filetime: add collector (#1639)

Signed-off-by: Jan-Otto Kröpke <mail@jkroepke.de>

pkg/collector/collector.go

@@ -23,6 +23,7 @@ import (
 	"github.com/prometheus-community/windows_exporter/pkg/collector/diskdrive"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/dns"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/exchange"
+	"github.com/prometheus-community/windows_exporter/pkg/collector/filetime"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/fsrmquota"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/hyperv"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/iis"
@@ -90,6 +91,7 @@ func NewWithConfig(config Config) *MetricCollectors {
 	collectors[diskdrive.Name] = diskdrive.New(&config.DiskDrive)
 	collectors[dns.Name] = dns.New(&config.DNS)
 	collectors[exchange.Name] = exchange.New(&config.Exchange)
+	collectors[filetime.Name] = filetime.New(&config.Filetime)
 	collectors[fsrmquota.Name] = fsrmquota.New(&config.Fsrmquota)
 	collectors[hyperv.Name] = hyperv.New(&config.Hyperv)
 	collectors[iis.Name] = iis.New(&config.IIS)

pkg/collector/config.go

@@ -14,6 +14,7 @@ import (
 	"github.com/prometheus-community/windows_exporter/pkg/collector/diskdrive"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/dns"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/exchange"
+	"github.com/prometheus-community/windows_exporter/pkg/collector/filetime"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/fsrmquota"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/hyperv"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/iis"
@@ -63,6 +64,7 @@ type Config struct {
 	DiskDrive        diskdrive.Config         `yaml:"diskdrive"` //nolint:tagliatelle
 	DNS              dns.Config               `yaml:"dns"`
 	Exchange         exchange.Config          `yaml:"exchange"`
+	Filetime         filetime.Config          `yaml:"filetime"`
 	Fsrmquota        fsrmquota.Config         `yaml:"fsrmquota"`
 	Hyperv           hyperv.Config            `yaml:"hyperv"`
 	IIS              iis.Config               `yaml:"iis"`
@@ -115,6 +117,7 @@ var ConfigDefaults = Config{
 	DiskDrive:        diskdrive.ConfigDefaults,
 	DNS:              dns.ConfigDefaults,
 	Exchange:         exchange.ConfigDefaults,
+	Filetime:         filetime.ConfigDefaults,
 	Fsrmquota:        fsrmquota.ConfigDefaults,
 	Hyperv:           hyperv.ConfigDefaults,
 	IIS:              iis.ConfigDefaults,

