[#266] Support per namespace placement policies configuration

Signed-off-by: Denis Kirillov <d.kirillov@yadro.com>

CHANGELOG.md

@@ -40,6 +40,7 @@ This document outlines major changes between releases.
 - Add new `logger.destination` config param (#236)
 - Add `X-Amz-Content-Sha256` header validation (#218)
 - Support frostfsid contract. See `frostfsid` config section (#260)
+- Support per namespace placement policies configuration (see `namespaces.config` config param) (#266)
 
 ### Changed
 - Update prometheus to v1.15.0 (#94)

api/handler/api.go

@@ -31,10 +31,10 @@ type (
 
 	// Config contains data which handler needs to keep.
 	Config interface {
-		DefaultPlacementPolicy() netmap.PlacementPolicy
+		DefaultPlacementPolicy(namespace string) netmap.PlacementPolicy
-		PlacementPolicy(string) (netmap.PlacementPolicy, bool)
+		PlacementPolicy(namespace, constraint string) (netmap.PlacementPolicy, bool)
-		CopiesNumbers(string) ([]uint32, bool)
+		CopiesNumbers(namespace, constraint string) ([]uint32, bool)
-		DefaultCopiesNumbers() []uint32
+		DefaultCopiesNumbers(namespace string) []uint32
 		NewXMLDecoder(io.Reader) *xml.Decoder
 		DefaultMaxAge() int
 		NotificatorEnabled() bool
@@ -74,7 +74,7 @@ func New(log *zap.Logger, obj layer.Client, notificator Notificator, cfg Config)
 // 1) array of copies numbers sent in request's header has the highest priority.
 // 2) array of copies numbers with corresponding location constraint provided in the config file.
 // 3) default copies number from the config file wrapped into array.
-func (h *handler) pickCopiesNumbers(metadata map[string]string, locationConstraint string) ([]uint32, error) {
+func (h *handler) pickCopiesNumbers(metadata map[string]string, namespace, locationConstraint string) ([]uint32, error) {
 	copiesNumbersStr, ok := metadata[layer.AttributeFrostfsCopiesNumber]
 	if ok {
 		result, err := parseCopiesNumbers(copiesNumbersStr)
@@ -84,12 +84,12 @@ func (h *handler) pickCopiesNumbers(metadata map[string]string, locationConstrai
 		return result, nil
 	}
 
-	copiesNumbers, ok := h.cfg.CopiesNumbers(locationConstraint)
+	copiesNumbers, ok := h.cfg.CopiesNumbers(namespace, locationConstraint)
 	if ok {
 		return copiesNumbers, nil
 	}
 
-	return h.cfg.DefaultCopiesNumbers(), nil
+	return h.cfg.DefaultCopiesNumbers(namespace), nil
 }
 
 func parseCopiesNumbers(copiesNumbersStr string) ([]uint32, error) {

api/handler/api_test.go

@@ -26,7 +26,7 @@ func TestCopiesNumberPicker(t *testing.T) {
 		metadata["somekey1"] = "5, 6, 7"
 		expectedCopiesNumbers := []uint32{1}
 
-		actualCopiesNumbers, err := h.pickCopiesNumbers(metadata, locationConstraint2)
+		actualCopiesNumbers, err := h.pickCopiesNumbers(metadata, "", locationConstraint2)
 		require.NoError(t, err)
 		require.Equal(t, expectedCopiesNumbers, actualCopiesNumbers)
 	})
@@ -35,7 +35,7 @@ func TestCopiesNumberPicker(t *testing.T) {
 		metadata["somekey2"] = "6, 7, 8"
 		expectedCopiesNumbers := []uint32{2, 3, 4}
 
-		actualCopiesNumbers, err := h.pickCopiesNumbers(metadata, locationConstraint1)
+		actualCopiesNumbers, err := h.pickCopiesNumbers(metadata, "", locationConstraint1)
 		require.NoError(t, err)
 		require.Equal(t, expectedCopiesNumbers, actualCopiesNumbers)
 	})
@@ -44,7 +44,7 @@ func TestCopiesNumberPicker(t *testing.T) {
 		metadata["frostfs-copies-number"] = "7, 8, 9"
 		expectedCopiesNumbers := []uint32{7, 8, 9}
 
