From d1a807840c517473b38f8657bbc748d303cfceb7 Mon Sep 17 00:00:00 2001
From: Stefan Lengauer <stefan.lengauer@fabasoft.com>
Date: Wed, 4 Mar 2020 14:49:59 +0100
Subject: [PATCH] Fix cs collector crashing when running on a domain joined
 machine

The wmi lib does some type checking for nil values.
Use a pointer as a workaround for that.
---
 collector/cs.go | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/collector/cs.go b/collector/cs.go
index 352ac3653..f545b7012 100644
--- a/collector/cs.go
+++ b/collector/cs.go
@@ -67,7 +67,7 @@ type Win32_ComputerSystem struct {
 	TotalPhysicalMemory       uint64
 	DNSHostname               string
 	Domain                    string
-	Workgroup                 string
+	Workgroup                 *string
 }
 
 func (c *CSCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc, error) {
@@ -93,7 +93,7 @@ func (c *CSCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc, er
 	)
 
 	var fqdn string
-	if dst[0].Domain != dst[0].Workgroup {
+	if dst[0].Workgroup == nil || dst[0].Domain != *dst[0].Workgroup {
 		fqdn = dst[0].DNSHostname + "." + dst[0].Domain
 	} else {
 		fqdn = dst[0].DNSHostname