Source/Public/Get-Node.ps1
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Using NameSpace System.Management.Automation.Language <# .SYNOPSIS Get a node .DESCRIPTION The Get-Node cmdlet gets the node at the specified property location of the supplied object graph. .EXAMPLE # Parse a object graph to a node instance The following example parses a hash table to `[PSNode]` instance: Get-Node @{ 'My' = 1, 2, 3; 'Object' = 'Graph' } PathName Name Depth Value -------- ---- ----- ----- 0 {My, Object} .EXAMPLE # select a sub node in an object graph The following example parses a hash table to `[PSNode]` instance and selects the second (`0` indexed) item in the `My` map node '.My[1]' | Get-Node @{ 'My' = 1, 2, 3; 'Object' = 'Graph' } PathName Name Depth Value -------- ---- ----- ----- .My[1] 1 2 2 .PARAMETER InputObject The concerned object graph or node. .PARAMETER Path Specifies the path to a specific node in the object graph. The path might be either: * As [String] a "dot-property" selection as defined by the `PathName` property a specific node. * A array of strings (dictionary keys or Property names) and/or Integers (list indices). * A object (`PSNode[]`) list where each `Name` property defines the path .PARAMETER MaxDepth Specifies the maximum depth that an object graph might be recursively iterated before it throws an error. The failsafe will prevent infinitive loops for circular references as e.g. in: $Test = @{Guid = New-Guid} $Test.Parent = $Test The default `MaxDepth` is defined by `[PSNode]::DefaultMaxDepth = 10`. > [!Note] > The `MaxDepth` is bound to the root node of the object graph. Meaning that a descendent node > at depth of 3 can only recursively iterated (`10 - 3 =`) `7` times. #> function Get-Node { [OutputType([PSNode])] [CmdletBinding()] param( [Parameter(Mandatory = $true)] $InputObject, [Parameter(ValueFromPipeLine = $true, ValueFromPipelineByPropertyName = $true)] $Path, [Int] $MaxDepth ) begin { function StopError($Exception, $Id = 'IncorrectArgument', $Group = [Management.Automation.ErrorCategory]::SyntaxError, $Object){ if ($Exception -is [System.Management.Automation.ErrorRecord]) { $Exception = $Exception.Exception } elseif ($Exception -isnot [Exception]) { $Exception = [ArgumentException]$Exception } $PSCmdlet.ThrowTerminatingError([System.Management.Automation.ErrorRecord]::new($Exception, $Id, $Group, $Object)) } } process { $Node = [PSNode]::ParseInput($InputObject, $MaxDepth) if ($Null -eq $Path) { $Node } else { $Node.GetDescendentNode($Path) } } } |