-		actualCopiesNumbers, err := h.pickCopiesNumbers(metadata, locationConstraint2)
+		actualCopiesNumbers, err := h.pickCopiesNumbers(metadata, "", locationConstraint2)
 		require.NoError(t, err)
 		require.Equal(t, expectedCopiesNumbers, actualCopiesNumbers)
 	})
@@ -53,7 +53,7 @@ func TestCopiesNumberPicker(t *testing.T) {
 		metadata["frostfs-copies-number"] = "7,8,9"
 		expectedCopiesNumbers := []uint32{7, 8, 9}
 
-		actualCopiesNumbers, err := h.pickCopiesNumbers(metadata, locationConstraint2)
+		actualCopiesNumbers, err := h.pickCopiesNumbers(metadata, "", locationConstraint2)
 		require.NoError(t, err)
 		require.Equal(t, expectedCopiesNumbers, actualCopiesNumbers)
 	})
@@ -62,7 +62,7 @@ func TestCopiesNumberPicker(t *testing.T) {
 		metadata["frostfs-copies-number"] = "11, 12, 13, "
 		expectedCopiesNumbers := []uint32{11, 12, 13}
 
-		actualCopiesNumbers, err := h.pickCopiesNumbers(metadata, locationConstraint2)
+		actualCopiesNumbers, err := h.pickCopiesNumbers(metadata, "", locationConstraint2)
 		require.NoError(t, err)
 		require.Equal(t, expectedCopiesNumbers, actualCopiesNumbers)
 	})

api/handler/copy.go

@@ -204,7 +204,7 @@ func (h *handler) CopyObjectHandler(w http.ResponseWriter, r *http.Request) {
 		DstEncryption: dstEncryptionParams,
 	}
 
-	params.CopiesNumbers, err = h.pickCopiesNumbers(metadata, dstBktInfo.LocationConstraint)
+	params.CopiesNumbers, err = h.pickCopiesNumbers(metadata, reqInfo.Namespace, dstBktInfo.LocationConstraint)
 	if err != nil {
 		h.logAndSendError(w, "invalid copies number", reqInfo, err)
 		return

api/handler/cors.go

@@ -55,7 +55,7 @@ func (h *handler) PutBucketCorsHandler(w http.ResponseWriter, r *http.Request) {
 		NewDecoder: h.cfg.NewXMLDecoder,
 	}
 
-	p.CopiesNumbers, err = h.pickCopiesNumbers(parseMetadata(r), bktInfo.LocationConstraint)
+	p.CopiesNumbers, err = h.pickCopiesNumbers(parseMetadata(r), reqInfo.Namespace, bktInfo.LocationConstraint)
 	if err != nil {
 		h.logAndSendError(w, "invalid copies number", reqInfo, err)
 		return

api/handler/handlers_test.go

@@ -67,20 +67,20 @@ type configMock struct {
 	md5Enabled                    bool
 }
 
-func (c *configMock) DefaultPlacementPolicy() netmap.PlacementPolicy {
+func (c *configMock) DefaultPlacementPolicy(_ string) netmap.PlacementPolicy {
 	return c.defaultPolicy
 }
 
-func (c *configMock) PlacementPolicy(string) (netmap.PlacementPolicy, bool) {
+func (c *configMock) PlacementPolicy(_, _ string) (netmap.PlacementPolicy, bool) {
 	return netmap.PlacementPolicy{}, false
 }
 
-func (c *configMock) CopiesNumbers(locationConstraint string) ([]uint32, bool) {
+func (c *configMock) CopiesNumbers(_, locationConstraint string) ([]uint32, bool) {
 	result, ok := c.copiesNumbers[locationConstraint]
 	return result, ok
 }
 
