[#702] Refactor app initialization

Signed-off-by: Denis Kirillov <denis@nspcc.ru>

cmd/s3-gw/app.go

@@ -39,20 +39,20 @@ type (
 		log  *zap.Logger
 		cfg  *viper.Viper
 		pool *pool.Pool
+		key  *keys.PrivateKey
+		nc   *notifications.Controller
 		obj  layer.Client
 		api  api.Handler
 
 		metrics        *appMetrics
 		bucketResolver *resolver.BucketResolver
 		tlsProvider    *certProvider
-
+		services       []*Service
-		maxClients api.MaxClients
+		settings       *appSettings
+		maxClients     api.MaxClients
 
 		webDone chan struct{}
 		wrkDone chan struct{}
-
-		services []*Service
-		settings *appSettings
 	}
 
 	appSettings struct {
@@ -87,159 +87,89 @@ type (
 )
 
 func newApp(ctx context.Context, log *Logger, v *viper.Viper) *App {
-	l := log.logger
+	conns, key := getPool(ctx, log.logger, v)
-
-	var (
-		key    *keys.PrivateKey
-		err    error
-		caller api.Handler
-		ctr    auth.Center
-		obj    layer.Client
-		nc     *notifications.Controller
-
-		prmPool pool.InitParameters
-
-		reBalance  = defaultRebalanceInterval
-		conTimeout = defaultConnectTimeout
-		hckTimeout = defaultHealthcheckTimeout
-
-		maxClientsCount    = defaultMaxClientsCount
-		maxClientsDeadline = defaultMaxClientsDeadline
-		poolErrorThreshold = defaultPoolErrorThreshold
-	)
-
-	if v := v.GetDuration(cfgConnectTimeout); v > 0 {
-		conTimeout = v
-	}
-
-	if v := v.GetDuration(cfgHealthcheckTimeout); v > 0 {
-		hckTimeout = v
-	}
-
-	if v := v.GetInt(cfgMaxClientsCount); v > 0 {
-		maxClientsCount = v
-	}
-
-	if v := v.GetDuration(cfgMaxClientsDeadline); v > 0 {
-		maxClientsDeadline = v
-	}
-
-	if v := v.GetDuration(cfgRebalanceInterval); v > 0 {
-		reBalance = v
-	}
-
-	if v := v.GetUint32(cfgPoolErrorThreshold); v > 0 {
-		poolErrorThreshold = v
-	}
-
-	password := wallet.GetPassword(v, cfgWalletPassphrase)
-	if key, err = wallet.GetKeyFromPath(v.GetString(cfgWalletPath), v.GetString(cfgWalletAddress), password); err != nil {
-		l.Fatal("could not load NeoFS private key", zap.Error(err))
-	}
-
-	l.Info("using credentials", zap.String("NeoFS", hex.EncodeToString(key.PublicKey().Bytes())))
-
-	prmPool.SetKey(&key.PrivateKey)
-	prmPool.SetNodeDialTimeout(conTimeout)
-	prmPool.SetHealthcheckTimeout(hckTimeout)
-	prmPool.SetErrorThreshold(poolErrorThreshold)
-	prmPool.SetClientRebalanceInterval(reBalance)
-	for _, peer := range fetchPeers(l, v) {
-		prmPool.AddNode(peer)
-	}
-
-	conns, err := pool.NewPool(prmPool)
-	if err != nil {
-		l.Fatal("failed to create connection pool", zap.Error(err))
-	}
-
-	if err = conns.Dial(ctx); err != nil {
-		l.Fatal("failed to dial connection pool", zap.Error(err))
-	}
-
-	// prepare random key for anonymous requests
-	randomKey, err := keys.NewPrivateKey()
-	if err != nil {
-		l.Fatal("couldn't generate random key", zap.Error(err))
-	}
-
-	resolveCfg := &resolver.Config{
-		NeoFS:      neofs.NewResolverNeoFS(conns),
-		RPCAddress: v.GetString(cfgRPCEndpoint),
-	}
-
-	order := v.GetStringSlice(cfgResolveOrder)
-	if resolveCfg.RPCAddress == "" {
-		order = remove(order, resolver.NNSResolver)
-		l.Warn(fmt.Sprintf("resolver '%s' won't be used since '%s' isn't provided", resolver.NNSResolver, cfgRPCEndpoint))
-	}
-
-	bucketResolver, err := resolver.NewBucketResolver(order, resolveCfg)
-	if err != nil {
-		l.Fatal("failed to form resolver", zap.Error(err))
-	}
-
-	treeServiceEndpoint := v.GetString(cfgTreeServiceEndpoint)
-	treeService, err := neofs.NewTreeClient(treeServiceEndpoint, key)
-	if err != nil {
-		l.Fatal("failed to create tree service", zap.Error(err))
-	}
-	l.Info("init tree service", zap.String("endpoint", treeServiceEndpoint))
-
-	layerCfg := &layer.Config{
-		Caches: getCacheOptions(v, l),
-		AnonKey: layer.AnonymousKey{
-			Key: randomKey,
-		},
-		Resolver:    bucketResolver,
-		TreeService: treeService,
-	}
-
-	// prepare object layer
-	obj = layer.NewLayer(l, neofs.NewNeoFS(conns), layerCfg)
-
-	if v.GetBool(cfgEnableNATS) {
-		nopts := getNotificationsOptions(v, l)
-		nc, err = notifications.NewController(nopts, l)
-		if err != nil {
-			l.Fatal("failed to enable notifications", zap.Error(err))
-		}
-
-		if err = obj.Initialize(ctx, nc); err != nil {
-			l.Fatal("couldn't initialize layer", zap.Error(err))
-		}
-	}
 
