windows_exporter/exporter.go

252 lines
8.2 KiB
Go

//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
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/pkg/initiate"
"encoding/json"
"fmt"
"net/http"
"net/http/pprof"
"os"
"os/user"
"runtime"
"sort"
"strings"
winlog "github.com/prometheus-community/windows_exporter/pkg/log"
"github.com/prometheus-community/windows_exporter/pkg/types"
"github.com/prometheus-community/windows_exporter/pkg/utils"
"github.com/prometheus-community/windows_exporter/pkg/wmi"
"github.com/alecthomas/kingpin/v2"
"github.com/go-kit/log/level"
"github.com/prometheus-community/windows_exporter/pkg/collector"
"github.com/prometheus-community/windows_exporter/pkg/config"
"github.com/prometheus-community/windows_exporter/pkg/log/flag"
"github.com/prometheus/common/version"
"github.com/prometheus/exporter-toolkit/web"
webflag "github.com/prometheus/exporter-toolkit/web/kingpinflag"
)
// Same struct prometheus uses for their /version endpoint.
// Separate copy to avoid pulling all of prometheus as a dependency
type prometheusVersion struct {
Version string `json:"version"`
Revision string `json:"revision"`
Branch string `json:"branch"`
BuildUser string `json:"buildUser"`
BuildDate string `json:"buildDate"`
GoVersion string `json:"goVersion"`
}
func main() {
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()
insecure_skip_verify = 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(types.DefaultCollectors).String()
printCollectors = app.Flag(
"collectors.print",
"If true, print available collectors and exit.",
).Bool()
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()
)
winlogConfig := &winlog.Config{}
flag.AddFlags(app, winlogConfig)
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).
kingpin.MustParse(app.Parse(os.Args[1:]))
logger, err := winlog.New(winlogConfig)
if err != nil {
_ = level.Error(logger).Log("err", err)
os.Exit(1)
}
_ = level.Debug(logger).Log("msg", "Logging has Started")
if *configFile != "" {
resolver, err := config.NewResolver(*configFile, logger, *insecure_skip_verify)
if err != nil {
_ = level.Error(logger).Log("msg", "could not load config file", "err", err)
os.Exit(1)
}
err = resolver.Bind(app, os.Args[1:])
if err != nil {
_ = level.Error(logger).Log("err", err)
os.Exit(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).
kingpin.MustParse(app.Parse(os.Args[1:]))
logger, err = winlog.New(winlogConfig)
if err != nil {
_ = level.Error(logger).Log("err", err)
os.Exit(1)
}
}
if *printCollectors {
collectorNames := collector.Available()
sort.Strings(collectorNames)
fmt.Printf("Available collectors:\n")
for _, n := range collectorNames {
fmt.Printf(" - %s\n", n)
}
return
}
if err = wmi.InitWbem(logger); err != nil {
_ = level.Error(logger).Log("err", err)
os.Exit(1)
}
enabledCollectorList := utils.ExpandEnabledCollectors(*enabledCollectors)
collectors.Enable(enabledCollectorList)
collectors.SetLogger(logger)
// Initialize collectors before loading
err = collectors.Build()
if err != nil {
_ = level.Error(logger).Log("msg", "Couldn't load collectors", "err", err)
os.Exit(1)
}
err = collectors.SetPerfCounterQuery()
if err != nil {
_ = level.Error(logger).Log("msg", "Couldn't set performance counter query", "err", err)
os.Exit(1)
}
if u, err := user.Current(); err != nil {
_ = level.Warn(logger).Log("msg", "Unable to determine which user is running this exporter. More info: https://github.com/golang/go/issues/37348")
} else {
_ = level.Info(logger).Log("msg", fmt.Sprintf("Running as %v", u.Username))
if strings.Contains(u.Username, "ContainerAdministrator") || strings.Contains(u.Username, "ContainerUser") {
_ = level.Warn(logger).Log("msg", "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.")
}
}
_ = level.Info(logger).Log("msg", fmt.Sprintf("Enabled collectors: %v", strings.Join(enabledCollectorList, ", ")))
mux := http.NewServeMux()
mux.HandleFunc(*metricsPath, withConcurrencyLimit(*maxRequests, collectors.BuildServeHTTP(*disableExporterMetrics, *timeoutMargin)))
mux.HandleFunc("/health", func(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "application/json")
_, err := fmt.Fprintln(w, `{"status":"ok"}`)
if err != nil {
_ = level.Debug(logger).Log("msg", "Failed to write to stream", "err", err)
}
})
mux.HandleFunc("/version", func(w http.ResponseWriter, r *http.Request) {
// we can't use "version" directly as it is a package, and not an object that
// can be serialized.
err := json.NewEncoder(w).Encode(prometheusVersion{
Version: version.Version,
Revision: version.Revision,
Branch: version.Branch,
BuildUser: version.BuildUser,
BuildDate: version.BuildDate,
GoVersion: version.GoVersion,
})
if err != nil {
http.Error(w, fmt.Sprintf("error encoding JSON: %s", err), http.StatusInternalServerError)
}
})
if *debugEnabled {
mux.HandleFunc("/debug/pprof/", pprof.Index)
mux.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
mux.HandleFunc("/debug/pprof/profile", pprof.Profile)
mux.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
mux.HandleFunc("/debug/pprof/trace", pprof.Trace)
}
_ = level.Info(logger).Log("msg", "Starting windows_exporter", "version", version.Info())
_ = level.Info(logger).Log("msg", "Build context", "build_context", version.BuildContext())
_ = level.Debug(logger).Log("msg", "Go MAXPROCS", "procs", runtime.GOMAXPROCS(0))
go func() {
server := &http.Server{Handler: mux}
if err := web.ListenAndServe(server, webConfig, logger); err != nil {
_ = level.Error(logger).Log("msg", "cannot start windows_exporter", "err", err)
os.Exit(1)
}
}()
for {
if <-initiate.StopCh {
_ = level.Info(logger).Log("msg", "Shutting down windows_exporter")
break
}
}
}
func withConcurrencyLimit(n int, next http.HandlerFunc) http.HandlerFunc {
if n <= 0 {
return next
}
sem := make(chan struct{}, n)
return func(w http.ResponseWriter, r *http.Request) {
select {
case sem <- struct{}{}:
defer func() { <-sem }()
default:
w.WriteHeader(http.StatusServiceUnavailable)
_, _ = w.Write([]byte("Too many concurrent requests"))
return
}
next(w, r)
}
}