functions/Get-DbaRegisteredServer.ps1

#ValidationTags#Messaging,FlowControl,Pipeline,CodeStyle#
function Get-DbaRegisteredServer {
    <#
        .SYNOPSIS
            Gets list of SQL Server objects stored in SQL Server Central Management Server (CMS).

        .DESCRIPTION
            Returns an array of servers found in the CMS.

        .PARAMETER SqlInstance
            SQL Server name or SMO object representing the SQL Server to connect to.

        .PARAMETER SqlCredential
            Login to the target instance using alternative credentials. Windows and SQL Authentication supported. Accepts credential objects (Get-Credential)

        .PARAMETER Name
            Specifies one or more names to include. Name is the visible name in SSMS CMS interface (labeled Registered Server Name)

        .PARAMETER ServerName
            Specifies one or more server names to include. Server Name is the actual instance name (labeled Server Name)

        .PARAMETER Group
            Specifies one or more groups to include from SQL Server Central Management Server.

        .PARAMETER ExcludeGroup
            Specifies one or more Central Management Server groups to exclude.

        .PARAMETER ExcludeCmsServer
            Deprecated, now follows the Microsoft convention of not including it by default. If you'd like to include the CMS Server, use -IncludeSelf

        .PARAMETER Id
            Get server by Id(s)

        .PARAMETER IncludeSelf
            If this switch is enabled, the CMS server itself will be included in the results, along with all other Registered Servers.

        .PARAMETER ResolveNetworkName
            If this switch is enabled, the NetBIOS name and IP address(es) of each server will be returned.

        .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
            Author: Bryan Hamby (@galador)
            Tags: RegisteredServer, CMS

            Website: https://dbatools.io
            Copyright: (C) Chrissy LeMaire, clemaire@gmail.com
            License: MIT https://opensource.org/licenses/MIT

        .LINK
            https://dbatools.io/Get-DbaRegisteredServer

        .EXAMPLE
            Get-DbaRegisteredServer -SqlInstance sqlserver2014a

            Gets a list of servers from the CMS on sqlserver2014a, using Windows Credentials.

        .EXAMPLE
            Get-DbaRegisteredServer -SqlInstance sqlserver2014a -IncludeSelf

            Gets a list of servers from the CMS on sqlserver2014a and includes sqlserver2014a in the output results.

        .EXAMPLE
            Get-DbaRegisteredServer -SqlInstance sqlserver2014a -SqlCredential $credential | Select-Object -Unique -ExpandProperty ServerName

            Returns only the server names from the CMS on sqlserver2014a, using SQL Authentication to authenticate to the server.

        .EXAMPLE
            Get-DbaRegisteredServer -SqlInstance sqlserver2014a -Group HR, Accounting

            Gets a list of servers in the HR and Accounting groups from the CMS on sqlserver2014a.

        .EXAMPLE
            Get-DbaRegisteredServer -SqlInstance sqlserver2014a -Group HR\Development

            Returns a list of servers in the HR and sub-group Development from the CMS on sqlserver2014a.
    #>

    [CmdletBinding()]
    param (
        [parameter(Mandatory, ValueFromPipeline)]
        [Alias("ServerInstance", "SqlServer")]
        [DbaInstanceParameter[]]$SqlInstance,
        [PSCredential]$SqlCredential,
        [string[]]$Name,
        [string[]]$ServerName,
        [Alias("Groups")]
        [object[]]$Group,
        [object[]]$ExcludeGroup,
        [int[]]$Id,
        [switch]$IncludeSelf,
        [switch]$ExcludeCmsServer,
        [switch]$ResolveNetworkName,
        [Alias('Silent')]
        [switch]$EnableException
    )
    begin {
        if ($ResolveNetworkName) {
            $defaults = 'ComputerName', 'FQDN', 'IPAddress', 'Name', 'ServerName', 'Group', 'Description'
        }
        $defaults = 'Name', 'ServerName', 'Group', 'Description'
    }
    process {
        $servers = @()
        foreach ($instance in $SqlInstance) {
            if ($Group) {
                Write-Message -Level Verbose -Message "Connecting to $instance to search for $group"
                $groupservers = Get-DbaRegisteredServerGroup -SqlInstance $instance -SqlCredential $SqlCredential -Group $Group -ExcludeGroup $ExcludeGroup
                if ($groupservers) {
                    $servers += $groupservers.GetDescendantRegisteredServers()
                }
            }
            else {
                Write-Message -Level Verbose -Message "Connecting to $instance"
                try {
                    $serverstore = Get-DbaRegisteredServerStore -SqlInstance $instance -SqlCredential $SqlCredential -EnableException
                }
                catch {
                    Stop-Function -Message "Cannot access Central Management Server '$instance'." -ErrorRecord $_ -Continue
                }
                $servers += ($serverstore.DatabaseEngineServerGroup.GetDescendantRegisteredServers())
                $serverstore.ServerConnection.Disconnect()
            }
        }
        