 	// prepare auth center
-	ctr = auth.New(neofs.NewAuthmateNeoFS(conns), key, v.GetStringSlice(cfgAllowedAccessKeyIDPrefixes), getAccessBoxCacheConfig(v, l))
+	ctr := auth.New(neofs.NewAuthmateNeoFS(conns), key, v.GetStringSlice(cfgAllowedAccessKeyIDPrefixes), getAccessBoxCacheConfig(v, log.logger))
-	handlerOptions := getHandlerOptions(v, l)
-
-	if caller, err = handler.New(l, obj, nc, handlerOptions); err != nil {
-		l.Fatal("could not initialize API handler", zap.Error(err))
-	}
 
 	app := &App{
 		ctr:  ctr,
-		log:  l,
+		log:  log.logger,
 		cfg:  v,
 		pool: conns,
-		obj:  obj,
+		key:  key,
-		api:  caller,
 
 		webDone: make(chan struct{}, 1),
 		wrkDone: make(chan struct{}, 1),
 
-		maxClients: api.NewMaxClientsMiddleware(maxClientsCount, maxClientsDeadline),
+		maxClients: newMaxClients(v),
 		settings:   &appSettings{LogLevel: log.lvl},
 	}
 
-	app.initMetrics()
+	app.init(ctx)
-	app.initResolver()
-	app.initTLSProvider()
 
 	return app
 }
 
+func (a *App) init(ctx context.Context) {
+	a.initHandlers(ctx)
+	a.initMetrics()
+	a.initTLSProvider()
+}
+
+func (a *App) initLayer(ctx context.Context) {
+	a.initResolver()
+
+	treeServiceEndpoint := a.cfg.GetString(cfgTreeServiceEndpoint)
+	treeService, err := neofs.NewTreeClient(treeServiceEndpoint, a.key)
+	if err != nil {
+		a.log.Fatal("failed to create tree service", zap.Error(err))
+	}
+	a.log.Info("init tree service", zap.String("endpoint", treeServiceEndpoint))
+
+	// prepare random key for anonymous requests
+	randomKey, err := keys.NewPrivateKey()
+	if err != nil {
+		a.log.Fatal("couldn't generate random key", zap.Error(err))
+	}
+
+	layerCfg := &layer.Config{
+		Caches: getCacheOptions(a.cfg, a.log),
+		AnonKey: layer.AnonymousKey{
+			Key: randomKey,
+		},
+		Resolver:    a.bucketResolver,
+		TreeService: treeService,
+	}
+
+	// prepare object layer
+	a.obj = layer.NewLayer(a.log, neofs.NewNeoFS(a.pool), layerCfg)
+
+	if a.cfg.GetBool(cfgEnableNATS) {
+		nopts := getNotificationsOptions(a.cfg, a.log)
+		a.nc, err = notifications.NewController(nopts, a.log)
+		if err != nil {
+			a.log.Fatal("failed to enable notifications", zap.Error(err))
+		}
+
+		if err = a.obj.Initialize(ctx, a.nc); err != nil {
+			a.log.Fatal("couldn't initialize layer", zap.Error(err))
+		}
+	}
+}
+
+func (a *App) initHandlers(ctx context.Context) {
+	a.initLayer(ctx)
+
+	var err error
+	handlerOptions := getHandlerOptions(a.cfg, a.log)
+
+	a.api, err = handler.New(a.log, a.obj, a.nc, handlerOptions)
+	if err != nil {
+		a.log.Fatal("could not initialize API handler", zap.Error(err))
+	}
+}
+
 func (a *App) initMetrics() {
 	gateMetricsProvider := newGateMetrics(neofs.NewPoolStatistic(a.pool))
 	a.metrics = newAppMetrics(a.log, gateMetricsProvider, a.cfg.GetBool(cfgPrometheusEnabled))
@@ -278,6 +208,72 @@ func (a *App) getResolverConfig() ([]string, *resolver.Config) {
 	return order, resolveCfg
 }
 
