functions/Get-DbaAgentOperator.ps1

function Get-DbaAgentOperator {
    <#
    .SYNOPSIS
        Returns all SQL Agent operators on a SQL Server Agent.
 
    .DESCRIPTION
        This function returns SQL Agent operators.
 
    .PARAMETER SqlInstance
        The target SQL Server instance or instances. This can be a collection and receive pipeline input to allow the function to be executed against multiple SQL Server instances.
 
    .PARAMETER SqlCredential
        Login to the target instance using alternative credentials. Windows and SQL Authentication supported. Accepts credential objects (Get-Credential)
 
    .PARAMETER Operator
        The operator(s) to process - this list is auto-populated from the server. If unspecified, all operators will be processed.
 
    .PARAMETER ExcludeOperator
        The operator(s) to exclude - this list is auto-populated from the server
 
    .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: Agent, Operator
        Author: Klaas Vandenberghe (@PowerDBAKlaas)
 
        Website: https://dbatools.io
        Copyright: (c) 2018 by dbatools, licensed under MIT
        License: MIT https://opensource.org/licenses/MIT
 
    .LINK
        https://dbatools.io/Get-DbaAgentOperator
 
    .EXAMPLE
        PS C:\> Get-DbaAgentOperator -SqlInstance ServerA,ServerB\instanceB
 
        Returns any SQL Agent operators on serverA and serverB\instanceB
 
    .EXAMPLE
        PS C:\> 'ServerA','ServerB\instanceB' | Get-DbaAgentOperator
 
        Returns all SQL Agent operators on serverA and serverB\instanceB
 
    .EXAMPLE
        PS C:\> Get-DbaAgentOperator -SqlInstance ServerA -Operator Dba1,Dba2
 
        Returns only the SQL Agent Operators Dba1 and Dba2 on ServerA.
 
    .EXAMPLE
        PS C:\> Get-DbaAgentOperator -SqlInstance ServerA,ServerB -ExcludeOperator Dba3
 
        Returns all the SQL Agent operators on ServerA and ServerB, except the Dba3 operator.
 
#>

    [CmdletBinding()]
    param (
        [parameter(Position = 0, Mandatory, ValueFromPipeline)]
        [Alias("ServerInstance", "SqlServer")]
        [DbaInstanceParameter[]]$SqlInstance,
        [PSCredential]
        $SqlCredential,
        [object[]]$Operator,
        [object[]]$ExcludeOperator,
        [Alias('Silent')]
        [switch]$EnableException
    )
    process {
        foreach ($instance in $SqlInstance) {
            try {
                $server = Connect-SqlInstance -SqlInstance $instance -SqlCredential $SqlCredential
            } catch {
                Stop-Function -Message "Failure" -Category ConnectionError -ErrorRecord $_ -Target $instance -Continue
            }

            Write-Message -Level Verbose -Message "Getting Edition from $server"
            Write-Message -Level Verbose -Message "$server is a $($server.Edition)"

            if ($server.Edition -like 'Express*') {
                Stop-Function -Message "There is no SQL Agent on $server, it's a $($server.Edition)" -Continue -Target $server
            }

            $defaults = "ComputerName", "SqlInstance", "InstanceName", "Name", "ID", "Enabled as IsEnabled", "EmailAddress", "LastEmail"

            if ($Operator) {
                $operators = $server.JobServer.Operators | Where-Object Name -In $Operator
            } elseif ($ExcludeOperator) {
                $operators = $server.JobServer.Operators | Where-Object Name -NotIn $ExcludeOperator
            } else {
                $operators = $server.JobServer.Operators
            }

            $alerts = $server.JobServer.alerts

            foreach ($operat in $operators) {

                $jobs = $server.JobServer.jobs | Where-Object { $_.OperatorToEmail, $_.OperatorToNetSend, $_.OperatorToPage -contains $operat.Name }
                $lastemail = [dbadatetime]$operat.LastEmailDate

                $operatAlerts = @()
                foreach ($alert in $alerts) {
                    $dtAlert = $alert.EnumNotifications($operat.Name)
                    if ($dtAlert.Rows.Count -gt 0) {
                        $operatAlerts += $alert.Name
                        $alertlastemail = [dbadatetime]$alert.LastOccurrenceDate
                    }
                }

                Add-Member -Force -InputObject $operat -MemberType NoteProperty -Name ComputerName -Value $server.ComputerName
                Add-Member -Force -InputObject $operat -MemberType NoteProperty -Name InstanceName -Value $server.ServiceName
                Add-Member -Force -InputObject $operat -MemberType NoteProperty -Name SqlInstance -Value $server.DomainInstanceName
                Add-Member -Force -InputObject $operat -MemberType NoteProperty -Name RelatedJobs -Value $jobs
                Add-Member -Force -InputObject $operat -MemberType NoteProperty -Name LastEmail -Value $lastemail
                Add-Member -Force -InputObject $operat -MemberType NoteProperty -Name RelatedAlerts -Value $operatAlerts
                Add-Member -Force -InputObject $operat -MemberType NoteProperty -Name AlertLastEmail -Value $alertlastemail
                Select-DefaultView -InputObject $operat -Property $defaults
            }
        }
    }
}