State)
    {
        $ServiceInfo = Get-WmiObject -Class Win32_Service -Filter "Name='$Service'" -ErrorAction SilentlyContinue

        If ($State -eq 'Ignore')
        {
            $State = $ServiceInfo.State
            Write-Verbose "Service is listed as Ignore - Testing for $($ServiceInfo.State)"
        }

        If ($ServiceInfo.StartMode -eq $StartType -and $ServiceInfo.State -eq $State)
        {
            Return $true
        }
        Else
        {
            Return $false
        }
    }

    
    [void] SetService()
    {
        If (-not $this.ServiceExist($this.Service))
        {
            Write-Verbosek "$($this.Service) is not found. Set skipped"
        }
        Else
        {
            Write-Verbose "Setting $($this.Service) to $($this.StartupType) - $($this.Status)"

            If ($this.StartupType -eq [StartupType]::Disabled)
            {
                Write-Verbose "Stopping $($this.Service)."
                Stop-Service -Name $this.Service -WarningAction SilentlyContinue
            }

            If ($this.Status -eq 'Ignore')
            {
                Set-Service -Name $this.Service -StartupType $this.StartupType.ToString()
            }
            Else
            {
                Set-Service -Name $this.Service -StartupType $this.StartupType.ToString() -Status $this.Status
            }
        }
    }

}
2

You’re going to have to add some logging and debug code to your class, so you can log what it’s about to try and then catch and log any errors. Just staring at the code, I can’t really point to a definite problem.