PSGraylog/Functions/Public/Get-GraylogStreamId.ps1

function Get-GraylogStreamId {
	<#
	.SYNOPSIS
		Gets the ID of a log stream in Graylog.
	.DESCRIPTION
		Gets the ID of a log stream in Graylog using the provided log name.
	.PARAMETER LogName
		The name of the log stream to get the ID for, the log name has to be an exact match for a known log stream.
	.OUTPUTS
		The ID of the log stream if it exists, otherwise null.
	.EXAMPLE
		Get-GraylogStreamId -LogName "Windows Security"
		Gets the ID of the log stream with the name "Windows Security" (645b6fdd9d3689589cdce1bc).
	#>
	param (
		[Parameter(Mandatory)]
		[ValidateSet("Infoblox", "Infoblox DNS", "Windows Application", "Windows Security", "Windows System")]
		[string]
		$LogName
	)

	$Stream = (Get-GraylogStreams).Where{$_.Title -eq $LogName}
	if ($null -eq $Stream) { return $null }
	return $Stream.Id
}