From 3d7b16d61d324d976f0897b0710514ceaef41b7c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan-Otto=20Kr=C3=B6pke?= <mail@jkroepke.de>
Date: Sat, 21 Jun 2025 11:28:30 +0200
Subject: [PATCH] [0.30] fix: added count checks (#2083) (#2089)

---
 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 ad728e81..d31136f7 100644
--- a/internal/collector/ad/ad.go
+++ b/internal/collector/ad/ad.go
@@ -520,6 +520,8 @@ 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 3e17fdcc..fbe3a2a7 100644
--- a/internal/collector/adfs/adfs.go
+++ b/internal/collector/adfs/adfs.go
@@ -385,6 +385,8 @@ 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 6af92de5..b076322b 100644
--- a/internal/collector/cache/cache.go
+++ b/internal/collector/cache/cache.go
@@ -288,6 +288,8 @@ 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 122547f6..0df59999 100644
--- a/internal/collector/dhcp/dhcp.go
+++ b/internal/collector/dhcp/dhcp.go
@@ -403,6 +403,8 @@ 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 957bb9f9..9933e958 100644
--- a/internal/collector/dns/dns.go
+++ b/internal/collector/dns/dns.go
@@ -345,6 +345,8 @@ 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 b574fcc0..5dd4c53b 100644
--- a/internal/collector/system/system.go
+++ b/internal/collector/system/system.go
@@ -157,6 +157,8 @@ 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 80f31a26..f4e0e3ea 100644
--- a/internal/collector/time/time.go
+++ b/internal/collector/time/time.go
@@ -245,7 +245,9 @@ func (c *Collector) collectTime(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(