[#541] Use default value if config param is unset after SIGHUP

Signed-off-by: Marina Biryukova <m.biryukova@yadro.com>

cmd/s3-gw/app.go

@@ -64,7 +64,7 @@ type (
 	App struct {
 		ctr      s3middleware.Center
 		log      *zap.Logger
-		cfg      *viper.Viper
+		cfg      *appCfg
 		pool     *pool.Pool
 		treePool *treepool.Pool
 		key      *keys.PrivateKey
@@ -132,14 +132,14 @@ type (
 	}
 )
 
-func newApp(ctx context.Context, log *Logger, v *viper.Viper) *App {
+func newApp(ctx context.Context, log *Logger, cfg *appCfg) *App {
-	settings := newAppSettings(log, v)
+	settings := newAppSettings(log, cfg.config())
 
-	objPool, treePool, key := getPools(ctx, log.logger, v, settings.dialerSource)
+	objPool, treePool, key := getPools(ctx, log.logger, cfg.config(), settings.dialerSource)
 
 	app := &App{
 		log:      log.logger,
-		cfg:      v,
+		cfg:      cfg,
 		pool:     objPool,
 		treePool: treePool,
 		key:      key,
@@ -168,7 +168,7 @@ func (a *App) init(ctx context.Context) {
 }
 
 func (a *App) initAuthCenter(ctx context.Context) {
-	if a.cfg.IsSet(cfgContainersAccessBox) {
+	if a.cfg.config().IsSet(cfgContainersAccessBox) {
 		cnrID, err := a.resolveContainerID(ctx, cfgContainersAccessBox)
 		if err != nil {
 			a.log.Fatal(logs.CouldNotFetchAccessBoxContainerInfo, zap.Error(err))
@@ -179,11 +179,11 @@ func (a *App) initAuthCenter(ctx context.Context) {
 	cfg := tokens.Config{
 		FrostFS:                     frostfs.NewAuthmateFrostFS(frostfs.NewFrostFS(a.pool, a.key), a.log),
 		Key:                         a.key,
-		CacheConfig:                 getAccessBoxCacheConfig(a.cfg, a.log),
+		CacheConfig:                 getAccessBoxCacheConfig(a.cfg.config(), a.log),
-		RemovingCheckAfterDurations: fetchRemovingCheckInterval(a.cfg, a.log),
+		RemovingCheckAfterDurations: fetchRemovingCheckInterval(a.cfg.config(), a.log),
 	}
 
-	a.ctr = auth.New(tokens.New(cfg), a.cfg.GetStringSlice(cfgAllowedAccessKeyIDPrefixes), a.settings)
+	a.ctr = auth.New(tokens.New(cfg), a.cfg.config().GetStringSlice(cfgAllowedAccessKeyIDPrefixes), a.settings)
 }
 
 func (a *App) initLayer(ctx context.Context) {
@@ -197,7 +197,7 @@ func (a *App) initLayer(ctx context.Context) {
 	user.IDFromKey(&gateOwner, a.key.PrivateKey.PublicKey)
 
 	var corsCnrInfo *data.BucketInfo
-	if a.cfg.IsSet(cfgContainersCORS) {
+	if a.cfg.config().IsSet(cfgContainersCORS) {
 		corsCnrInfo, err = a.fetchContainerInfo(ctx, cfgContainersCORS)
 		if err != nil {
 			a.log.Fatal(logs.CouldNotFetchCORSContainerInfo, zap.Error(err))
@@ -205,7 +205,7 @@ func (a *App) initLayer(ctx context.Context) {
 	}
 
 	var lifecycleCnrInfo *data.BucketInfo
-	if a.cfg.IsSet(cfgContainersLifecycle) {
+	if a.cfg.config().IsSet(cfgContainersLifecycle) {
 		lifecycleCnrInfo, err = a.fetchContainerInfo(ctx, cfgContainersLifecycle)
 		if err != nil {
 			a.log.Fatal(logs.CouldNotFetchLifecycleContainerInfo, zap.Error(err))
@@ -213,7 +213,7 @@ func (a *App) initLayer(ctx context.Context) {
 	}
 
