chore: move exporter binary to cmd package (#1768)

Signed-off-by: Jan-Otto Kröpke <mail@jkroepke.de>
2026-02-24 05:36:36 +00:00 · 2024-11-24 15:53:56 +01:00
parent 1badb34506
commit eff124250f
12 changed files with 395 additions and 114 deletions
--- a/cmd/windows_exporter/main.go
+++ b/cmd/windows_exporter/main.go
@@ -0,0 +1,348 @@
+// Copyright 2024 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build windows
+
+//go:generate go run github.com/tc-hib/go-winres@v0.3.3 make --product-version=git-tag --file-version=git-tag --arch=amd64,arm64
+
+package main
+
+//goland:noinspection GoUnsortedImport
+//nolint:gofumpt
+import (
+	// Its important that we do these first so that we can register with the Windows service control ASAP to avoid timeouts.
+	"github.com/prometheus-community/windows_exporter/internal/windowsservice"
+
+	"context"
+	"errors"
+	"fmt"
+	"log/slog"
+	"net/http"
+	"net/http/pprof"
+	"os"
+	"os/signal"
+	"os/user"
+	"runtime"
+	"slices"
+	"strings"
+	"time"
+
+	"github.com/alecthomas/kingpin/v2"
+	"github.com/prometheus-community/windows_exporter/internal/config"
+	"github.com/prometheus-community/windows_exporter/internal/httphandler"
+	"github.com/prometheus-community/windows_exporter/internal/log"
+	"github.com/prometheus-community/windows_exporter/internal/log/flag"
+	"github.com/prometheus-community/windows_exporter/pkg/collector"
+	"github.com/prometheus/common/version"
+	"github.com/prometheus/exporter-toolkit/web"
+	webflag "github.com/prometheus/exporter-toolkit/web/kingpinflag"
+	"golang.org/x/sys/windows"
+)
+
+func main() {
+	exitCode := run()
+
+	// If we are running as a service, we need to signal the service control manager that we are done.
+	if !windowsservice.IsService {
+		os.Exit(exitCode)
+	}
+
+	windowsservice.ExitCodeCh <- exitCode
+
+	// Wait for the service control manager to signal that we are done.
+	<-windowsservice.StopCh
+}
+
+func run() int {
+	app := kingpin.New("windows_exporter", "A metrics collector for Windows.")
+
+	var (
+		configFile = app.Flag(
+			"config.file",
+			"YAML configuration file to use. Values set in this file will be overridden by CLI flags.",
+		).String()
+		insecureSkipVerify = app.Flag(
+			"config.file.insecure-skip-verify",
+			"Skip TLS verification in loading YAML configuration.",
+		).Default("false").Bool()
+		webConfig   = webflag.AddFlags(app, ":9182")
+		metricsPath = app.Flag(
+			"telemetry.path",
+			"URL path for surfacing collected metrics.",
+		).Default("/metrics").String()
+		disableExporterMetrics = app.Flag(
+			"web.disable-exporter-metrics",
+			"Exclude metrics about the exporter itself (promhttp_*, process_*, go_*).",
+		).Bool()
+		maxRequests = app.Flag(
+			"telemetry.max-requests",
+			"Maximum number of concurrent requests. 0 to disable.",
+		).Default("5").Int()
+		enabledCollectors = app.Flag(
+			"collectors.enabled",
+			"Comma-separated list of collectors to use. Use '[defaults]' as a placeholder for all the collectors enabled by default.").
+			Default(collector.DefaultCollectors).String()
+		timeoutMargin = app.Flag(
+			"scrape.timeout-margin",
+			"Seconds to subtract from the timeout allowed by the client. Tune to allow for overhead or high loads.",
+		).Default("0.5").Float64()
+		debugEnabled = app.Flag(
+			"debug.enabled",
+			"If true, windows_exporter will expose debug endpoints under /debug/pprof.",
+		).Default("false").Bool()
+		processPriority = app.Flag(
+			"process.priority",
+			"Priority of the exporter process. Higher priorities may improve exporter responsiveness during periods of system load. Can be one of [\"realtime\", \"high\", \"abovenormal\", \"normal\", \"belownormal\", \"low\"]",
+		).Default("normal").String()
+	)
+
+	logConfig := &log.Config{}
+	flag.AddFlags(app, logConfig)
+
+	app.Version(version.Print("windows_exporter"))
+	app.HelpFlag.Short('h')
+
+	// Initialize collectors before loading and parsing CLI arguments
+	collectors := collector.NewWithFlags(app)
+
+	// Load values from configuration file(s). Executable flags must first be parsed, in order
+	// to load the specified file(s).
