ScriptsToProcess/Resolve-NodeProperty.ps1
|
function Global:Resolve-NodeProperty { [CmdletBinding()] Param( [Parameter( Mandatory, Position = 0 )] $PropertyPath, [Parameter( Position = 1 )] [AllowNull()] $DefaultValue, [Parameter( Position = 3 )] $Node = $ExecutionContext.InvokeCommand.InvokeScript('$Node'), [Alias('DatumStructure')] $DatumTree = $ExecutionContext.InvokeCommand.InvokeScript('$ConfigurationData.Datum'), [Alias('SearchBehavior')] [AllowNull()] $options, [string[]] $SearchPaths, [Parameter( Position = 5 )] [allowNull()] [int] $MaxDepth ) # Null result should return an exception, unless defined as Default value $NullAllowed = $false $ResolveDatumParams = ([hashtable]$PSBoundParameters).Clone() foreach ($removeKey in $PSBoundParameters.keys.where{$_ -in @('DefaultValue','Node')}) { $ResolveDatumParams.remove($removeKey) } # Translate the DSC specific Node into the 'Node' variable and Node name used by Resolve-Datum if($Node) { $ResolveDatumParams.Add('Variable',$Node) $ResolveDatumParams.Add('VariableName','Node') } # Starting DSC Behaviour: Resolve-Datum || $DefaultValue || $null if specified as default || throw if($result = Resolve-Datum @ResolveDatumParams) { Write-Verbose "`tResult found for $PropertyPath" } elseif($DefaultValue) { $result = $DefaultValue Write-Debug "`t`tDefault Found" } elseif($PSboundParameters.containsKey('DefaultValue') -and $null -eq $DefaultValue) { $result = $null $NullAllowed = $true Write-Debug "`t`tDefault NULL found and allowed." } else { #This is when the Lookup is initiated from a Composite Resource, for itself if(-not ($here = $MyInvocation.PSScriptRoot)) { $here = $Pwd.Path } Write-Debug "`t`tAttempting to load datum from $($here)." $ResourceConfigDataPath = Join-Path $here 'ConfigData' -Resolve -ErrorAction SilentlyContinue if($ResourceConfigDataPath) { $DatumDefinitionFile = Join-Path $ResourceConfigDataPath 'Datum.*' -Resolve -ErrorAction SilentlyContinue if($DatumDefinitionFile) { Write-Debug "Resource Datum File Path: $DatumDefinitionFile" $ResourceDatum = New-DatumStructure -DefinitionFile $DatumDefinitionFile } else { #Loading Default Datum structure Write-Debug "Loading data store from $($ResourceConfigDataPath)." $ResourceDatum = New-DatumStructure -DatumHierarchyDefinition @{ Path = $ResourceConfigDataPath } } $ResolveDatumParams.remove('DatumTree') $result = Resolve-Datum @ResolveDatumParams -DatumTree $ResourceDatum } else { Write-Warning "`tNo Datum store found for DSC Resource" } } if($result -or $NullAllowed) { $result } else { throw "The lookup returned a Null value, but Null is not specified as Default. This is not allowed." } } Set-Alias -Name Lookup -Value Resolve-NodeProperty -scope Global Set-Alias -Name Resolve-DscProperty -Value Resolve-NodeProperty -scope Global |