 	layerCfg := &layer.Config{
-		Cache: layer.NewCache(getCacheOptions(a.cfg, a.log)),
+		Cache: layer.NewCache(getCacheOptions(a.cfg.config(), a.log)),
 		AnonKey: layer.AnonymousKey{
 			Key: randomKey,
 		},
@@ -516,7 +516,7 @@ func (a *App) initMetrics() {
 		Logger:         a.log,
 		PoolStatistics: frostfs.NewPoolStatistic(a.pool),
 		TreeStatistic:  a.treePool,
-		Enabled:        a.cfg.GetBool(cfgPrometheusEnabled),
+		Enabled:        a.cfg.config().GetBool(cfgPrometheusEnabled),
 	}
 
 	a.metrics = metrics.NewAppMetrics(cfg)
@@ -525,9 +525,9 @@ func (a *App) initMetrics() {
 
 func (a *App) initFrostfsID(ctx context.Context) {
 	cli, err := ffidcontract.New(ctx, ffidcontract.Config{
-		RPCAddress:    a.cfg.GetString(cfgRPCEndpoint),
+		RPCAddress:    a.cfg.config().GetString(cfgRPCEndpoint),
-		Contract:      a.cfg.GetString(cfgFrostfsIDContract),
+		Contract:      a.cfg.config().GetString(cfgFrostfsIDContract),
-		ProxyContract: a.cfg.GetString(cfgProxyContract),
+		ProxyContract: a.cfg.config().GetString(cfgProxyContract),
 		Key:           a.key,
 		Waiter: commonclient.WaiterOptions{
 			IgnoreAlreadyExistsError: false,
@@ -539,7 +539,7 @@ func (a *App) initFrostfsID(ctx context.Context) {
 	}
 
 	a.frostfsid, err = frostfsid.NewFrostFSID(frostfsid.Config{
-		Cache:     cache.NewFrostfsIDCache(getFrostfsIDCacheConfig(a.cfg, a.log)),
+		Cache:     cache.NewFrostfsIDCache(getFrostfsIDCacheConfig(a.cfg.config(), a.log)),
 		FrostFSID: cli,
 		Logger:    a.log,
 	})
@@ -550,9 +550,9 @@ func (a *App) initFrostfsID(ctx context.Context) {
 
 func (a *App) initPolicyStorage(ctx context.Context) {
 	policyContract, err := contract.New(ctx, contract.Config{
-		RPCAddress:    a.cfg.GetString(cfgRPCEndpoint),
+		RPCAddress:    a.cfg.config().GetString(cfgRPCEndpoint),
-		Contract:      a.cfg.GetString(cfgPolicyContract),
+		Contract:      a.cfg.config().GetString(cfgPolicyContract),
-		ProxyContract: a.cfg.GetString(cfgProxyContract),
+		ProxyContract: a.cfg.config().GetString(cfgProxyContract),
 		Key:           a.key,
 		Waiter: commonclient.WaiterOptions{
 			IgnoreAlreadyExistsError: false,
@@ -565,7 +565,7 @@ func (a *App) initPolicyStorage(ctx context.Context) {
 
 	a.policyStorage = policy.NewStorage(policy.StorageConfig{
 		Contract: policyContract,
-		Cache:    cache.NewMorphPolicyCache(getMorphPolicyCacheConfig(a.cfg, a.log)),
+		Cache:    cache.NewMorphPolicyCache(getMorphPolicyCacheConfig(a.cfg.config(), a.log)),
 		Log:      a.log,
 	})
 }
@@ -581,13 +581,13 @@ func (a *App) initResolver() {
 func (a *App) getResolverConfig() *resolver.Config {
 	return &resolver.Config{
 		FrostFS:    frostfs.NewResolverFrostFS(a.pool),
-		RPCAddress: a.cfg.GetString(cfgRPCEndpoint),
+		RPCAddress: a.cfg.config().GetString(cfgRPCEndpoint),
 	}
 }
 
