Resolve-DSCConfigurationData/Public/Get-DSCConfigurationDataCredentialProvider.ps1

function Get-DSCConfigurationDataCredentialProvider {
    [CmdletBinding()]
    Param(
        [Parameter(Mandatory=$false)]
        [string]
        $Vault,

        [Parameter(Mandatory=$false)]
        [string]
        $SettingsPath,

        [Parameter(Mandatory=$false)]
        [switch]
        $TestVault
    )

    DynamicParam {
        $ProviderNames = @(Get-ConfigurationDataSecretProviderName)
        if($ProviderNames.Count -eq 0){
            $ProviderNames = @("__NoProvidersRegistered__")
        }

        $ParameterAttribute = [System.Management.Automation.ParameterAttribute]::new()
        $ParameterAttribute.Mandatory = $false
        $ParameterAttribute.Position = 0

        $ValidateSetAttribute = New-Object System.Management.Automation.ValidateSetAttribute -ArgumentList (,[string[]]$ProviderNames)
        $Attributes = [System.Collections.ObjectModel.Collection[System.Attribute]]::new()
        $Attributes.Add($ParameterAttribute)
        $Attributes.Add($ValidateSetAttribute)

        $RuntimeParameter = [System.Management.Automation.RuntimeDefinedParameter]::new(
            "Provider",
            [string],
            $Attributes
        )

        $Dictionary = [System.Management.Automation.RuntimeDefinedParameterDictionary]::new()
        $Dictionary.Add("Provider", $RuntimeParameter)
        return $Dictionary
    }

    begin {
        $Provider = [string]$PSBoundParameters["Provider"]
        if([string]::IsNullOrWhiteSpace($Provider)){
            $ProviderNames = @(Get-ConfigurationDataSecretProviderName)
            if($ProviderNames.Count -eq 1){
                $Provider = $ProviderNames[0]
            }elseif($ProviderNames.Count -eq 0){
                throw "No configuration data secret providers are registered."
            }else{
                throw "Provider is required. Registered providers: $($ProviderNames -join ', ')."
            }
        }

        $ResolvedSettingsPath = Resolve-ConfigurationDataProviderSettingsPath -Provider $Provider -SettingsPath $SettingsPath
    }

    process {
        $Settings = @{}
        $SettingsExists = Test-Path -LiteralPath $ResolvedSettingsPath -PathType Leaf
        if($SettingsExists){
            $Settings = Import-PowerShellDataFile -LiteralPath $ResolvedSettingsPath
        }

        $ProviderSettings = @{}
        if($Settings -is [System.Collections.IDictionary] -and $Settings.ContainsKey($Provider)){
            $ProviderSettings = $Settings[$Provider]
        }

        $DefaultVault = ""
        if($ProviderSettings -is [System.Collections.IDictionary] -and $ProviderSettings.ContainsKey("DefaultVault")){
            $DefaultVault = [string]$ProviderSettings.DefaultVault
        }

        if([string]::IsNullOrWhiteSpace($Vault)){
            $Vault = $DefaultVault
        }

        $Vaults = @()
        $GetSecretVaultCommand = Get-Command -Name Get-SecretVault -ErrorAction SilentlyContinue
        if($null -ne $GetSecretVaultCommand){
            if([string]::IsNullOrWhiteSpace($Vault)){
                $Vaults = @(& $GetSecretVaultCommand)
            }else{
                $Vaults = @(& $GetSecretVaultCommand -Name $Vault -ErrorAction SilentlyContinue)
            }
        }

        $TestResult = $null
        $TestError = $null
        if($TestVault -and -not [string]::IsNullOrWhiteSpace($Vault)){
            $TestSecretVaultCommand = Get-Command -Name Test-SecretVault -ErrorAction SilentlyContinue
            if($null -eq $TestSecretVaultCommand){
                $TestError = "Command [Test-SecretVault] was not found."
            }else{
                try {
                    $TestResult = [bool](& $TestSecretVaultCommand -Name $Vault -ErrorAction Stop)
                }
                catch {
                    $TestResult = $false
                    $TestError = $_.Exception.Message
                }
            }
        }

        [PSCustomObject]@{
            Provider = $Provider
            SettingsPath = $ResolvedSettingsPath
            SettingsExists = $SettingsExists
            DefaultVault = $DefaultVault
            RequestedVault = $Vault
            ProviderSettings = $ProviderSettings
            RegisteredVaults = $Vaults
            TestVault = $TestResult
            TestError = $TestError
        }
    }
}