DSCUseIdenticalMandatoryParametersForDSC.md

description	Use identical mandatory parameters for DSC Get, Set, and Test TargetResource functions in a resource
ms.date	07/21/2026
ms.topic	reference
title	DSCUseIdenticalMandatoryParametersForDSC

UseIdenticalMandatoryParametersForDSC

Severity Level: Error

Default state: Always enabled

Description

This rule detects if MOF-based Desired State Configuration (DSC) resources have properties declared with Key or Required attributes in a .mof file that aren't present as mandatory parameters in the corresponding functions. These properties must be declared as mandatory parameters in the Get-TargetResource, Set-TargetResource, and Test-TargetResource functions.

All properties with either Key or Required attributes should have matching mandatory parameters in the Get, Set, and Test functions.

Example

Consider the following MOF schema file.

class WaitForAny : OMI_BaseResource
{
    [key, Description("Name of Resource on remote machine")]
    string Name;

    [required, Description("List of remote machines")]
    string NodeName[];
};

Noncompliant

function Get-TargetResource
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [String]
        $Message
    )
}

function Set-TargetResource
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [String]
        $Message,

        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [String]
        $Name
    )
}

function Test-TargetResource
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [String]
        $Message,

        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [String]
        $Name
    )
}

Compliant

function Get-TargetResource
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [String]
        $Message,

        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [String]
        $Name
    )
}

function Set-TargetResource
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [String]
        $Message,

        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [String]
        $Name
    )
}

function Test-TargetResource
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [String]
        $Message,

        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [String]
        $Name
    )
}

Configure rule

This rule is always enabled and isn't configurable. Use one of the following methods to avoid using this rule:

• Create a custom rule configuration file to include only the rules you want or exclude the rules you don't want.
• Add the appropriate rule suppression attributes to your code to suppress the rule for specific code blocks. For more information, see the Suppressing rules section of Using PSScriptAnalyzer.