windows_exporter/internal/collector/service/service.go

475 lines
12 KiB
Go

//go:build windows
package service
import (
"errors"
"fmt"
"log/slog"
"regexp"
"strconv"
"sync"
"unsafe"
"github.com/alecthomas/kingpin/v2"
"github.com/prometheus-community/windows_exporter/internal/mi"
"github.com/prometheus-community/windows_exporter/internal/types"
"github.com/prometheus/client_golang/prometheus"
"golang.org/x/sys/windows"
"golang.org/x/sys/windows/svc/mgr"
)
const Name = "service"
type Config struct {
ServiceInclude *regexp.Regexp `yaml:"service_include"`
ServiceExclude *regexp.Regexp `yaml:"service_exclude"`
}
var ConfigDefaults = Config{
ServiceInclude: types.RegExpAny,
ServiceExclude: types.RegExpEmpty,
}
// A Collector is a Prometheus Collector for service metrics.
type Collector struct {
config Config
logger *slog.Logger
apiStateValues map[uint32]string
apiStartModeValues map[uint32]string
state *prometheus.Desc
processID *prometheus.Desc
info *prometheus.Desc
startMode *prometheus.Desc
// serviceConfigPoolBytes is a pool of byte slices used to avoid allocations
// ref: https://victoriametrics.com/blog/go-sync-pool/
serviceConfigPoolBytes sync.Pool
serviceManagerHandle *mgr.Mgr
}
func New(config *Config) *Collector {
if config == nil {
config = &ConfigDefaults
}
if config.ServiceExclude == nil {
config.ServiceExclude = ConfigDefaults.ServiceExclude
}
if config.ServiceInclude == nil {
config.ServiceInclude = ConfigDefaults.ServiceInclude
}
c := &Collector{
config: *config,
}
return c
}
func NewWithFlags(app *kingpin.Application) *Collector {
c := &Collector{
config: ConfigDefaults,
}
var serviceExclude, serviceInclude string
app.Flag(
"collector.service.exclude",
"Regexp of service to exclude. Service name (not the display name!) must both match include and not match exclude to be included.",
).Default("").StringVar(&serviceExclude)
app.Flag(
"collector.service.include",
"Regexp of service to include. Process name (not the display name!) must both match include and not match exclude to be included.",
).Default(".+").StringVar(&serviceInclude)
app.Action(func(*kingpin.ParseContext) error {
var err error
c.config.ServiceExclude, err = regexp.Compile(fmt.Sprintf("^(?:%s)$", serviceExclude))
if err != nil {
return fmt.Errorf("collector.process.exclude: %w", err)
}
c.config.ServiceInclude, err = regexp.Compile(fmt.Sprintf("^(?:%s)$", serviceInclude))
if err != nil {
return fmt.Errorf("collector.process.include: %w", err)
}
return nil
})
return c
}
func (c *Collector) GetName() string {
return Name
}
func (c *Collector) Build(logger *slog.Logger, _ *mi.Session) error {
c.logger = logger.With(slog.String("collector", Name))
if c.config.ServiceInclude.String() == "^(?:.*)$" && c.config.ServiceExclude.String() == "^(?:)$" {
c.logger.Warn("No filters specified for service collector. This will generate a very large number of metrics!")
}
c.serviceConfigPoolBytes = sync.Pool{
New: func() any {
return new([]byte)
},
}
c.info = prometheus.NewDesc(
prometheus.BuildFQName(types.Namespace, Name, "info"),
"A metric with a constant '1' value labeled with service information",
[]string{"name", "display_name", "run_as", "path_name"},
nil,
)
c.state = prometheus.NewDesc(
prometheus.BuildFQName(types.Namespace, Name, "state"),
"The state of the service (State)",
[]string{"name", "state"},
nil,
)
c.startMode = prometheus.NewDesc(
prometheus.BuildFQName(types.Namespace, Name, "start_mode"),
"The start mode of the service (StartMode)",
[]string{"name", "start_mode"},
nil,
)
c.processID = prometheus.NewDesc(
prometheus.BuildFQName(types.Namespace, Name, "process"),
"Process of started service. The value is the creation time of the process as a unix timestamp.",
[]string{"name", "process_id"},
nil,
)
c.apiStateValues = map[uint32]string{
windows.SERVICE_CONTINUE_PENDING: "continue pending",
windows.SERVICE_PAUSE_PENDING: "pause pending",
windows.SERVICE_PAUSED: "paused",
windows.SERVICE_RUNNING: "running",
windows.SERVICE_START_PENDING: "start pending",
windows.SERVICE_STOP_PENDING: "stop pending",
windows.SERVICE_STOPPED: "stopped",
}
c.apiStartModeValues = map[uint32]string{
windows.SERVICE_AUTO_START: "auto",
windows.SERVICE_BOOT_START: "boot",
windows.SERVICE_DEMAND_START: "manual",
windows.SERVICE_DISABLED: "disabled",
windows.SERVICE_SYSTEM_START: "system",
}
// EnumServiceStatusEx requires only SC_MANAGER_ENUM_SERVICE.