-func (c *configMock) DefaultCopiesNumbers() []uint32 {
+func (c *configMock) DefaultCopiesNumbers(_ string) []uint32 {
 	return c.defaultCopiesNumbers
 }
 

api/handler/locking.go

@@ -145,7 +145,7 @@ func (h *handler) PutObjectLegalHoldHandler(w http.ResponseWriter, r *http.Reque
 		},
 	}
 
-	p.CopiesNumbers, err = h.pickCopiesNumbers(parseMetadata(r), bktInfo.LocationConstraint)
+	p.CopiesNumbers, err = h.pickCopiesNumbers(parseMetadata(r), reqInfo.Namespace, bktInfo.LocationConstraint)
 	if err != nil {
 		h.logAndSendError(w, "invalid copies number", reqInfo, err)
 		return
@@ -229,7 +229,7 @@ func (h *handler) PutObjectRetentionHandler(w http.ResponseWriter, r *http.Reque
 		NewLock: lock,
 	}
 
-	p.CopiesNumbers, err = h.pickCopiesNumbers(parseMetadata(r), bktInfo.LocationConstraint)
+	p.CopiesNumbers, err = h.pickCopiesNumbers(parseMetadata(r), reqInfo.Namespace, bktInfo.LocationConstraint)
 	if err != nil {
 		h.logAndSendError(w, "invalid copies number", reqInfo, err)
 		return

api/handler/multipart_upload.go

@@ -157,7 +157,7 @@ func (h *handler) CreateMultipartUploadHandler(w http.ResponseWriter, r *http.Re
 		p.Header[api.ContentLanguage] = contentLanguage
 	}
 
-	p.CopiesNumbers, err = h.pickCopiesNumbers(p.Header, bktInfo.LocationConstraint)
+	p.CopiesNumbers, err = h.pickCopiesNumbers(p.Header, reqInfo.Namespace, bktInfo.LocationConstraint)
 	if err != nil {
 		h.logAndSendError(w, "invalid copies number", reqInfo, err, additional...)
 		return

api/handler/notifications.go

@@ -115,7 +115,7 @@ func (h *handler) PutBucketNotificationHandler(w http.ResponseWriter, r *http.Re
 		Configuration: conf,
 	}
 
-	p.CopiesNumbers, err = h.pickCopiesNumbers(parseMetadata(r), bktInfo.LocationConstraint)
+	p.CopiesNumbers, err = h.pickCopiesNumbers(parseMetadata(r), reqInfo.Namespace, bktInfo.LocationConstraint)
 	if err != nil {
 		h.logAndSendError(w, "invalid copies number", reqInfo, err)
 		return

api/handler/put.go

@@ -248,7 +248,7 @@ func (h *handler) PutObjectHandler(w http.ResponseWriter, r *http.Request) {
 		ContentSHA256Hash: r.Header.Get(api.AmzContentSha256),
 	}
 
-	params.CopiesNumbers, err = h.pickCopiesNumbers(metadata, bktInfo.LocationConstraint)
+	params.CopiesNumbers, err = h.pickCopiesNumbers(metadata, reqInfo.Namespace, bktInfo.LocationConstraint)
 	if err != nil {
 		h.logAndSendError(w, "invalid copies number", reqInfo, err)
 		return
@@ -800,7 +800,7 @@ func (h *handler) CreateBucketHandler(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if err = h.setPolicy(p, createParams.LocationConstraint, policies); err != nil {
+	if err = h.setPolicy(p, reqInfo.Namespace, createParams.LocationConstraint, policies); err != nil {
 		h.logAndSendError(w, "couldn't set placement policy", reqInfo, err)
 		return
 	}
@@ -830,8 +830,8 @@ func (h *handler) CreateBucketHandler(w http.ResponseWriter, r *http.Request) {
 	middleware.WriteSuccessResponseHeadersOnly(w)
 }
 
