Transpilers/ProxyCommand.psx.ps1
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<# .SYNOPSIS Creates Proxy Commands .DESCRIPTION Generates a Proxy Command for an underlying PowerShell or PipeScript command. .EXAMPLE .\ProxyCommand.psx.ps1 -CommandName Get-Process .EXAMPLE { function [ProxyCommand<'Get-Process'>]GetProcessProxy {} } | .>PipeScript .EXAMPLE .>ProxyCommand -CommandName Get-Process -RemoveParameter * .EXAMPLE Invoke-PipeScript -ScriptBlock {[ProxyCommand('Get-Process')]param()} .EXAMPLE Invoke-PipeScript -ScriptBlock { [ProxyCommand('Get-Process', RemoveParameter='*', DefaultParameter={ @{id='$pid'} })] param() } .EXAMPLE { function Get-MyProcess { [ProxyCommand('Get-Process', RemoveParameter='*', DefaultParameter={ @{id='$pid'} })] param() } } | .>PipeScript #> param( # The ScriptBlock that will become a proxy command. This should be empty, since it is ignored. [Parameter(ValueFromPipeline)] [scriptblock] $ScriptBlock, # The name of the command being proxied. [Parameter(Mandatory,Position=0)] [string] $CommandName, # If provided, will remove any number of parameters from the proxy command. [string[]] $RemoveParameter, # Any default parameters for the ProxyCommand. [Collections.IDictionary] $DefaultParameter ) $resolvedCommand = $ExecutionContext.SessionState.InvokeCommand.GetCommand($CommandName, 'Alias,Function,Cmdlet') if (-not $resolvedCommand) { Write-Error "Could not resolve -CommandName '$CommandName'" return } $commandMetadata = [Management.Automation.CommandMetadata]$resolvedCommand if ($RemoveParameter) { $toRemove = @( foreach ($paramName in $commandMetadata.Parameters.Keys) { if ($RemoveParameter -contains $paramName) { $paramName } else { foreach ($rp in $RemoveParameter) { if ($paramName -like $rp) { $paramName break } } } } ) $null = foreach ($tr in $toRemove) { $commandMetadata.Parameters.Remove($tr) } } $proxyCommandText = [Management.Automation.ProxyCommand]::Create($commandMetadata) if ($DefaultParameter) { $toSplat = "@' $(ConvertTo-Json $DefaultParameter -Depth 100) '@" $insertPoint = $proxyCommandText.IndexOf('$scriptCmd = {& $wrappedCmd @PSBoundParameters }') $proxyCommandText = $proxyCommandText.Insert($insertPoint,@" `$_DefaultParameters = ConvertFrom-Json $toSplat foreach (`$property in `$_DefaultParameters.psobject.properties) { `$psBoundParameters[`$property.Name] = `$property.Value if (`$property.Value -is [string] -and `$property.Value.StartsWith('`$')) { `$psBoundParameters[`$property.Name] = `$executionContext.SessionState.PSVariable.Get(`$property.Value.Substring(1)).Value } } "@) } [ScriptBlock]::Create($proxyCommandText) |