 func (a *App) getResolverOrder() []string {
-	order := a.cfg.GetStringSlice(cfgResolveOrder)
+	order := a.cfg.config().GetStringSlice(cfgResolveOrder)
-	if a.cfg.GetString(cfgRPCEndpoint) == "" {
+	if a.cfg.config().GetString(cfgRPCEndpoint) == "" {
 		order = remove(order, resolver.NNSResolver)
 		a.log.Warn(logs.ResolverNNSWontBeUsedSinceRPCEndpointIsntProvided)
 	}
@@ -605,15 +605,15 @@ func (a *App) initTracing(ctx context.Context) {
 		instanceID = a.servers[0].Address()
 	}
 	cfg := tracing.Config{
-		Enabled:    a.cfg.GetBool(cfgTracingEnabled),
+		Enabled:    a.cfg.config().GetBool(cfgTracingEnabled),
-		Exporter:   tracing.Exporter(a.cfg.GetString(cfgTracingExporter)),
+		Exporter:   tracing.Exporter(a.cfg.config().GetString(cfgTracingExporter)),
-		Endpoint:   a.cfg.GetString(cfgTracingEndpoint),
+		Endpoint:   a.cfg.config().GetString(cfgTracingEndpoint),
 		Service:    "frostfs-s3-gw",
 		InstanceID: instanceID,
 		Version:    version.Version,
 	}
 
-	if trustedCa := a.cfg.GetString(cfgTracingTrustedCa); trustedCa != "" {
+	if trustedCa := a.cfg.config().GetString(cfgTracingTrustedCa); trustedCa != "" {
 		caBytes, err := os.ReadFile(trustedCa)
 		if err != nil {
 			a.log.Warn(logs.FailedToInitializeTracing, zap.Error(err))
@@ -628,7 +628,7 @@ func (a *App) initTracing(ctx context.Context) {
 		cfg.ServerCaCertPool = certPool
 	}
 
-	attributes, err := fetchTracingAttributes(a.cfg)
+	attributes, err := fetchTracingAttributes(a.cfg.config())
 	if err != nil {
 		a.log.Warn(logs.FailedToInitializeTracing, zap.Error(err))
 		return
@@ -805,10 +805,10 @@ func (a *App) Serve(ctx context.Context) {
 	srv := new(http.Server)
 	srv.Handler = chiRouter
 	srv.ErrorLog = zap.NewStdLog(a.log)
-	srv.ReadTimeout = a.cfg.GetDuration(cfgWebReadTimeout)
+	srv.ReadTimeout = a.cfg.config().GetDuration(cfgWebReadTimeout)
-	srv.ReadHeaderTimeout = a.cfg.GetDuration(cfgWebReadHeaderTimeout)
+	srv.ReadHeaderTimeout = a.cfg.config().GetDuration(cfgWebReadHeaderTimeout)
-	srv.WriteTimeout = a.cfg.GetDuration(cfgWebWriteTimeout)
+	srv.WriteTimeout = a.cfg.config().GetDuration(cfgWebWriteTimeout)
-	srv.IdleTimeout = a.cfg.GetDuration(cfgWebIdleTimeout)
+	srv.IdleTimeout = a.cfg.config().GetDuration(cfgWebIdleTimeout)
 
 	a.startServices()
 
@@ -861,11 +861,11 @@ func shutdownContext() (context.Context, context.CancelFunc) {
 func (a *App) configReload(ctx context.Context) {
 	a.log.Info(logs.SIGHUPConfigReloadStarted)
 
-	if !a.cfg.IsSet(cmdConfig) && !a.cfg.IsSet(cmdConfigDir) {
+	if !a.cfg.config().IsSet(cmdConfig) && !a.cfg.config().IsSet(cmdConfigDir) {
 		a.log.Warn(logs.FailedToReloadConfigBecauseItsMissed)
 		return
 	}
-	if err := readInConfig(a.cfg); err != nil {
+	if err := a.cfg.reload(); err != nil {
 		a.log.Warn(logs.FailedToReloadConfig, zap.Error(err))
 		return
 	}
@@ -885,7 +885,7 @@ func (a *App) configReload(ctx context.Context) {
 
 	a.updateSettings()
 
-	a.metrics.SetEnabled(a.cfg.GetBool(cfgPrometheusEnabled))
+	a.metrics.SetEnabled(a.cfg.config().GetBool(cfgPrometheusEnabled))
 	a.initTracing(ctx)
 	a.setHealthStatus()
 
