time: expose clock source sync (#2058)

internal/collector/time/time.go

@@ -33,13 +33,15 @@ import (
 	"github.com/prometheus-community/windows_exporter/internal/types"
 	"github.com/prometheus/client_golang/prometheus"
 	"golang.org/x/sys/windows"
+	"golang.org/x/sys/windows/registry"
 )
 
 const (
 	Name = "time"
 
-	collectorSystemTime = "system_time"
-	collectorNTP        = "ntp"
+	collectorSystemTime  = "system_time"
+	collectorClockSource = "clock_source"
+	collectorNTP         = "ntp"
 )
 
 type Config struct {
@@ -50,6 +52,7 @@ type Config struct {
 var ConfigDefaults = Config{
 	CollectorsEnabled: []string{
 		collectorSystemTime,
+		collectorClockSource,
 		collectorNTP,
 	},
 }
@@ -61,10 +64,13 @@ type Collector struct {
 	perfDataCollector *pdh.Collector
 	perfDataObject    []perfDataCounterValues
 
+	logger *slog.Logger
+
 	ppbCounterPresent bool
 
 	currentTime                     *prometheus.Desc
 	timezone                        *prometheus.Desc
+	clockSource                     *prometheus.Desc
 	clockFrequencyAdjustment        *prometheus.Desc
 	clockFrequencyAdjustmentPPB     *prometheus.Desc
 	computedTimeOffset              *prometheus.Desc
@@ -124,9 +130,11 @@ func (c *Collector) Close() error {
 	return nil
 }
 
-func (c *Collector) Build(_ *slog.Logger, _ *mi.Session) error {
+func (c *Collector) Build(logger *slog.Logger, _ *mi.Session) error {
+	c.logger = logger.With(slog.String("collector", Name))
+
 	for _, collector := range c.config.CollectorsEnabled {
-		if !slices.Contains([]string{collectorSystemTime, collectorNTP}, collector) {
+		if !slices.Contains([]string{collectorSystemTime, collectorClockSource, collectorNTP}, collector) {
 			return fmt.Errorf("unknown collector: %s", collector)
 		}
 	}
@@ -136,16 +144,22 @@ func (c *Collector) Build(_ *slog.Logger, _ *mi.Session) error {
 
 	c.currentTime = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "current_timestamp_seconds"),
-		"OperatingSystem.LocalDateTime",
+		"Current time as reported by the operating system, in unix time.",
 		nil,
 		nil,
 	)
 	c.timezone = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "timezone"),
-		"OperatingSystem.LocalDateTime",
+		"Current timezone as reported by the operating system.",
 		[]string{"timezone"},
 		nil,
 	)
+	c.clockSource = prometheus.NewDesc(
+		prometheus.BuildFQName(types.Namespace, Name, "clock_sync_source"),
+		"This value reflects the sync source of the system clock.",
+		[]string{"type"},
+		nil,
+	)
 	c.clockFrequencyAdjustment = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "clock_frequency_adjustment"),
 		"This value reflects the adjustment made to the local system clock frequency by W32Time in nominal clock units. This counter helps visualize the finer adjustments being made by W32time to synchronize the local clock.",
@@ -189,11 +203,13 @@ func (c *Collector) Build(_ *slog.Logger, _ *mi.Session) error {
 		nil,
 	)
 
-	var err error
+	if slices.Contains(c.config.CollectorsEnabled, collectorNTP) {
+		var err error
 
-	c.perfDataCollector, err = pdh.NewCollector[perfDataCounterValues](pdh.CounterTypeRaw, "Windows Time Service", nil)
-	if err != nil {
-		return fmt.Errorf("failed to create Windows Time Service collector: %w", err)
+		c.perfDataCollector, err = pdh.NewCollector[perfDataCounterValues](pdh.CounterTypeRaw, "Windows Time Service", nil)
+		if err != nil {
+			return fmt.Errorf("failed to create Windows Time Service collector: %w", err)
+		}
 	}
 
 	return nil
@@ -206,7 +222,13 @@ func (c *Collector) Collect(ch chan<- prometheus.Metric) error {
 
 	if slices.Contains(c.config.CollectorsEnabled, collectorSystemTime) {
 		if err := c.collectTime(ch); err != nil {
-			errs = append(errs, fmt.Errorf("failed collecting time metrics: %w", err))
+			errs = append(errs, fmt.Errorf("failed collecting operating system time metrics: %w", err))
+		}
+	}
+
+	if slices.Contains(c.config.CollectorsEnabled, collectorClockSource) {
+		if err := c.collectClockSource(ch); err != nil {
+			errs = append(errs, fmt.Errorf("failed collecting clock source metrics: %w", err))
 		}
 	}
 
@@ -244,6 +266,42 @@ func (c *Collector) collectTime(ch chan<- prometheus.Metric) error {
 	return nil
 }
 
+func (c *Collector) collectClockSource(ch chan<- prometheus.Metric) error {
+	keyPath := `SYSTEM\CurrentControlSet\Services\W32Time\Parameters`
+
+	key, err := registry.OpenKey(registry.LOCAL_MACHINE, keyPath, registry.READ)
+	if err != nil {
+		return fmt.Errorf("failed to open registry key: %w", err)
+	}
+
+	val, _, err := key.GetStringValue("Type")
+	if err != nil {
+		return fmt.Errorf("failed to read 'Type' value: %w", err)
+	}
+
+	for _, validType := range []string{"NTP", "NT5DS", "AllSync", "NoSync", "Local CMOS Clock"} {
+		metricValue := 0.0
+		if val == validType {
+			metricValue = 1.0
+		}
+
+		ch <- prometheus.MustNewConstMetric(
+			c.clockSource,
+			prometheus.GaugeValue,
+			metricValue,
+			validType,
+		)
+	}
+
+	if err := key.Close(); err != nil {
+		c.logger.Debug("failed to close registry key",
+			slog.Any("err", err),
+		)
+	}
+
+	return nil
+}
+
 func (c *Collector) collectNTP(ch chan<- prometheus.Metric) error {
 	err := c.perfDataCollector.Collect(&c.perfDataObject)
 	if err != nil {