+	if _, err := app.Parse(os.Args[1:]); err != nil {
+		//nolint:sloglint // we do not have an logger yet
+		slog.Error("Failed to parse CLI args",
+			slog.Any("err", err),
+		)
+
+		return 1
+	}
+
+	logger, err := log.New(logConfig)
+	if err != nil {
+		//nolint:sloglint // we do not have an logger yet
+		slog.Error("failed to create logger",
+			slog.Any("err", err),
+		)
+
+		return 1
+	}
+
+	if *configFile != "" {
+		resolver, err := config.NewResolver(*configFile, logger, *insecureSkipVerify)
+		if err != nil {
+			logger.Error("could not load config file",
+				slog.Any("err", err),
+			)
+
+			return 1
+		}
+
+		if err = resolver.Bind(app, os.Args[1:]); err != nil {
+			logger.Error("Failed to bind configuration",
+				slog.Any("err", err),
+			)
+
+			return 1
+		}
+
+		// NOTE: This is temporary fix for issue #1092, calling kingpin.Parse
+		// twice makes slices flags duplicate its value, this clean up
+		// the first parse before the second call.
+		*webConfig.WebListenAddresses = (*webConfig.WebListenAddresses)[1:]
+
+		// Parse flags once more to include those discovered in configuration file(s).
+		if _, err = app.Parse(os.Args[1:]); err != nil {
+			logger.Error("Failed to parse CLI args from YAML file",
+				slog.Any("err", err),
+			)
+
+			return 1
+		}
+
+		logger, err = log.New(logConfig)
+		if err != nil {
+			//nolint:sloglint // we do not have an logger yet
+			slog.Error("failed to create logger",
+				slog.Any("err", err),
+			)
+
+			return 1
+		}
+	}
+
+	logger.Debug("Logging has Started")
+
+	if err = setPriorityWindows(logger, os.Getpid(), *processPriority); err != nil {
+		logger.Error("failed to set process priority",
+			slog.Any("err", err),
+		)
+
+		return 1
+	}
+
+	enabledCollectorList := expandEnabledCollectors(*enabledCollectors)
+	if err := collectors.Enable(enabledCollectorList); err != nil {
+		logger.Error("Couldn't enable collectors",
+			slog.Any("err", err),
+		)
+
+		return 1
+	}
+
+	// Initialize collectors before loading
+	if err = collectors.Build(logger); err != nil {
+		logger.Error("Couldn't load collectors",
+			slog.Any("err", err),
+		)
+
+		return 1
+	}
+
+	logCurrentUser(logger)
+
+	logger.Info("Enabled collectors: " + strings.Join(enabledCollectorList, ", "))
+
+	mux := http.NewServeMux()
+	mux.Handle("GET /health", httphandler.NewHealthHandler())
+	mux.Handle("GET /version", httphandler.NewVersionHandler())
+	mux.Handle("GET "+*metricsPath, httphandler.New(logger, collectors, &httphandler.Options{
+		DisableExporterMetrics: *disableExporterMetrics,
+		TimeoutMargin:          *timeoutMargin,
+		MaxRequests:            *maxRequests,
+	}))
+
+	if *debugEnabled {
+		mux.HandleFunc("GET /debug/pprof/", pprof.Index)
+		mux.HandleFunc("GET /debug/pprof/cmdline", pprof.Cmdline)
+		mux.HandleFunc("GET /debug/pprof/profile", pprof.Profile)
+		mux.HandleFunc("GET /debug/pprof/symbol", pprof.Symbol)
+		mux.HandleFunc("GET /debug/pprof/trace", pprof.Trace)
+	}
+
+	logger.Info("Starting windows_exporter",
+		slog.String("version", version.Version),
+		slog.String("branch", version.Branch),
+		slog.String("revision", version.GetRevision()),
+		slog.String("goversion", version.GoVersion),
+		slog.String("builddate", version.BuildDate),
+		slog.Int("maxprocs", runtime.GOMAXPROCS(0)),
+	)
+