@@ -893,33 +893,33 @@ func (a *App) configReload(ctx context.Context) {
 }
 
 func (a *App) updateSettings() {
-	if lvl, err := getLogLevel(a.cfg); err != nil {
+	if lvl, err := getLogLevel(a.cfg.config()); err != nil {
 		a.log.Warn(logs.LogLevelWontBeUpdated, zap.Error(err))
 	} else {
 		a.settings.logLevel.SetLevel(lvl)
 	}
 
-	if err := a.settings.dialerSource.Update(fetchMultinetConfig(a.cfg, a.log)); err != nil {
+	if err := a.settings.dialerSource.Update(fetchMultinetConfig(a.cfg.config(), a.log)); err != nil {
 		a.log.Warn(logs.MultinetConfigWontBeUpdated, zap.Error(err))
 	}
 
-	a.settings.update(a.cfg, a.log)
+	a.settings.update(a.cfg.config(), a.log)
 }
 
 func (a *App) startServices() {
 	a.services = a.services[:0]
 
-	pprofService := NewPprofService(a.cfg, a.log)
+	pprofService := NewPprofService(a.cfg.config(), a.log)
 	a.services = append(a.services, pprofService)
 	go pprofService.Start()
 
-	prometheusService := NewPrometheusService(a.cfg, a.log, a.metrics.Handler())
+	prometheusService := NewPrometheusService(a.cfg.config(), a.log, a.metrics.Handler())
 	a.services = append(a.services, prometheusService)
 	go prometheusService.Start()
 }
 
 func (a *App) initServers(ctx context.Context) {
-	serversInfo := fetchServers(a.cfg, a.log)
+	serversInfo := fetchServers(a.cfg.config(), a.log)
 
 	a.servers = make([]Server, 0, len(serversInfo))
 	for _, serverInfo := range serversInfo {
@@ -946,7 +946,7 @@ func (a *App) initServers(ctx context.Context) {
 }
 
 func (a *App) updateServers() error {
-	serversInfo := fetchServers(a.cfg, a.log)
+	serversInfo := fetchServers(a.cfg.config(), a.log)
 
 	a.mu.Lock()
 	defer a.mu.Unlock()
@@ -1079,7 +1079,7 @@ func (a *App) setRuntimeParameters() {
 		return
 	}
 
-	softMemoryLimit := fetchSoftMemoryLimit(a.cfg)
+	softMemoryLimit := fetchSoftMemoryLimit(a.cfg.config())
 	previous := debug.SetMemoryLimit(softMemoryLimit)
 	if softMemoryLimit != previous {
 		a.log.Info(logs.RuntimeSoftMemoryLimitUpdated,
@@ -1155,7 +1155,7 @@ func (a *App) fetchContainerInfo(ctx context.Context, cfgKey string) (info *data
 }
 
 func (a *App) resolveContainerID(ctx context.Context, cfgKey string) (cid.ID, error) {
-	containerString := a.cfg.GetString(cfgKey)
+	containerString := a.cfg.config().GetString(cfgKey)
 
 	var id cid.ID
 	if err := id.DecodeString(containerString); err != nil {

cmd/s3-gw/app_settings.go

@@ -10,6 +10,7 @@ import (
 	"sort"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api"
@@ -286,6 +287,49 @@ var ignore = map[string]struct{}{
 	cmdVersion: {},
 }
 
+type appCfg struct {
+	flags *pflag.FlagSet
+
+	mu       sync.RWMutex
+	settings *viper.Viper
+}
+
+func (a *appCfg) reload() error {
+	old := a.config()
+
+	v, err := newViper(a.flags)
+	if err != nil {
+		return err
+	}
+
+	if old.IsSet(cmdConfig) {
+		v.Set(cmdConfig, old.Get(cmdConfig))
+	}
+	if old.IsSet(cmdConfigDir) {
+		v.Set(cmdConfigDir, old.Get(cmdConfigDir))
+	}
+
+	if err = readInConfig(v); err != nil {
+		return err
+	}
+
+	a.setConfig(v)
+	return nil
+}
+
+func (a *appCfg) config() *viper.Viper {
+	a.mu.RLock()
+	defer a.mu.RUnlock()
+
+	return a.settings
+}
+
+func (a *appCfg) setConfig(v *viper.Viper) {
+	a.mu.Lock()
+	a.settings = v
+	a.mu.Unlock()
+}
+
 func fetchConnectTimeout(cfg *viper.Viper) time.Duration {
 	connTimeout := cfg.GetDuration(cfgConnectTimeout)
 	if connTimeout <= 0 {
@@ -804,7 +848,7 @@ func fetchTracingAttributes(v *viper.Viper) (map[string]string, error) {
 	return attributes, nil
 }
 