handle, err := windows.OpenSCManager(nil, nil, windows.SC_MANAGER_ENUMERATE_SERVICE)
if err != nil {
return fmt.Errorf("failed to open scm: %w", err)
}
c.serviceManagerHandle = &mgr.Mgr{Handle: handle}
return nil
}
func (c *Collector) Close() error {
if err := c.serviceManagerHandle.Disconnect(); err != nil {
c.logger.Warn("Failed to disconnect from scm",
slog.Any("err", err),
)
}
return nil
}
// Collect sends the metric values for each metric
// to the provided prometheus Metric channel.
func (c *Collector) Collect(ch chan<- prometheus.Metric) error {
services, err := c.queryAllServices()
if err != nil {
return fmt.Errorf("failed to query services: %w", err)
}
if len(services) == 0 {
c.logger.Warn("No services queried")
return nil
}
servicesCh := make(chan windows.ENUM_SERVICE_STATUS_PROCESS, len(services))
wg := sync.WaitGroup{}
wg.Add(len(services))
for range 4 {
go func(ch chan<- prometheus.Metric, wg *sync.WaitGroup) {
for service := range servicesCh {
c.collectWorker(ch, service)
wg.Done()
}
}(ch, &wg)
}
for _, service := range services {
servicesCh <- service
}
close(servicesCh)
wg.Wait()
return nil
}
func (c *Collector) collectWorker(ch chan<- prometheus.Metric, service windows.ENUM_SERVICE_STATUS_PROCESS) {
serviceName := windows.UTF16PtrToString(service.ServiceName)
if c.config.ServiceExclude.MatchString(serviceName) || !c.config.ServiceInclude.MatchString(serviceName) {
return
}
if err := c.collectService(ch, serviceName, service); err != nil {
c.logger.Warn("failed collecting service info",
slog.Any("err", err),
slog.String("service", serviceName),
)
}
}
func (c *Collector) collectService(ch chan<- prometheus.Metric, serviceName string, service windows.ENUM_SERVICE_STATUS_PROCESS) error {
// Open connection for service handler.
serviceHandle, err := windows.OpenService(c.serviceManagerHandle.Handle, service.ServiceName, windows.SERVICE_QUERY_CONFIG)
if err != nil {
return fmt.Errorf("failed to open service: %w", err)
}
// Create handle for each service.
serviceManager := &mgr.Service{Name: serviceName, Handle: serviceHandle}
defer func(serviceManager *mgr.Service) {
if err := serviceManager.Close(); err != nil {
c.logger.Warn("failed to close service handle",
slog.Any("err", err),
slog.String("service", serviceName),
)
}
}(serviceManager)
// Get Service Configuration.
serviceConfig, err := c.getServiceConfig(serviceManager)
if err != nil {
if !errors.Is(err, windows.ERROR_FILE_NOT_FOUND) && !errors.Is(err, windows.ERROR_MUI_FILE_NOT_FOUND) {
return fmt.Errorf("failed to get service configuration: %w", err)
}
c.logger.Debug("failed collecting service config",
slog.Any("err", err),
slog.String("service", serviceName),
)
}
ch <- prometheus.MustNewConstMetric(
c.info,
prometheus.GaugeValue,
1.0,
serviceName,
serviceConfig.DisplayName,
serviceConfig.ServiceStartName,
serviceConfig.BinaryPathName,
)
var (
isCurrentStartMode float64
isCurrentState float64
)
for _, startMode := range c.apiStartModeValues {
isCurrentStartMode = 0.0
if startMode == c.apiStartModeValues[serviceConfig.StartType] {
isCurrentStartMode = 1.0
}
ch <- prometheus.MustNewConstMetric(
c.startMode,
prometheus.GaugeValue,
isCurrentStartMode,
serviceName,
startMode,
)
}
for state, stateValue := range c.apiStateValues {
isCurrentState = 0.0
if state == service.ServiceStatusProcess.CurrentState {
isCurrentState = 1.0
}
ch <- prometheus.MustNewConstMetric(
c.state,
prometheus.GaugeValue,
isCurrentState,
serviceName,
stateValue,
)
}
if service.ServiceStatusProcess.ProcessId == 0 {
return nil
}
processID := strconv.FormatUint(uint64(service.ServiceStatusProcess.ProcessId), 10)
processStartTime, err := c.getProcessStartTime(service.ServiceStatusProcess.ProcessId)
if err == nil {
ch <- prometheus.MustNewConstMetric(
c.processID,
prometheus.GaugeValue,
float64(processStartTime/1_000_000_000),
serviceName,
processID,
)
return nil
}
if errors.Is(err, windows.ERROR_ACCESS_DENIED) {
c.logger.Debug("failed to get process start time",
slog.String("service", serviceName),
slog.Any("err", err),
)
} else {
c.logger.Warn("failed to get process start time",
slog.String("service", serviceName),
slog.Any("err", err),
)
}
return nil
}
// queryAllServices returns all service states of the current Windows system
// This is realized by ask Service Manager directly.