-func (h handler) setPolicy(prm *layer.CreateBucketParams, locationConstraint string, userPolicies []*accessbox.ContainerPolicy) error {
+func (h handler) setPolicy(prm *layer.CreateBucketParams, namespace, locationConstraint string, userPolicies []*accessbox.ContainerPolicy) error {
-	prm.Policy = h.cfg.DefaultPlacementPolicy()
+	prm.Policy = h.cfg.DefaultPlacementPolicy(namespace)
 	prm.LocationConstraint = locationConstraint
 
 	if locationConstraint == "" {
@@ -845,7 +845,7 @@ func (h handler) setPolicy(prm *layer.CreateBucketParams, locationConstraint str
 		}
 	}
 
-	if policy, ok := h.cfg.PlacementPolicy(locationConstraint); ok {
+	if policy, ok := h.cfg.PlacementPolicy(namespace, locationConstraint); ok {
 		prm.Policy = policy
 		return nil
 	}

cmd/s3-gw/app.go

@@ -83,10 +83,7 @@ type (
 		isResolveListAllow bool // True if ResolveZoneList contains allowed zones
 
 		mu                            sync.RWMutex
-		defaultPolicy                 netmap.PlacementPolicy
+		namespaces                    Namespaces
-		regionMap                     map[string]netmap.PlacementPolicy
-		copiesNumbers                 map[string][]uint32
-		defaultCopiesNumbers          []uint32
 		defaultXMLNS                  bool
 		bypassContentEncodingInChunks bool
 		clientCut                     bool
@@ -187,6 +184,8 @@ func newAppSettings(log *Logger, v *viper.Viper) *appSettings {
 		defaultXMLNS:       v.GetBool(cfgKludgeUseDefaultXMLNS),
 		defaultMaxAge:      fetchDefaultMaxAge(v, log.logger),
 		notificatorEnabled: v.GetBool(cfgEnableNATS),
+		defaultNamespaces:  fetchDefaultNamespaces(log.logger, v),
+		namespaceHeader:    v.GetString(cfgResolveNamespaceHeader),
 	}
 
 	settings.resolveZoneList = v.GetStringSlice(cfgResolveBucketAllow)
@@ -200,8 +199,6 @@ func newAppSettings(log *Logger, v *viper.Viper) *appSettings {
 	settings.initPlacementPolicy(log.logger, v)
 	settings.setBufferMaxSizeForPut(v.GetUint64(cfgBufferMaxSizeForPut))
 	settings.setMD5Enabled(v.GetBool(cfgMD5Enabled))
-	settings.setNamespaceHeader(v.GetString(cfgResolveNamespaceHeader))
-	settings.setDefaultNamespaces(v.GetStringSlice(cfgKludgeDefaultNamespaces))
 
 	return settings
 }
@@ -243,46 +240,40 @@ func (s *appSettings) setBufferMaxSizeForPut(size uint64) {
 }
 
 func (s *appSettings) initPlacementPolicy(l *zap.Logger, v *viper.Viper) {
-	defaultPolicy := fetchDefaultPolicy(l, v)
+	nsConfig := fetchNamespacesConfig(l, v)
-	regionMap := fetchRegionMappingPolicies(l, v)
-	defaultCopies := fetchDefaultCopiesNumbers(l, v)
-	copiesNumbers := fetchCopiesNumbers(l, v)
 
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
-	s.defaultPolicy = defaultPolicy
+	s.namespaces = nsConfig.Namespaces
-	s.regionMap = regionMap
-	s.defaultCopiesNumbers = defaultCopies
-	s.copiesNumbers = copiesNumbers
 }
 
-func (s *appSettings) DefaultPlacementPolicy() netmap.PlacementPolicy {
+func (s *appSettings) DefaultPlacementPolicy(namespace string) netmap.PlacementPolicy {
 	s.mu.RLock()
 	defer s.mu.RUnlock()
-	return s.defaultPolicy
+	return s.namespaces[namespace].LocationConstraints[defaultConstraintName]
 }
 