+	server := &http.Server{
+		ReadHeaderTimeout: 5 * time.Second,
+		IdleTimeout:       60 * time.Second,
+		ReadTimeout:       5 * time.Second,
+		WriteTimeout:      5 * time.Minute,
+		Handler:           mux,
+	}
+
+	errCh := make(chan error, 1)
+
+	go func() {
+		if err := web.ListenAndServe(server, webConfig, logger); err != nil && !errors.Is(err, http.ErrServerClosed) {
+			errCh <- err
+		}
+
+		close(errCh)
+	}()
+
+	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, os.Kill)
+	defer stop()
+
+	select {
+	case <-ctx.Done():
+		logger.Info("Shutting down windows_exporter via kill signal")
+	case <-windowsservice.StopCh:
+		logger.Info("Shutting down windows_exporter via service control")
+	case err := <-errCh:
+		if err != nil {
+			logger.Error("Failed to start windows_exporter",
+				slog.Any("err", err),
+			)
+
+			return 1
+		}
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	_ = server.Shutdown(ctx)
+
+	logger.Info("windows_exporter has shut down")
+
+	return 0
+}
+
+func logCurrentUser(logger *slog.Logger) {
+	u, err := user.Current()
+	if err != nil {
+		logger.Warn("Unable to determine which user is running this exporter. More info: https://github.com/golang/go/issues/37348",
+			slog.Any("err", err),
+		)
+
+		return
+	}
+
+	logger.Info("Running as " + u.Username)
+
+	if strings.Contains(u.Username, "ContainerAdministrator") || strings.Contains(u.Username, "ContainerUser") {
+		logger.Warn("Running as a preconfigured Windows Container user. This may mean you do not have Windows HostProcess containers configured correctly and some functionality will not work as expected.")
+	}
+}
+
+// setPriorityWindows sets the priority of the current process to the specified value.
+func setPriorityWindows(logger *slog.Logger, pid int, priority string) error {
+	// Mapping of priority names to uin32 values required by windows.SetPriorityClass.
+	priorityStringToInt := map[string]uint32{
+		"realtime":    windows.REALTIME_PRIORITY_CLASS,
+		"high":        windows.HIGH_PRIORITY_CLASS,
+		"abovenormal": windows.ABOVE_NORMAL_PRIORITY_CLASS,
+		"normal":      windows.NORMAL_PRIORITY_CLASS,
+		"belownormal": windows.BELOW_NORMAL_PRIORITY_CLASS,
+		"low":         windows.IDLE_PRIORITY_CLASS,
+	}
+
+	winPriority, ok := priorityStringToInt[priority]
+
+	// Only set process priority if a non-default and valid value has been set
+	if !ok || winPriority != windows.NORMAL_PRIORITY_CLASS {
+		return nil
+	}
+
+	logger.Debug("setting process priority to " + priority)
+
+	// https://learn.microsoft.com/en-us/windows/win32/procthread/process-security-and-access-rights
+	handle, err := windows.OpenProcess(
+		windows.STANDARD_RIGHTS_REQUIRED|windows.SYNCHRONIZE|windows.SPECIFIC_RIGHTS_ALL,
+		false, uint32(pid),
+	)
+	if err != nil {
+		return fmt.Errorf("failed to open own process: %w", err)
+	}
+
+	if err = windows.SetPriorityClass(handle, winPriority); err != nil {
+		return fmt.Errorf("failed to set priority class: %w", err)
+	}
+
+	if err = windows.CloseHandle(handle); err != nil {
+		return fmt.Errorf("failed to close handle: %w", err)
+	}
+
+	return nil
+}
+
+func expandEnabledCollectors(enabled string) []string {
+	expanded := strings.ReplaceAll(enabled, "[defaults]", collector.DefaultCollectors)
+
+	return slices.Compact(strings.Split(expanded, ","))
+}