func (c *Collector) queryAllServices() ([]windows.ENUM_SERVICE_STATUS_PROCESS, error) {
var (
bytesNeeded uint32
servicesReturned uint32
err error
)
buf := make([]byte, 1024*100)
for {
err = windows.EnumServicesStatusEx(
c.serviceManagerHandle.Handle,
windows.SC_STATUS_PROCESS_INFO,
windows.SERVICE_WIN32,
windows.SERVICE_STATE_ALL,
&buf[0],
uint32(len(buf)),
&bytesNeeded,
&servicesReturned,
nil,
nil,
)
if err == nil {
break
}
if !errors.Is(err, windows.ERROR_MORE_DATA) {
return nil, err
}
if bytesNeeded <= uint32(len(buf)) {
return nil, err
}
buf = make([]byte, bytesNeeded)
}
if servicesReturned == 0 {
return []windows.ENUM_SERVICE_STATUS_PROCESS{}, nil
}
services := unsafe.Slice((*windows.ENUM_SERVICE_STATUS_PROCESS)(unsafe.Pointer(&buf[0])), int(servicesReturned))
return services, nil
}
func (c *Collector) getProcessStartTime(pid uint32) (uint64, error) {
handle, err := windows.OpenProcess(windows.PROCESS_QUERY_LIMITED_INFORMATION, false, pid)
if err != nil {
return 0, fmt.Errorf("failed to open process %w", err)
}
defer func(handle windows.Handle) {
err := windows.CloseHandle(handle)
if err != nil {
c.logger.Warn("failed to close process handle",
slog.Any("err", err),
)
}
}(handle)
var (
creation windows.Filetime
exit windows.Filetime
krn windows.Filetime
user windows.Filetime
)
err = windows.GetProcessTimes(handle, &creation, &exit, &krn, &user)
if err != nil {
return 0, fmt.Errorf("failed to get process times %w", err)
}
return uint64(creation.Nanoseconds()), nil
}
// getServiceConfig is an optimized variant of [mgr.Service] that only
// retrieves the necessary information.
func (c *Collector) getServiceConfig(service *mgr.Service) (mgr.Config, error) {
var serviceConfig *windows.QUERY_SERVICE_CONFIG
bytesNeeded := uint32(1024)
buf, ok := c.serviceConfigPoolBytes.Get().(*[]byte)
if !ok || len(*buf) == 0 {
*buf = make([]byte, bytesNeeded)
} else {
bytesNeeded = uint32(cap(*buf))
}
for {
serviceConfig = (*windows.QUERY_SERVICE_CONFIG)(unsafe.Pointer(&(*buf)[0]))
err := windows.QueryServiceConfig(service.Handle, serviceConfig, bytesNeeded, &bytesNeeded)
if err == nil {
break
}
if !errors.Is(err, windows.ERROR_INSUFFICIENT_BUFFER) && !errors.Is(err, windows.ERROR_MORE_DATA) {
return mgr.Config{}, err
}
if bytesNeeded <= uint32(len(*buf)) {
return mgr.Config{}, fmt.Errorf("win32 reports buffer too small (%d), but buffer is large enough (%d): %w", uint32(cap(*buf)), bytesNeeded, err)
}
*buf = make([]byte, bytesNeeded)
}
c.serviceConfigPoolBytes.Put(buf)
return mgr.Config{
BinaryPathName: windows.UTF16PtrToString(serviceConfig.BinaryPathName),
DisplayName: windows.UTF16PtrToString(serviceConfig.DisplayName),
StartType: serviceConfig.StartType,
ServiceStartName: windows.UTF16PtrToString(serviceConfig.ServiceStartName),
}, nil
}