Merge pull request #241 from szook/protect-against-empty-result-set

protect against empty wmi query result sets
protect against emtpy wmi query result sets
2026-03-06 18:46:36 +00:00 · 2018-08-08 09:14:27 +02:00 · 2018-08-07 15:47:39 -04:00 · 2018-08-06 11:41:43 +02:00 · 2018-08-05 21:39:43 -04:00
10 changed files with 1111 additions and 1061 deletions
--- a/collector/ad.go
+++ b/collector/ad.go
@@ -3,6 +3,8 @@
 package collector

 import (
+	"errors"
+
 	"github.com/StackExchange/wmi"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/log"
@@ -616,6 +618,9 @@ func (c *ADCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc, er
 	if err := wmi.Query(q, &dst); err != nil {
 		return nil, err
 	}
+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}

 	ch <- prometheus.MustNewConstMetric(
 		c.AddressBookOperationsTotal,
--- a/collector/cs.go
+++ b/collector/cs.go
@@ -4,6 +4,8 @@
 package collector

 import (
+	"errors"
+
 	"github.com/StackExchange/wmi"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/log"
@@ -60,6 +62,9 @@ func (c *CSCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc, er
 	if err := wmi.Query(q, &dst); err != nil {
 		return nil, err
 	}
+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}

 	ch <- prometheus.MustNewConstMetric(
 		c.LogicalProcessors,
--- a/collector/dns.go
+++ b/collector/dns.go
@@ -4,6 +4,8 @@
 package collector

 import (
+	"errors"
+
 	"github.com/StackExchange/wmi"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/log"
@@ -237,6 +239,9 @@ func (c *DNSCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc, e
 	if err := wmi.Query(q, &dst); err != nil {
 		return nil, err
 	}
+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}

 	ch <- prometheus.MustNewConstMetric(
 		c.ZoneTransferRequestsReceived,
--- a/collector/iis.go
+++ b/collector/iis.go
@@ -7,6 +7,7 @@
 package collector

 import (
+	"errors"
 	"fmt"
 	"regexp"

@@ -1738,7 +1739,10 @@ func (c *IISCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc, e
 		return nil, err
 	}

-	if len(dst_cache) > 0 {
+	if len(dst_cache) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}
+
 	ch <- prometheus.MustNewConstMetric(
 		c.ServiceCache_ActiveFlushedEntries,
 		prometheus.GaugeValue,
@@ -1947,7 +1951,6 @@ func (c *IISCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc, e
 		prometheus.CounterValue,
 		float64(dst_cache[0].OutputCacheTotalFlushes),
 	)
-	}

 	return nil, nil
 }
--- a/collector/mssql.go
+++ b/collector/mssql.go
@@ -1769,7 +1769,10 @@ func (c *MSSQLCollector) collectAccessMethods(ch chan<- prometheus.Metric, sqlIn
 		return nil, err
 	}

-	if len(dst) > 0 {
+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}
+
 	v := dst[0]
 	ch <- prometheus.MustNewConstMetric(
 		c.AccessMethodsAUcleanupbatches,
@@ -2071,7 +2074,6 @@ func (c *MSSQLCollector) collectAccessMethods(ch chan<- prometheus.Metric, sqlIn
 		float64(v.WorktablesFromCacheRatio),
 		sqlInstance,
 	)
-	}
 	return nil, nil
 }

@@ -2201,8 +2203,10 @@ func (c *MSSQLCollector) collectBufferManager(ch chan<- prometheus.Metric, sqlIn
 	if err := wmi.Query(q, &dst); err != nil {
 		return nil, err
 	}
+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}

-	if len(dst) > 0 {
 	v := dst[0]

 	ch <- prometheus.MustNewConstMetric(
@@ -2358,7 +2362,7 @@ func (c *MSSQLCollector) collectBufferManager(ch chan<- prometheus.Metric, sqlIn
 		float64(v.Targetpages),
 		sqlInstance,
 	)
-	}
+
 	return nil, nil
 }

@@ -2998,8 +3002,10 @@ func (c *MSSQLCollector) collectGeneralStatistics(ch chan<- prometheus.Metric, s
 	if err := wmi.Query(q, &dst); err != nil {
 		return nil, err
 	}
+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}

-	if len(dst) > 0 {
 	v := dst[0]
 	ch <- prometheus.MustNewConstMetric(
 		c.GenStatsActiveTempTables,
@@ -3168,7 +3174,7 @@ func (c *MSSQLCollector) collectGeneralStatistics(ch chan<- prometheus.Metric, s
 		float64(v.UserConnections),
 		sqlInstance,
 	)
-	}
+
 	return nil, nil
 }

@@ -3280,8 +3286,10 @@ func (c *MSSQLCollector) collectMemoryManager(ch chan<- prometheus.Metric, sqlIn
 	if err := wmi.Query(q, &dst); err != nil {
 		return nil, err
 	}
+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}

