Draft of the configuration and resource DSL

PSDscExecutor/Functions/DscExecConfiguration.ps1

@@ -0,0 +1,39 @@
+<#
+    .SYNOPSIS
+        .
+
+    .DESCRIPTION
+        .
+
+    .INPUTS
+        .
+
+    .OUTPUTS
+        .
+
+    .EXAMPLE
+        PS C:\> DscExecConfiguration
+        .
+
+    .LINK
+        https://github.com/claudiospizzi/PSDscExecutor
+#>
+function DscExecConfiguration
+{
+    [CmdletBinding()]
+    param
+    (
+        [Parameter(Mandatory = $true, Position = 0)]
+        [System.Management.Automation.ScriptBlock]
+        $Definition
+    )
+
+    try
+    {
+        & $Definition | Out-Null
+    }
+    catch
+    {
+        $PSCmdlet.ThrowTerminatingError($_)
+    }
+}

PSDscExecutor/Functions/DscExecResource.ps1

@@ -0,0 +1,148 @@
+<#
+    .SYNOPSIS
+        .
+
+    .DESCRIPTION
+        .
+
+    .INPUTS
+        .
+
+    .OUTPUTS
+        .
+
+    .EXAMPLE
+        PS C:\> DscExecResource
+        .
+
+    .LINK
+        https://github.com/claudiospizzi/PSDscExecutor
+#>
+function DscExecResource
+{
+    [CmdletBinding()]
+    param
+    (
+        [Parameter(Mandatory = $true, Position = 0)]
+        [System.String]
+        $ModuleName,
+
+        [Parameter(Mandatory = $true, Position = 1)]
+        [System.String]
+        $ResourceName,
+
+        [Parameter(Mandatory = $true, Position = 2)]
+        [System.String]
+        $Name,
+
+        [Parameter(Mandatory = $true, Position = 3)]
+        [System.Collections.Hashtable]
+        $Property
+    )
+
+    try
+    {
+        if ($ModuleName.Contains('@'))
+        {
+            # The module definition contains the required version. Extract the
+            # version of the definition and the get the DSC resource.
+            $ModuleName, $moduleVersion = $ModuleName.Split('@', 2)
+            $dscResource = Get-DscResource -Module @{ ModuleName = $ModuleName; RequiredVersion = $moduleVersion } -Name $ResourceName
+        }
+        else
+        {
+            # Get the DSC resource right away. Check if the DSC resource was
+            # loaded and extract the version.
+            $dscResource = Get-DscResource -Module $ModuleName -Name $ResourceName
+            $moduleVersion = $dscResource.Version
+            if ($null -eq $moduleVersion)
+            {
+                $moduleVersion = 'n/a'
+                if ($dscResource.Path -like 'C:\Windows\System32\WindowsPowershell\v1.0\Modules\PSDesiredStateConfiguration\DscResources\*')
+                {
+                    $moduleVersion = '1.1'
+                }
+            }
+        }
+
+        # Verify all mandatory properties are part of the provided properties
+        # and extract them in a dedicated hash table.
+        $keyProperties = @{}
+        foreach ($propertyKey in $dscResource.Properties.Where({ $_.IsMandatory }).Name)
+        {
+            if ($Property.Keys -notcontains $propertyKey)
+            {
+                throw "The mandatory property $propertyKey is not specified in $ModuleName@$moduleVersion/$ResourceName/$Name."
+            }
+            $keyProperties[$propertyKey] = $Property[$propertyKey]
+        }
+
+        # Copy and verify all provided properties.
+        $allProperties = @{}
+        foreach ($propertyKey in $Property.Keys)
+        {
+            if ($dscResource.Properties.Name -notcontains $propertyKey)
+            {
+                throw "The property $propertyKey not found in the resource $ModuleName@$moduleVersion/$ResourceName."
+            }
+            $allProperties[$propertyKey] = $Property[$propertyKey]
+        }
+
+        # Prepare all the DSC invocation helpers
+        $invokeDscResourceVerbose = "[$ModuleName@$moduleVersion] [$ResourceName] [$Name]"
+        # $verboseResourceName  = "[$ModuleName@$moduleVersion] [$ResourceName] [$Name]"
+        # $verboseResourceSpace = "[$ModuleName@$moduleVersion] [$ResourceName]" -replace '.', ' '
+        # $verboseInstanceName  = "$verboseResourceName [$Name]"
+        # $verboseInstanceSpace = $verboseInstanceName -replace '.', ' '
+        $invokeDscResourceSplat = @{
+            Name       = $ResourceName
+            ModuleName = @{
+                ModuleName      = $ModuleName
+                RequiredVersion = $moduleVersion
+            }
+        }
+
+        Write-Verbose $invokeDscResourceVerbose
+
+        # Loop over the resource as long as it is not in the desired state.
+        $inDesiredState = $false
+        while (-not $inDesiredState)
+        {
+            Write-Verbose "$invokeDscResourceVerbose [Test] Start"
+
+            $inDesiredState = Invoke-DscResource @invokeDscResourceSplat -Method 'Test' -Property $allProperties | Select-Object -ExpandProperty 'InDesiredState'
+
+            Write-Verbose "$invokeDscResourceVerbose [Test]   DesiredState = $inDesiredState"
+
+            Write-Verbose "$invokeDscResourceVerbose [Test] End"
+
+            if (-not $inDesiredState)
+            {
+                Write-Verbose "$invokeDscResourceVerbose [Set] Start"
+
+                Invoke-DscResource @invokeDscResourceSplat -Method 'Set' -Property $allProperties
+
+                Write-Verbose "$invokeDscResourceVerbose [Set] End"
+            }
+        }
+
+        Write-Verbose "$invokeDscResourceVerbose [Get] Start"
+
+        $stateData = Invoke-DscResource @invokeDscResourceSplat -Method 'Get' -Property $keyProperties
+
+        foreach ($stateDataPropertyKey in $stateData.Keys)
+        {
+            Write-Verbose "$invokeDscResourceVerbose [Get]   $stateDataPropertyKey = $($stateData[$stateDataPropertyKey])"
+        }
+
+        Write-Verbose "$invokeDscResourceVerbose [Get] End"
+
+        Write-Verbose $invokeDscResourceVerbose
+
+        return $stateData
+    }
+    catch
+    {
+        $PSCmdlet.ThrowTerminatingError($_)
+    }
+}