-func (s *appSettings) PlacementPolicy(name string) (netmap.PlacementPolicy, bool) {
+func (s *appSettings) PlacementPolicy(namespace, constraint string) (netmap.PlacementPolicy, bool) {
 	s.mu.RLock()
-	policy, ok := s.regionMap[name]
+	policy, ok := s.namespaces[namespace].LocationConstraints[constraint]
 	s.mu.RUnlock()
 
 	return policy, ok
 }
 
-func (s *appSettings) CopiesNumbers(locationConstraint string) ([]uint32, bool) {
+func (s *appSettings) CopiesNumbers(namespace, constraint string) ([]uint32, bool) {
 	s.mu.RLock()
-	copiesNumbers, ok := s.copiesNumbers[locationConstraint]
+	copiesNumbers, ok := s.namespaces[namespace].CopiesNumbers[constraint]
 	s.mu.RUnlock()
 
 	return copiesNumbers, ok
 }
 
-func (s *appSettings) DefaultCopiesNumbers() []uint32 {
+func (s *appSettings) DefaultCopiesNumbers(namespace string) []uint32 {
 	s.mu.RLock()
 	defer s.mu.RUnlock()
-	return s.defaultCopiesNumbers
+	return s.namespaces[namespace].CopiesNumbers[defaultConstraintName]
 }
 
 func (s *appSettings) NewXMLDecoder(r io.Reader) *xml.Decoder {
@@ -687,6 +678,7 @@ func (a *App) updateSettings() {
 		a.settings.logLevel.SetLevel(lvl)
 	}
 
+	a.settings.setNamespaceHeader(a.cfg.GetString(cfgResolveNamespaceHeader)) // should be updated before placement policies
 	a.settings.initPlacementPolicy(a.log, a.cfg)
 
 	a.settings.useDefaultXMLNamespace(a.cfg.GetBool(cfgKludgeUseDefaultXMLNS))
@@ -694,7 +686,6 @@ func (a *App) updateSettings() {
 	a.settings.setClientCut(a.cfg.GetBool(cfgClientCut))
 	a.settings.setBufferMaxSizeForPut(a.cfg.GetUint64(cfgBufferMaxSizeForPut))
 	a.settings.setMD5Enabled(a.cfg.GetBool(cfgMD5Enabled))
-	a.settings.setNamespaceHeader(a.cfg.GetString(cfgResolveNamespaceHeader))
 	a.settings.setDefaultNamespaces(a.cfg.GetStringSlice(cfgKludgeDefaultNamespaces))
 }
 

cmd/s3-gw/app_settings.go

@@ -52,9 +52,14 @@ const (
 	defaultIdleTimeout       = 30 * time.Second
 
 	defaultNamespaceHeader = "X-Frostfs-Namespace"
+
+	defaultConstraintName = "default"
 )
 
-var defaultCopiesNumbers = []uint32{0}
+var (
+	defaultCopiesNumbers     = []uint32{0}
+	defaultDefaultNamespaces = []string{"", "root"}
+)
 
 const ( // Settings.
 	// Logger.
@@ -153,6 +158,9 @@ const ( // Settings.
 	cfgWebWriteTimeout      = "web.write_timeout"
 	cfgWebIdleTimeout       = "web.idle_timeout"
 
+	// Namespaces.
+	cfgNamespacesConfig = "namespaces.config"
+
 	// Command line args.
 	cmdHelp      = "help"
 	cmdVersion   = "version"
@@ -450,6 +458,81 @@ func fetchCopiesNumbers(l *zap.Logger, v *viper.Viper) map[string][]uint32 {
 	return copiesNums
 }
 