-	if len(dst) > 0 {
 	v := dst[0]

 	ch <- prometheus.MustNewConstMetric(
@@ -3423,7 +3431,7 @@ func (c *MSSQLCollector) collectMemoryManager(ch chan<- prometheus.Metric, sqlIn
 		float64(v.TotalServerMemoryKB*1024),
 		sqlInstance,
 	)
-	}
+
 	return nil, nil
 }

@@ -3451,7 +3459,10 @@ func (c *MSSQLCollector) collectSQLStats(ch chan<- prometheus.Metric, sqlInstanc
 		return nil, err
 	}

-	if len(dst) > 0 {
+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}
+
 	v := dst[0]

 	ch <- prometheus.MustNewConstMetric(
@@ -3530,6 +3541,6 @@ func (c *MSSQLCollector) collectSQLStats(ch chan<- prometheus.Metric, sqlInstanc
 		float64(v.UnsafeAutoParamsPersec),
 		sqlInstance,
 	)
-	}
+
 	return nil, nil
 }
--- a/collector/os.go
+++ b/collector/os.go
@@ -4,6 +4,7 @@
 package collector

 import (
+	"errors"
 	"time"

 	"github.com/StackExchange/wmi"
@@ -142,6 +143,10 @@ func (c *OSCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc, er
 		return nil, err
 	}

+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}
+
 	ch <- prometheus.MustNewConstMetric(
 		c.PhysicalMemoryFreeBytes,
 		prometheus.GaugeValue,
--- a/collector/system.go
+++ b/collector/system.go
@@ -4,6 +4,7 @@
 package collector

 import (
+	"errors"
 	"github.com/StackExchange/wmi"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/log"
@@ -94,6 +95,9 @@ func (c *SystemCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc
 	if err := wmi.Query(q, &dst); err != nil {
 		return nil, err
 	}
+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}

 	ch <- prometheus.MustNewConstMetric(
 		c.ContextSwitchesTotal,
--- a/collector/tcp.go
+++ b/collector/tcp.go
@@ -5,6 +5,7 @@
 package collector

 import (
+	"errors"
 	"github.com/StackExchange/wmi"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/log"
@@ -118,6 +119,9 @@ func (c *TCPCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc, e
 	if err := wmi.Query(q, &dst); err != nil {
 		return nil, err
 	}
+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}

 	// Counters
 	ch <- prometheus.MustNewConstMetric(
--- a/collector/vmware.go
+++ b/collector/vmware.go
@@ -2,6 +2,8 @@
 package collector

 import (
+	"errors"
+
 	"github.com/StackExchange/wmi"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/log"
@@ -201,6 +203,9 @@ func (c *VmwareCollector) collectMem(ch chan<- prometheus.Metric) (*prometheus.D
 	if err := wmi.Query(q, &dst); err != nil {
 		return nil, err
 	}
+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}

 	ch <- prometheus.MustNewConstMetric(
 		c.MemActive,
@@ -287,6 +292,9 @@ func (c *VmwareCollector) collectCpu(ch chan<- prometheus.Metric) (*prometheus.D
 	if err := wmi.Query(q, &dst); err != nil {
 		return nil, err
 	}
+	if len(dst) == 0 {
+		return nil, errors.New("WMI query returned empty result set")
+	}

 	ch <- prometheus.MustNewConstMetric(
 		c.CpuLimitMHz,
--- a/exporter.go
+++ b/exporter.go
@@ -185,7 +185,7 @@ func main() {
 		).Default("/metrics").String()
 		enabledCollectors = kingpin.Flag(
 			"collectors.enabled",
-			"Comma-separated list of collectors to use. Use '[default]' as a placeholder for all the collectors enabled by default.").
+			"Comma-separated list of collectors to use. Use '[defaults]' as a placeholder for all the collectors enabled by default.").
 			Default(filterAvailableCollectors(defaultCollectors)).String()
 		printCollectors = kingpin.Flag(
 			"collectors.print",
Author	SHA1	Message	Date
Calle Pettersson	fe7e5cb4d8	Merge pull request #241 from szook/protect-against-empty-result-set protect against empty wmi query result sets	2018-08-08 09:14:27 +02:00
Steve Zook	c156f2bcbe	protect against emtpy wmi query result sets If an WMI query were to return an empty result set, trying to access the first element in the result set would result in a `panic: runtime error: index out of range` error. add logic to explicitly check if the result set size is 0 and return an error rather. Fixes https://github.com/martinlindhe/wmi_exporter/issues/240	2018-08-07 15:47:39 -04:00
Calle Pettersson	832771b4a2	Merge pull request #238 from bbigras/patch-1 fix typo in exporter.go	2018-08-06 11:41:43 +02:00
Bruno Bigras	16fecfbc67	fix typo in exporter.go	2018-08-05 21:39:43 -04:00