Add-DbaRegServerGroup.ps1

function Add-DbaRegServerGroup {
    <#
    .SYNOPSIS
        Adds registered server groups to SQL Server Central Management Server (CMS)

    .DESCRIPTION
        Adds registered server groups to SQL Server Central Management Server (CMS). If you need more flexibility, look into Import-DbaRegServer which accepts multiple kinds of input and allows you to add reg servers and groups from different CMS.

    .PARAMETER SqlInstance
        The target SQL Server instance

    .PARAMETER SqlCredential
        Login to the target instance using alternative credentials. Accepts PowerShell credentials (Get-Credential).

        Windows Authentication, SQL Server Authentication, Active Directory - Password, and Active Directory - Integrated are all supported.

        For MFA support, please use Connect-DbaInstance.

    .PARAMETER Name
        The name of the registered server group.

    .PARAMETER Description
        The description for the registered server group

    .PARAMETER Group
        The SQL Server Central Management Server group. If no groups are specified, the new group will be created at the root.
        You can pass sub groups using the '\' to split the path. Group\SubGroup will create both folders. Folder 'SubGroup' under 'Group' folder.

    .PARAMETER InputObject
        Allows results from Get-DbaRegServerGroup to be piped in

    .PARAMETER WhatIf
        Shows what would happen if the command were to run. No actions are actually performed.

    .PARAMETER Confirm
        Prompts you for confirmation before executing any changing operations within the command.

    .PARAMETER EnableException
        By default, when something goes wrong we try to catch it, interpret it and give you a friendly warning message.

        This avoids overwhelming you with "sea of red" exceptions, but is inconvenient because it basically disables advanced scripting.

        Using this switch turns this "nice by default" feature off and enables you to catch exceptions with your own try/catch.

    .NOTES
        Tags: RegisteredServer, CMS
        Author: Chrissy LeMaire (@cl), netnerds.net

        Website: https://dbatools.io
        Copyright: (c) 2018 by dbatools, licensed under MIT
        License: MIT https://opensource.org/licenses/MIT

    .LINK
        https://dbatools.io/Add-DbaRegServerGroup

    .EXAMPLE
        PS C:\> Add-DbaRegServerGroup -SqlInstance sql2012 -Name HR

        Creates a registered server group called HR, in the root of sql2012's CMS

    .EXAMPLE
        PS C:\> Add-DbaRegServerGroup -SqlInstance sql2012, sql2014 -Name sub-folder -Group HR

        Creates a registered server group on sql2012 and sql2014 called sub-folder within the HR group

    .EXAMPLE
        PS C:\> Get-DbaRegServerGroup -SqlInstance sql2012, sql2014 -Group HR | Add-DbaRegServerGroup -Name sub-folder

        Creates a registered server group on sql2012 and sql2014 called sub-folder within the HR group of each server

    #>
    [CmdletBinding(SupportsShouldProcess)]
    param (
        [DbaInstanceParameter[]]$SqlInstance,
        [PSCredential]$SqlCredential,
        [parameter(Mandatory)]
        [string]$Name,
        [string]$Description,
        [string]$Group,
        [parameter(ValueFromPipeline)]
        [Microsoft.SqlServer.Management.RegisteredServers.ServerGroup[]]$InputObject,
        [switch]$EnableException
    )
    process {
        foreach ($instance in $SqlInstance) {
            if ((Test-Bound -ParameterName Group)) {
                $InputObject += Get-DbaRegServerGroup -SqlInstance $instance -SqlCredential $SqlCredential -Group $Group
            } else {
                $InputObject += Get-DbaRegServerGroup -SqlInstance $instance -SqlCredential $SqlCredential -Id 1
            }
        }

        if (-not $SqlInstance -and -not $InputObject) {
            if ((Test-Bound -ParameterName Group)) {
                $InputObject += Get-DbaRegServerGroup -Group $Group
            } else {
                $InputObject += Get-DbaRegServerGroup -Id 1
            }
        }

        foreach ($reggroup in $InputObject) {
            if ($reggroup.Source -eq "Azure Data Studio") {
                Stop-Function -Message "You cannot use dbatools to remove or add registered server groups in Azure Data Studio" -Continue
            }

            $currentInstance = $reggroup.ParentServer

            if ($reggroup.ID) {
                $target = $reggroup.Parent
            } else {
                $target = "Local Registered Server Groups"
            }

            if ($Pscmdlet.ShouldProcess($target, "Adding $Name")) {
                try {
                    $groupList = $Name -split '\\'
                    foreach ($group in $groupList) {
                        if ($null -eq $reggroup.ServerGroups[$group]) {
                            $newGroup = New-Object Microsoft.SqlServer.Management.RegisteredServers.ServerGroup($reggroup, $group)
                            $newGroup.create()
                            $reggroup.refresh()
                        } else {
                            Write-Message -Level Verbose -Message "Group $group already exists. Will continue."
                            $newGroup = $reggroup.ServerGroups[$group]
                        }
                        $reggroup = $reggroup.ServerGroups[$group]
                    }
                    $newgroup.Description = $Description
                    $newgroup.Alter()

                    Get-DbaRegServerGroup -SqlInstance $currentInstance -Group (Get-RegServerGroupReverseParse -object $newgroup)
                    if ($currentInstance.ConnectionContext) {
                        $currentInstance.ConnectionContext.Disconnect()
                    }
                } catch {
                    Stop-Function -Message "Failed to add $reggroup" -ErrorRecord $_ -Continue
                }
            }
        }
    }
}