+func fetchDefaultNamespaces(l *zap.Logger, v *viper.Viper) []string {
+	defaultNamespaces := v.GetStringSlice(cfgKludgeDefaultNamespaces)
+	if len(defaultNamespaces) == 0 {
+		defaultNamespaces = defaultDefaultNamespaces
+		l.Warn(logs.DefaultNamespacesCannotBeEmpty, zap.Strings("namespaces", defaultNamespaces))
+	}
+
+	return defaultNamespaces
+}
+
+func fetchNamespacesConfig(l *zap.Logger, v *viper.Viper) NamespacesConfig {
+	defaultNSRegionMap := fetchRegionMappingPolicies(l, v)
+	defaultNSRegionMap[defaultConstraintName] = fetchDefaultPolicy(l, v)
+
+	defaultNSCopiesNumbers := fetchCopiesNumbers(l, v)
+	defaultNSCopiesNumbers[defaultConstraintName] = fetchDefaultCopiesNumbers(l, v)
+
+	defaultNSValue := Namespace{
+		LocationConstraints: defaultNSRegionMap,
+		CopiesNumbers:       defaultNSCopiesNumbers,
+	}
+
+	nsConfig, err := readNamespacesConfig(v.GetString(cfgNamespacesConfig))
+	if err != nil {
+		l.Warn(logs.FailedToParseNamespacesConfig)
+	}
+
+	defaultNamespacesNames := fetchDefaultNamespaces(l, v)
+
+	var overrideDefaults []Namespace
+	for _, name := range defaultNamespacesNames {
+		if ns, ok := nsConfig.Namespaces[name]; ok {
+			overrideDefaults = append(overrideDefaults, ns)
+			delete(nsConfig.Namespaces, name)
+		}
+	}
+
+	if len(overrideDefaults) > 0 {
+		l.Warn(logs.DefaultNamespaceConfigValuesBeOverwritten)
+		defaultNSValue.LocationConstraints = overrideDefaults[0].LocationConstraints
+		defaultNSValue.CopiesNumbers = overrideDefaults[0].CopiesNumbers
+		if len(overrideDefaults) > 1 {
+			l.Warn(logs.MultipleDefaultOverridesFound, zap.String("name", overrideDefaults[0].Name))
+		}
+	}
+
+	for _, name := range defaultNamespacesNames {
+		nsConfig.Namespaces[name] = Namespace{
+			Name:                name,
+			LocationConstraints: defaultNSValue.LocationConstraints,
+			CopiesNumbers:       defaultNSValue.CopiesNumbers,
+		}
+	}
+
+	return nsConfig
+}
+
+func readNamespacesConfig(filepath string) (NamespacesConfig, error) {
+	if filepath == "" {
+		return NamespacesConfig{}, nil
+	}
+
+	data, err := os.ReadFile(filepath)
+	if err != nil {
+		return NamespacesConfig{}, fmt.Errorf("failed to read namespace config '%s': %w", filepath, err)
+	}
+
+	var nsConfig NamespacesConfig
+	if err = json.Unmarshal(data, &nsConfig); err != nil {
+		return NamespacesConfig{}, fmt.Errorf("failed to parse namespace config: %w", err)
+	}
+
+	return nsConfig, nil
+}
+
 func fetchPeers(l *zap.Logger, v *viper.Viper) []pool.NodeParam {
 	var nodes []pool.NodeParam
 	for i := 0; ; i++ {
@@ -564,7 +647,7 @@ func newSettings() *viper.Viper {
 	// kludge
 	v.SetDefault(cfgKludgeUseDefaultXMLNS, false)
 	v.SetDefault(cfgKludgeBypassContentEncodingCheckInChunks, false)
-	v.SetDefault(cfgKludgeDefaultNamespaces, []string{"", "root"})
+	v.SetDefault(cfgKludgeDefaultNamespaces, defaultDefaultNamespaces)
 