pkg/collector/filetime/filetime.go

@@ -0,0 +1,175 @@
+//go:build windows
+
+package filetime
+
+import (
+	"fmt"
+	"log/slog"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+
+	"github.com/alecthomas/kingpin/v2"
+	"github.com/bmatcuk/doublestar/v4"
+	"github.com/prometheus-community/windows_exporter/pkg/types"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/yusufpapurcu/wmi"
+)
+
+const Name = "filetime"
+
+type Config struct {
+	filePatterns []string
+}
+
+var ConfigDefaults = Config{
+	filePatterns: []string{},
+}
+
+// A Collector is a Prometheus Collector for collecting file times.
+type Collector struct {
+	config Config
+
+	fileMTime *prometheus.Desc
+}
+
+func New(config *Config) *Collector {
+	if config == nil {
+		config = &ConfigDefaults
+	}
+
+	if config.filePatterns == nil {
+		config.filePatterns = ConfigDefaults.filePatterns
+	}
+
+	c := &Collector{
+		config: *config,
+	}
+
+	return c
+}
+
+func NewWithFlags(app *kingpin.Application) *Collector {
+	c := &Collector{
+		config: ConfigDefaults,
+	}
+	c.config.filePatterns = make([]string, 0)
+
+	var filePatterns string
+
+	app.Flag(
+		"collectors.filetime.file-patterns",
+		"Comma-separated list of file patterns. Each pattern is a glob pattern that can contain `*`, `?`, and `**` (recursive). See https://github.com/bmatcuk/doublestar#patterns",
+	).Default(strings.Join(ConfigDefaults.filePatterns, ",")).StringVar(&filePatterns)
+
+	app.Action(func(*kingpin.ParseContext) error {
+		// doublestar.Glob() requires forward slashes
+		c.config.filePatterns = strings.Split(filepath.ToSlash(filePatterns), ",")
+
+		return nil
+	})
+
+	return c
+}
+
+func (c *Collector) GetName() string {
+	return Name
+}
+
+func (c *Collector) GetPerfCounter(_ *slog.Logger) ([]string, error) {
+	return []string{}, nil
+}
+
+func (c *Collector) Close(_ *slog.Logger) error {
+	return nil
+}
+
+func (c *Collector) Build(logger *slog.Logger, _ *wmi.Client) error {
+	logger.Info("filetime collector is in an experimental state! It may subject to change.",
+		slog.String("collector", Name),
+	)
+
+	c.fileMTime = prometheus.NewDesc(
+		prometheus.BuildFQName(types.Namespace, Name, "mtime_timestamp_seconds"),
+		"File modification time",
+		[]string{"file"},
+		nil,
+	)
+
+	for _, filePattern := range c.config.filePatterns {
+		basePath, pattern := doublestar.SplitPattern(filePattern)
+
+		_, err := doublestar.Glob(os.DirFS(basePath), pattern, doublestar.WithFilesOnly())
+		if err != nil {
+			return fmt.Errorf("invalid glob pattern: %w", err)
+		}
+	}
+
+	return nil
+}
+
+// Collect sends the metric values for each metric
+// to the provided prometheus Metric channel.
+func (c *Collector) Collect(_ *types.ScrapeContext, logger *slog.Logger, ch chan<- prometheus.Metric) error {
+	logger = logger.With(slog.String("collector", Name))
+
+	return c.collectGlob(logger, ch)
+}
+
+// collectWin32 collects file times for each file path in the config. It using Win32 FindFirstFile and FindNextFile.
+func (c *Collector) collectGlob(logger *slog.Logger, ch chan<- prometheus.Metric) error {
+	wg := sync.WaitGroup{}
+
+	for _, filePattern := range c.config.filePatterns {
+		wg.Add(1)
+
+		go func(filePattern string) {
+			defer wg.Done()
+
+			if err := c.collectGlobFilePath(logger, ch, filePattern); err != nil {
+				logger.Error("failed collecting metrics for filepath",
+					slog.String("filepath", filePattern),
+					slog.Any("err", err),
+				)
+			}
+		}(filePattern)
+	}
+
+	wg.Wait()
+
+	return nil
+}
+
+func (c *Collector) collectGlobFilePath(logger *slog.Logger, ch chan<- prometheus.Metric, filePattern string) error {
+	basePath, pattern := doublestar.SplitPattern(filePattern)
+	basePathFS := os.DirFS(basePath)
+
+	matches, err := doublestar.Glob(basePathFS, pattern, doublestar.WithFilesOnly())
+	if err != nil {
+		return fmt.Errorf("failed to glob: %w", err)
+	}
+
+	for _, match := range matches {
+		filePath := filepath.Join(basePath, match)
+
+		fileInfo, err := os.Stat(filePath)
+		if err != nil {
+			logger.Warn("failed to state file",
+				slog.String("file", filePath),
+				slog.Any("err", err),
+			)
+
+			continue
+		}
+
+		ch <- prometheus.MustNewConstMetric(
+			c.fileMTime,
+			prometheus.GaugeValue,
+			float64(fileInfo.ModTime().UTC().Unix()),
+			filePath,
+		)
+	}
+
+	return nil
+}

pkg/collector/filetime/filetime_test.go

@@ -0,0 +1,12 @@
+package filetime_test
+
+import (
+	"testing"
+
+	"github.com/prometheus-community/windows_exporter/pkg/collector/filetime"
+	"github.com/prometheus-community/windows_exporter/pkg/testutils"
+)
+
+func BenchmarkCollector(b *testing.B) {
+	testutils.FuncBenchmarkCollector(b, filetime.Name, filetime.NewWithFlags)
+}

pkg/collector/map.go

@@ -18,6 +18,7 @@ import (
 	"github.com/prometheus-community/windows_exporter/pkg/collector/diskdrive"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/dns"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/exchange"
+	"github.com/prometheus-community/windows_exporter/pkg/collector/filetime"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/fsrmquota"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/hyperv"
 	"github.com/prometheus-community/windows_exporter/pkg/collector/iis"
@@ -73,6 +74,7 @@ var BuildersWithFlags = map[string]BuilderWithFlags[Collector]{
 	diskdrive.Name:         NewBuilderWithFlags(diskdrive.NewWithFlags),
 	dns.Name:               NewBuilderWithFlags(dns.NewWithFlags),
 	exchange.Name:          NewBuilderWithFlags(exchange.NewWithFlags),
+	filetime.Name:          NewBuilderWithFlags(filetime.NewWithFlags),
 	fsrmquota.Name:         NewBuilderWithFlags(fsrmquota.NewWithFlags),
 	hyperv.Name:            NewBuilderWithFlags(hyperv.NewWithFlags),
 	iis.Name:               NewBuilderWithFlags(iis.NewWithFlags),