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Welcome to the Datum.InvokeCommand wiki

^{Datum.InvokeCommand v0.4.1}

Here you will find all the information you need to make use of the Datum.InvokeCommand module, including details of the functions that are available, current capabilities and known issues, and information to help plan a Datum-based DSC implementation using dynamic command execution.

Please leave comments, feature requests, and bug reports in the issues section for this module.

Overview

Datum.InvokeCommand is a handler module for the Datum configuration management framework. It enables dynamic PowerShell command execution and string expansion directly within YAML configuration data files used for PowerShell Desired State Configuration (DSC).

Exported Functions

• Invoke-InvokeCommandAction: The primary action handler invoked by the Datum framework. It evaluates embedded commands (script blocks and expandable strings) within Datum configuration values.
• Test-InvokeCommandFilter: The filter function called by Datum's ConvertTo-Datum on every value during data resolution. Returns $true when a value contains an embedded command that should be processed by the handler.

Getting Started

To get started, download Datum.InvokeCommand from the PowerShell Gallery and then unzip it to one of your PowerShell modules folders (such as $env:ProgramFiles\WindowsPowerShell\Modules).

To install from the PowerShell Gallery using PowerShellGet (in PowerShell 5.0), run the following command:

Find-Module -Name Datum.InvokeCommand -Repository PSGallery | Install-Module

Or with PowerShellGet v3+:

Install-PSResource -Name Datum.InvokeCommand

To confirm installation, run the below command and ensure you see the Datum.InvokeCommand functions available:

Get-Command -Module Datum.InvokeCommand

Requirements

• PowerShell 4.0 or later (Windows PowerShell or PowerShell 7+)
• Datum module (0.40.0 or later recommended)

Quick Start

1. Register the handler in your Datum.yml configuration file:

   DatumHandlers:
     Datum.InvokeCommand::InvokeCommand:
       SkipDuringLoad: true

2. Use embedded commands in your YAML configuration files:

   # Script block
   NodeName: '[x={ $Node.Name }=]'
   
   # Expandable string
   Description: '[x= "$($Node.Role) in $($Node.Environment)" =]'

3. Resolve the configuration:

   Import-Module -Name datum
   Import-Module -Name Datum.InvokeCommand
   
   $datum = New-DatumStructure -DefinitionFile .\DscConfigData\Datum.yml
   $rsop = Get-DatumRsop -Datum $datum -AllNodes $allNodes

For a detailed walkthrough, see the Getting Started guide.

Documentation

• Getting Started ? Step-by-step tutorial for new users.
• Architecture ? Internal processing pipeline, module components, and error handling strategy.
• Troubleshooting ? Common issues, diagnostic steps, and resolution guidance.

Change Log

A full list of changes in each version can be found in the change log.