From 4891e23d29ca95655f0d01d5267dcca45ffbcb0c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan-Otto=20Kr=C3=B6pke?= <mail@jkroepke.de>
Date: Thu, 19 Jun 2025 16:59:19 +0200
Subject: [PATCH] fix: added count checks (#2083)

---
 internal/collector/ad/ad.go         | 2 ++
 internal/collector/adfs/adfs.go     | 2 ++
 internal/collector/cache/cache.go   | 2 ++
 internal/collector/dhcp/dhcp.go     | 2 ++
 internal/collector/dns/dns.go       | 2 ++
 internal/collector/system/system.go | 2 ++
 internal/collector/time/time.go     | 4 +++-
 7 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/internal/collector/ad/ad.go b/internal/collector/ad/ad.go
index 538f1da6..0ad49cbf 100644
--- a/internal/collector/ad/ad.go
+++ b/internal/collector/ad/ad.go
@@ -522,6 +522,8 @@ func (c *Collector) Collect(ch chan<- prometheus.Metric) error {
 	err := c.perfDataCollector.Collect(&c.perfDataObject)
 	if err != nil {
 		return fmt.Errorf("failed to collect DirectoryServices (AD) metrics: %w", err)
+	} else if len(c.perfDataObject) == 0 {
+		return fmt.Errorf("failed to collect DirectoryServices (AD) metrics: %w", types.ErrNoDataUnexpected)
 	}
 
 	ch <- prometheus.MustNewConstMetric(
diff --git a/internal/collector/adfs/adfs.go b/internal/collector/adfs/adfs.go
index fa54cb2d..38a092a1 100644
--- a/internal/collector/adfs/adfs.go
+++ b/internal/collector/adfs/adfs.go
@@ -387,6 +387,8 @@ func (c *Collector) Collect(ch chan<- prometheus.Metric) error {
 	err := c.perfDataCollector.Collect(&c.perfDataObject)
 	if err != nil {
 		return fmt.Errorf("failed to collect ADFS metrics: %w", err)
+	} else if len(c.perfDataObject) == 0 {
+		return fmt.Errorf("failed to collect ADFS metrics: %w", types.ErrNoDataUnexpected)
 	}
 
 	ch <- prometheus.MustNewConstMetric(
diff --git a/internal/collector/cache/cache.go b/internal/collector/cache/cache.go
index 1139e229..86072c0b 100644
--- a/internal/collector/cache/cache.go
+++ b/internal/collector/cache/cache.go
@@ -290,6 +290,8 @@ func (c *Collector) Collect(ch chan<- prometheus.Metric) error {
 	err := c.perfDataCollector.Collect(&c.perfDataObject)
 	if err != nil {
 		return fmt.Errorf("failed to collect Cache metrics: %w", err)
+	} else if len(c.perfDataObject) == 0 {
+		return fmt.Errorf("failed to collect Cache metrics: %w", types.ErrNoDataUnexpected)
 	}
 
 	ch <- prometheus.MustNewConstMetric(
diff --git a/internal/collector/dhcp/dhcp.go b/internal/collector/dhcp/dhcp.go
index 233a9413..18250a4c 100644
--- a/internal/collector/dhcp/dhcp.go
+++ b/internal/collector/dhcp/dhcp.go
@@ -405,6 +405,8 @@ func (c *Collector) collectServerMetrics(ch chan<- prometheus.Metric) error {
 	err := c.perfDataCollector.Collect(&c.perfDataObject)
 	if err != nil {
 		return fmt.Errorf("failed to collect DHCP Server metrics: %w", err)
+	} else if len(c.perfDataObject) == 0 {
+		return fmt.Errorf("failed to collect DHCP Server metrics: %w", types.ErrNoDataUnexpected)
 	}
 
 	ch <- prometheus.MustNewConstMetric(
diff --git a/internal/collector/dns/dns.go b/internal/collector/dns/dns.go
index dbfa8228..5cf846cf 100644
--- a/internal/collector/dns/dns.go
+++ b/internal/collector/dns/dns.go
@@ -347,6 +347,8 @@ func (c *Collector) collectMetrics(ch chan<- prometheus.Metric) error {
 	err := c.perfDataCollector.Collect(&c.perfDataObject)
 	if err != nil {
 		return fmt.Errorf("failed to collect DNS metrics: %w", err)
+	} else if len(c.perfDataObject) == 0 {
+		return fmt.Errorf("failed to collect DNS metrics: %w", types.ErrNoDataUnexpected)
 	}
 
 	ch <- prometheus.MustNewConstMetric(
diff --git a/internal/collector/system/system.go b/internal/collector/system/system.go
index 4d657830..043a9a06 100644
--- a/internal/collector/system/system.go
+++ b/internal/collector/system/system.go
@@ -159,6 +159,8 @@ func (c *Collector) Collect(ch chan<- prometheus.Metric) error {
 	err := c.perfDataCollector.Collect(&c.perfDataObject)
 	if err != nil {
 		return fmt.Errorf("failed to collect System metrics: %w", err)
+	} else if len(c.perfDataObject) == 0 {
+		return fmt.Errorf("failed to collect System metrics: %w", types.ErrNoDataUnexpected)
 	}
 
 	ch <- prometheus.MustNewConstMetric(
diff --git a/internal/collector/time/time.go b/internal/collector/time/time.go
index df0ccdfc..e878ba7b 100644
--- a/internal/collector/time/time.go
+++ b/internal/collector/time/time.go
@@ -305,7 +305,9 @@ func (c *Collector) collectClockSource(ch chan<- prometheus.Metric) error {
 func (c *Collector) collectNTP(ch chan<- prometheus.Metric) error {
 	err := c.perfDataCollector.Collect(&c.perfDataObject)
 	if err != nil {
-		return fmt.Errorf("failed to collect time metrics: %w", err)
+		return fmt.Errorf("failed to collect Windows Time Service metrics: %w", err)
+	} else if len(c.perfDataObject) == 0 {
+		return fmt.Errorf("failed to collect Windows Time Service metrics: %w", types.ErrNoDataUnexpected)
 	}
 
 	ch <- prometheus.MustNewConstMetric(