        if ($Name) {
            Write-Message -Level Verbose -Message "Filtering by name for $name"
            $servers = $servers | Where-Object Name -in $Name
        }

        if ($ServerName) {
            Write-Message -Level Verbose -Message "Filtering by servername for $servername"
            $servers = $servers | Where-Object ServerName -in $ServerName
        }

        if ($Id) {
            Write-Message -Level Verbose -Message "Filtering by id for $Id (1 = default/root)"
            $servers = $servers | Where-Object Id -in $Id
        }

        if ($ExcludeGroup) {
            $excluded = Get-DbaRegisteredServer $serverstore.ServerConnection.SqlConnectionObject -Group $ExcludeGroup
            Write-Message -Level Verbose -Message "Excluding $ExcludeGroup"
            $servers = $servers | Where-Object { $_.Urn.Value -notin $excluded.Urn.Value }
        }

        foreach ($server in $servers) {
            $groupname = Get-RegServerGroupReverseParse $server
            if ($groupname -eq $server.Name) {
                $groupname = $null
            }
            else {
                $groupname = ($groupname).Split("\")
                $groupname = $groupname[0 .. ($groupname.Count - 2)]
                $groupname = ($groupname -join "\")
            }


            Add-Member -Force -InputObject $server -MemberType NoteProperty -Name ComputerName -value $serverstore.ComputerName
            Add-Member -Force -InputObject $server -MemberType NoteProperty -Name InstanceName -value $serverstore.InstanceName
            Add-Member -Force -InputObject $server -MemberType NoteProperty -Name SqlInstance -value $serverstore.SqlInstance
            Add-Member -Force -InputObject $server -MemberType NoteProperty -Name Group -value $groupname
            Add-Member -Force -InputObject $server -MemberType NoteProperty -Name FQDN -Value $null
            Add-Member -Force -InputObject $server -MemberType NoteProperty -Name IPAddress -Value $null

            if ($ResolveNetworkName) {
                try {
                    $lookup = Resolve-DbaNetworkName $server.ServerName -Turbo
                    $server.ComputerName = $lookup.ComputerName
                    $server.FQDN = $lookup.FQDN
                    $server.IPAddress = $lookup.IPAddress
                }
                catch {
                    try {
                        $lookup = Resolve-DbaNetworkName $server.ServerName
                        $server.ComputerName = $lookup.ComputerName
                        $server.FQDN = $lookup.FQDN
                        $server.IPAddress = $lookup.IPAddress
                    }
                    catch { }
                }
            }
            Add-Member -Force -InputObject $server -MemberType ScriptMethod -Name ToString -Value { $this.ServerName }
            Select-DefaultView -InputObject $server -Property $defaults
        }

        if ($IncludeSelf -and $servers) {
            Write-Message -Level Verbose -Message "Adding CMS instance"
            $self = $servers[0].PsObject.Copy()
            $self | Add-Member -MemberType NoteProperty -Name Name -Value "CMS Instance" -Force
            $self.ServerName = $instance
            $self.Description = $null
            $self.SecureConnectionString = $null
            Select-DefaultView -InputObject $self -Property $defaults
        }
    }
    end {
        Test-DbaDeprecation -DeprecatedOn "1.0.0" -Parameter ExcludeCmsServer
        Test-DbaDeprecation -DeprecatedOn "1.0.0" -Alias Get-DbaRegisteredServerName
        Test-DbaDeprecation -DeprecatedOn "1.0.0" -Alias Get-SqlRegisteredServerName
    }
}