 	// web
 	v.SetDefault(cfgWebReadHeaderTimeout, defaultReadHeaderTimeout)

cmd/s3-gw/decoder_test.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"bytes"
+	"encoding/json"
 	"testing"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/handler"
@@ -93,3 +94,53 @@ func TestDefaultNamespace(t *testing.T) {
 		})
 	}
 }
+
+func TestNamespacesMarshaling(t *testing.T) {
+	dataJSON := `
+{
+  "namespaces": {
+    "kapusta": {
+      "location_constraints": {
+        "default": "REP 3",
+        "load-1-1": "REP 1 CBF 1 SELECT 1 FROM *"
+      },
+      "copies_numbers": {
+        "default": [
+          0
+        ],
+        "load-1-1": [
+          1
+        ]
+      }
+    },
+    "root": {
+      "location_constraints": {
+        "default": "REP 3",
+        "test": "{\"replicas\":[{\"count\":1,\"selector\":\"\"}],\"containerBackupFactor\":1,\"selectors\":[{\"name\":\"\",\"count\":1,\"clause\":\"CLAUSE_UNSPECIFIED\",\"attribute\":\"\",\"filter\":\"Color\"}],\"filters\":[{\"name\":\"Color\",\"key\":\"Color\",\"op\":\"EQ\",\"value\":\"Red\",\"filters\":[]}],\"unique\":false}"
+      },
+      "copies_numbers": {
+        "default": [
+          0
+        ],
+        "load-1-1": [
+          1
+        ]
+      }
+    }
+  }
+}
+`
+
+	var nsConfig NamespacesConfig
+	err := json.Unmarshal([]byte(dataJSON), &nsConfig)
+	require.NoError(t, err)
+
+	data, err := json.Marshal(nsConfig)
+	require.NoError(t, err)
+
+	var nsConfig2 NamespacesConfig
+	err = json.Unmarshal(data, &nsConfig2)
+	require.NoError(t, err)
+
+	require.Equal(t, nsConfig, nsConfig2)
+}

cmd/s3-gw/namespaces.go

@@ -0,0 +1,79 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/netmap"
+)
+
+type NamespacesConfig struct {
+	Namespaces Namespaces `json:"namespaces"`
+}
+
+type Namespaces map[string]Namespace
+
+type Namespace struct {
+	Name                string              `json:"-"`
+	LocationConstraints LocationConstraints `json:"location_constraints"`
+	CopiesNumbers       map[string][]uint32 `json:"copies_numbers"`
+}
+
+type LocationConstraints map[string]netmap.PlacementPolicy
+
+func (c *Namespaces) UnmarshalJSON(data []byte) error {
+	namespaces := make(map[string]Namespace)
+	if err := json.Unmarshal(data, &namespaces); err != nil {
+		return err
+	}
+
+	for name, namespace := range namespaces {
+		namespace.Name = name
+		namespaces[name] = namespace
+	}
+
+	*c = namespaces
+
+	return nil
+}
+
+func (c *LocationConstraints) UnmarshalJSON(data []byte) error {
+	m := make(map[string]string)
+	if err := json.Unmarshal(data, &m); err != nil {
+		return err
+	}
+
+	*c = make(LocationConstraints, len(m))
+	for region, policy := range m {
+		var pp netmap.PlacementPolicy
+		if err := pp.DecodeString(policy); err == nil {
+			(*c)[region] = pp
+			continue
+		}
+
+		if err := pp.UnmarshalJSON([]byte(policy)); err == nil {
+			(*c)[region] = pp
+			continue
+		}
+
+		return fmt.Errorf("failed to parse location contraint '%s': '%s'", region, policy)
+	}
+
+	return nil
+}
+
+func (c LocationConstraints) MarshalJSON() ([]byte, error) {
+	m := make(map[string]string, len(c))
+
+	for region, policy := range c {
+		var sb strings.Builder
+		if err := policy.WriteStringTo(&sb); err != nil {
+			return nil, err
+		}
+
+		m[region] = sb.String()
+	}
+
+	return json.Marshal(m)
+}

config/config.env

@@ -183,3 +183,7 @@ S3_GW_WEB_IDLE_TIMEOUT=30s
 S3_GW_FROSTFSID_ENABLED=true
 # FrostfsID contract hash (LE) or name in NNS.
 S3_GW_FROSTFSID_CONTRACT=frostfsid.frostfs
+
+# Namespaces configuration
+S3_GW_NAMESPACES_CONFIG=namespaces.json
+