PSDscExecutor/Helpers/Register-DscResourceFunction.ps1

@@ -0,0 +1,51 @@
+<#
+    .SYNOPSIS
+        .
+
+    .DESCRIPTION
+        .
+
+    .INPUTS
+        .
+
+    .OUTPUTS
+        .
+
+    .EXAMPLE
+        PS C:\> Register-DscResourceFunction
+        .
+
+    .LINK
+        https://github.com/claudiospizzi/PSDscExecutor
+#>
+function Register-DscResourceFunction
+{
+    [CmdletBinding()]
+    param
+    (
+        [Parameter(Mandatory = $true, ValueFromPipeline = $true)]
+        [Microsoft.PowerShell.DesiredStateConfiguration.DscResourceInfo]
+        $DscResourceInfo,
+
+        [Parameter(Mandatory = $false)]
+        [ValidateSet('Script', 'Global')]
+        [System.String]
+        $Scope = 'Script'
+    )
+
+    begin
+    {
+        try
+        {
+            # Resource with no module name?!?
+            $functionName = '{0}:{1}@{2}\{3}' -f $Scope, $DscResourceInfo.ModuleName, $DscResourceInfo.Version, $DscResourceInfo.Name
+            $functionCode = [System.Management.Automation.ScriptBlock]::Create('param ($A) Write-Host "A: $A"')
+
+            New-Item -Path 'Function:\' -Name $functionName -Value $functionCode | Out-Null
+        }
+        catch
+        {
+            $PSCmdlet.ThrowTerminatingError($_)
+        }
+    }
+}

PSDscExecutor/PSDscExecutor.psd1

@@ -64,7 +64,10 @@
     NestedModules = @()
 
     # Functions to export from this module, for best performance, do not use wildcards and do not delete the entry, use an empty array if there are no functions to export.
-    FunctionsToExport = @()
+    FunctionsToExport = @(
+        'DscExecConfiguration'
+        'DscExecResource'
+    )
 
     # Cmdlets to export from this module, for best performance, do not use wildcards and do not delete the entry, use an empty array if there are no cmdlets to export.
     CmdletsToExport = @()

PSDscExecutor/PSDscExecutor.psm1

@@ -33,3 +33,6 @@ $Script:PSModuleVersion = (Import-PowerShellDataFile -Path "$Script:PSModulePath
 # Define module behaviour
 $ErrorActionPreference = 'Stop'
 Set-StrictMode -Version 'Latest'
+
+# Now, register all available DSC resource functions
+# Get-DscResource | Register-DscResourceFunction -Scope 'Script'