-func newSettings() *viper.Viper {
+func newViper(flags *pflag.FlagSet) (*viper.Viper, error) {
 	v := viper.New()
 
 	v.AutomaticEnv()
@@ -813,6 +857,16 @@ func newSettings() *viper.Viper {
 	v.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
 	v.AllowEmptyEnv(true)
 
+	setDefaults(v, flags)
+
+	if v.IsSet(cfgServer+".0."+cfgTLSKeyFile) && v.IsSet(cfgServer+".0."+cfgTLSCertFile) {
+		v.Set(cfgServer+".0."+cfgTLSEnabled, true)
+	}
+
+	return v, bindFlags(v, flags)
+}
+
+func newSettings() *appCfg {
 	// flags setup:
 	flags := pflag.NewFlagSet("commandline", pflag.ExitOnError)
 	flags.SetOutput(os.Stdout)
@@ -840,15 +894,71 @@ func newSettings() *viper.Viper {
 	flags.String(cfgTLSCertFile, "", "TLS certificate file to use")
 	flags.String(cfgTLSKeyFile, "", "TLS key file to use")
 
-	peers := flags.StringArrayP(cfgPeers, "p", nil, "set FrostFS nodes")
+	flags.StringArrayP(cfgPeers, "p", nil, "set FrostFS nodes")
 
 	flags.StringP(cfgRPCEndpoint, "r", "", "set RPC endpoint")
-	resolveMethods := flags.StringSlice(cfgResolveOrder, []string{resolver.DNSResolver}, "set bucket name resolve order")
+	flags.StringSlice(cfgResolveOrder, []string{resolver.DNSResolver}, "set bucket name resolve order")
 
-	domains := flags.StringSliceP(cfgListenDomains, "d", nil, "set domains to be listened")
+	flags.StringSliceP(cfgListenDomains, "d", nil, "set domains to be listened")
 
-	// set defaults:
+	if err := flags.Parse(os.Args); err != nil {
+		panic(err)
+	}
 
+	v, err := newViper(flags)
+	if err != nil {
+		panic(fmt.Errorf("bind flags: %w", err))
+	}
+
+	switch {
+	case help != nil && *help:
+		fmt.Printf("FrostFS S3 gateway %s\n", version.Version)
+		flags.PrintDefaults()
+
+		fmt.Println()
+		fmt.Println("Default environments:")
+		fmt.Println()
+		keys := v.AllKeys()
+		sort.Strings(keys)
+
+		for i := range keys {
+			if _, ok := ignore[keys[i]]; ok {
+				continue
+			}
+
+			defaultValue := v.GetString(keys[i])
+			if len(defaultValue) == 0 {
+				continue
+			}
+
+			k := strings.Replace(keys[i], ".", "_", -1)
+			fmt.Printf("%s_%s = %s\n", envPrefix, strings.ToUpper(k), defaultValue)
+		}
+
+		fmt.Println()
+		fmt.Println("Peers preset:")
+		fmt.Println()
+
+		fmt.Printf("%s_%s_[N]_ADDRESS = string\n", envPrefix, strings.ToUpper(cfgPeers))
+		fmt.Printf("%s_%s_[N]_WEIGHT = 0..1 (float)\n", envPrefix, strings.ToUpper(cfgPeers))
+
+		os.Exit(0)
+	case versionFlag != nil && *versionFlag:
+		fmt.Printf("FrostFS S3 Gateway\nVersion: %s\nGoVersion: %s\n", version.Version, runtime.Version())
+		os.Exit(0)
+	}
+
+	if err = readInConfig(v); err != nil {
+		panic(err)
+	}
+
+	return &appCfg{
+		flags:    flags,
+		settings: v,
+	}
+}
+
+func setDefaults(v *viper.Viper, flags *pflag.FlagSet) {
 	v.SetDefault(cfgAccessBoxCacheRemovingCheckInterval, defaultAccessBoxCacheRemovingCheckInterval)
 