config/config.yaml

@@ -216,3 +216,6 @@ frostfsid:
   enabled: true
   # FrostfsID contract hash (LE) or name in NNS.
   contract: frostfsid.frostfs
+
+namespaces:
+  config: namespaces.json

docs/configuration.md

@@ -189,6 +189,7 @@ There are some custom types used for brevity:
 | `features`         | [Features configuration](#features-section)                    |
 | `web`              | [Web server configuration](#web-section)                       |
 | `frostfsid`        | [FrostfsID configuration](#frostfsid-section)                  |
+| `namespaces`       | [Namespaces configuration](#namespaces-section)                |
 
 ### General section
 
@@ -615,3 +616,41 @@ frostfsid:
 |------------|----------|---------------|-------------------|----------------------------------------------------------------------------------------|
 | `enabled`  | `bool`   | no            | true              | Enables check that allow requests only users that is registered in FrostfsID contract. |
 | `contract` | `string` | no            | frostfsid.frostfs | FrostfsID contract hash (LE) or name in NNS.                                           |
+
+# `namespaces` section
+
+Namespaces configuration.
+
+```yaml
+namespaces:
+  config: namespace.json
+```
+
+| Parameter | Type     | SIGHUP reload | Default value | Description                                         |
+|-----------|----------|---------------|---------------|-----------------------------------------------------|
+| `config`  | `string` | yes           |               | Path to json file with config value for namespaces. |
+
+## `namespaces.config` subsection 
+
+Example of `namespaces.json`.
+Note that config values from `namespaces.json` can override config values for default namespaces 
+(value for which are fetched from regular config value e.g. [placement-policy](#placement_policy-section)).
+To override config values for default namespaces use namespace names that are provided in `kludge.default_namespaces`.
+
+```json
+{
+  "namespaces": {
+    "namespace1": {
+      "location_constraints": {
+        "default": "REP 3", 
+        "test": "{\"replicas\":[{\"count\":1,\"selector\":\"\"}],\"containerBackupFactor\":0,\"selectors\":[],\"filters\":[],\"unique\":false}"
+      },
+      "copies_numbers": {
+        "default": [ 0 ],
+        "test": [ 1 ]
+      }
+    }
+  }
+}
+```
+

internal/logs/logs.go

@@ -40,6 +40,10 @@ const (
 	FailedToParseLocationConstraint                      = "failed to parse location constraint, it cannot be used"                                            // Warn in cmd/s3-gw/app_settings.go
 	FailedToParseDefaultCopiesNumbers                    = "failed to parse 'default' copies numbers, default one will be used"                                // Warn in cmd/s3-gw/app_settings.go
 	FailedToParseCopiesNumbers                           = "failed to parse copies numbers, skip"                                                              // Warn in cmd/s3-gw/app_settings.go
+	DefaultNamespacesCannotBeEmpty                       = "default namespaces cannot be empty, defaults will be used"                                         // Warn in cmd/s3-gw/app_settings.go
+	FailedToParseNamespacesConfig                        = "failed to unmarshal namespaces config"                                                             // Warn in cmd/s3-gw/app_settings.go
+	DefaultNamespaceConfigValuesBeOverwritten            = "default namespace config value be overwritten by values from 'namespaces.config'"                  // Warn in cmd/s3-gw/app_settings.go
+	MultipleDefaultOverridesFound                        = "multiple default overrides found, only one will be used"                                           // Warn in cmd/s3-gw/app_settings.go
 	FailedToParseDefaultDefaultLocationConstraint        = "failed to parse default 'default' location constraint"                                             // Fatal in cmd/s3-gw/app_settings.go
 	ConstraintAdded                                      = "constraint added"                                                                                  // Info in ../../cmd/s3-gw/app_settings.go
 	SkipEmptyAddress                                     = "skip, empty address"                                                                               // Warn in ../../cmd/s3-gw/app_settings.go