+func newMaxClients(cfg *viper.Viper) api.MaxClients {
+	maxClientsCount := cfg.GetInt(cfgMaxClientsCount)
+	if maxClientsCount <= 0 {
+		maxClientsCount = defaultMaxClientsCount
+	}
+
+	maxClientsDeadline := cfg.GetDuration(cfgMaxClientsDeadline)
+	if maxClientsDeadline <= 0 {
+		maxClientsDeadline = defaultMaxClientsDeadline
+	}
+
+	return api.NewMaxClientsMiddleware(maxClientsCount, maxClientsDeadline)
+}
+
+func getPool(ctx context.Context, logger *zap.Logger, cfg *viper.Viper) (*pool.Pool, *keys.PrivateKey) {
+	var prm pool.InitParameters
+
+	password := wallet.GetPassword(cfg, cfgWalletPassphrase)
+	key, err := wallet.GetKeyFromPath(cfg.GetString(cfgWalletPath), cfg.GetString(cfgWalletAddress), password)
+	if err != nil {
+		logger.Fatal("could not load NeoFS private key", zap.Error(err))
+	}
+
+	prm.SetKey(&key.PrivateKey)
+	logger.Info("using credentials", zap.String("NeoFS", hex.EncodeToString(key.PublicKey().Bytes())))
+
+	for _, peer := range fetchPeers(logger, cfg) {
+		prm.AddNode(peer)
+	}
+
+	connTimeout := cfg.GetDuration(cfgConnectTimeout)
+	if connTimeout <= 0 {
+		connTimeout = defaultConnectTimeout
+	}
+	prm.SetNodeDialTimeout(connTimeout)
+
+	healthCheckTimeout := cfg.GetDuration(cfgHealthcheckTimeout)
+	if healthCheckTimeout <= 0 {
+		healthCheckTimeout = defaultHealthcheckTimeout
+	}
+	prm.SetNodeDialTimeout(healthCheckTimeout)
+
+	rebalanceInterval := cfg.GetDuration(cfgRebalanceInterval)
+	if rebalanceInterval <= 0 {
+		rebalanceInterval = defaultRebalanceInterval
+	}
+	prm.SetClientRebalanceInterval(rebalanceInterval)
+
+	errorThreshold := cfg.GetUint32(cfgPoolErrorThreshold)
+	if errorThreshold <= 0 {
+		errorThreshold = defaultPoolErrorThreshold
+	}
+	prm.SetErrorThreshold(errorThreshold)
+
+	p, err := pool.NewPool(prm)
+	if err != nil {
+		logger.Fatal("failed to create connection pool", zap.Error(err))
+	}
+
+	if err = p.Dial(ctx); err != nil {
+		logger.Fatal("failed to dial connection pool", zap.Error(err))
+	}
+
+	return p, key
+}
+
 func newAppMetrics(logger *zap.Logger, provider GateMetricsCollector, enabled bool) *appMetrics {
 	if !enabled {
 		logger.Warn("metrics are disabled")