 	// logger:
@@ -909,78 +1019,21 @@ func newSettings() *viper.Viper {
 	// multinet
 	v.SetDefault(cfgMultinetFallbackDelay, defaultMultinetFallbackDelay)
 
-	// Bind flags
+	if resolveMethods, err := flags.GetStringSlice(cfgResolveOrder); err == nil {
-	if err := bindFlags(v, flags); err != nil {
+		v.SetDefault(cfgResolveOrder, resolveMethods)
-		panic(fmt.Errorf("bind flags: %w", err))
 	}
 
-	if err := flags.Parse(os.Args); err != nil {
+	if peers, err := flags.GetStringArray(cfgPeers); err == nil {
-		panic(err)
+		for i := range peers {
-	}
+			v.SetDefault(cfgPeers+"."+strconv.Itoa(i)+".address", peers[i])
-
-	if v.IsSet(cfgServer+".0."+cfgTLSKeyFile) && v.IsSet(cfgServer+".0."+cfgTLSCertFile) {
-		v.Set(cfgServer+".0."+cfgTLSEnabled, true)
-	}
-
-	if resolveMethods != nil {
-		v.SetDefault(cfgResolveOrder, *resolveMethods)
-	}
-
-	if peers != nil && len(*peers) > 0 {
-		for i := range *peers {
-			v.SetDefault(cfgPeers+"."+strconv.Itoa(i)+".address", (*peers)[i])
 			v.SetDefault(cfgPeers+"."+strconv.Itoa(i)+".weight", 1)
 			v.SetDefault(cfgPeers+"."+strconv.Itoa(i)+".priority", 1)
 		}
 	}
 
-	if domains != nil && len(*domains) > 0 {
+	if domains, err := flags.GetStringSlice(cfgListenDomains); err == nil && len(domains) > 0 {
-		v.SetDefault(cfgListenDomains, *domains)
+		v.SetDefault(cfgListenDomains, domains)
 	}
-
-	switch {
-	case help != nil && *help:
-		fmt.Printf("FrostFS S3 gateway %s\n", version.Version)
-		flags.PrintDefaults()
-
-		fmt.Println()
-		fmt.Println("Default environments:")
-		fmt.Println()
-		keys := v.AllKeys()
-		sort.Strings(keys)
-
-		for i := range keys {
-			if _, ok := ignore[keys[i]]; ok {
-				continue
-			}
-
-			defaultValue := v.GetString(keys[i])
-			if len(defaultValue) == 0 {
-				continue
-			}
-
-			k := strings.Replace(keys[i], ".", "_", -1)
-			fmt.Printf("%s_%s = %s\n", envPrefix, strings.ToUpper(k), defaultValue)
-		}
-
-		fmt.Println()
-		fmt.Println("Peers preset:")
-		fmt.Println()
-
-		fmt.Printf("%s_%s_[N]_ADDRESS = string\n", envPrefix, strings.ToUpper(cfgPeers))
-		fmt.Printf("%s_%s_[N]_WEIGHT = 0..1 (float)\n", envPrefix, strings.ToUpper(cfgPeers))
-
-		os.Exit(0)
-	case versionFlag != nil && *versionFlag:
-		fmt.Printf("FrostFS S3 Gateway\nVersion: %s\nGoVersion: %s\n", version.Version, runtime.Version())
-		os.Exit(0)
-	}
-
-	if err := readInConfig(v); err != nil {
-		panic(err)
-	}
-
-	return v
 }
 
 func bindFlags(v *viper.Viper, flags *pflag.FlagSet) error {

cmd/s3-gw/main.go

@@ -9,10 +9,10 @@ import (
 func main() {
 	g, _ := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
 
-	v := newSettings()
+	cfg := newSettings()
-	l := pickLogger(v)
+	l := pickLogger(cfg.config())
 
-	a := newApp(g, l, v)
+	a := newApp(g, l, cfg)
 
 	go a.Serve(g)