[#798] neofs-node/config: Add persistent_state section

Signed-off-by: Alex Vanin <alexey@nspcc.ru>

cmd/neofs-node/config/node/config.go

@@ -11,10 +11,20 @@ import (
 	utilConfig "github.com/nspcc-dev/neofs-node/pkg/util/config"
 )
 
+// PersistentStateConfig is a wrapper over "persistent_state" config section
+// which provides access to persistent state storage configuration of node.
+type PersistentStateConfig struct {
+	cfg *config.Config
+}
+
 const (
-	subsection = "node"
+	subsection                = "node"
+	persistentStateSubsection = "persistent_state"
 
 	attributePrefix = "attribute"
+
+	// PersistentStatePathDefault is a default path for persistent state file.
+	PersistentStatePathDefault = ".neofs-storage-state"
 )
 
 // Key returns value of "key" config parameter
@@ -115,3 +125,23 @@ func Attributes(c *config.Config) (attrs []string) {
 func Relay(c *config.Config) bool {
 	return config.BoolSafe(c.Sub(subsection), "relay")
 }
+
+// PersistentState returns structure that provides access to "persistent_state"
+// subsection of "node" section.
+func PersistentState(c *config.Config) PersistentStateConfig {
+	return PersistentStateConfig{
+		c.Sub(subsection).Sub(persistentStateSubsection),
+	}
+}
+
+// Path returns value of "path" config parameter.
+//
+// Returns PersistentStatePathDefault if value is not a non-empty string.
+func (p PersistentStateConfig) Path() string {
+	v := config.String(p.cfg, "path")
+	if v != "" {
+		return v
+	}
+
+	return PersistentStatePathDefault
+}

cmd/neofs-node/config/node/config_test.go

@@ -30,9 +30,11 @@ func TestNodeSection(t *testing.T) {
 
 		attribute := Attributes(empty)
 		relay := Relay(empty)
+		persistatePath := PersistentState(empty).Path()
 
 		require.Empty(t, attribute)
 		require.Equal(t, false, relay)
+		require.Equal(t, PersistentStatePathDefault, persistatePath)
 	})
 
 	const path = "../../../../config/example/node"
@@ -43,6 +45,7 @@ func TestNodeSection(t *testing.T) {
 		attributes := Attributes(c)
 		relay := Relay(c)
 		wKey := Wallet(c)
+		persistatePath := PersistentState(c).Path()
 
 		expectedAddr := []struct {
 			str  string
@@ -94,6 +97,8 @@ func TestNodeSection(t *testing.T) {
 		require.Equal(t,
 			config.StringSafe(c.Sub("node").Sub("wallet"), "address"),
 			address.Uint160ToString(wKey.GetScriptHash()))
+
+		require.Equal(t, "/state", persistatePath)
 	}
 
 	configtest.ForEachFileType(path, fileConfigTest)

config/example/node.env

@@ -15,6 +15,7 @@ NEOFS_NODE_ADDRESSES=s01.neofs.devenv:8080 /dns4/s02.neofs.devenv/tcp/8081 grpc:
 NEOFS_NODE_ATTRIBUTE_0=Price:11
 NEOFS_NODE_ATTRIBUTE_1=UN-LOCODE:RU MSK
 NEOFS_NODE_RELAY=true
+NEOFS_NODE_PERSISTENT_STATE_PATH=/state
 
 # gRPC section
 NEOFS_GRPC_NUM=2

config/example/node.json

@@ -25,7 +25,10 @@
     ],
     "attribute_0": "Price:11",
     "attribute_1": "UN-LOCODE:RU MSK",
-    "relay": true
+    "relay": true,
+    "persistent_state": {
+      "path": "/state"
+    }
   },
   "grpc": {
     "num": 2,

config/example/node.yaml

@@ -23,6 +23,8 @@ node:
   attribute_0: "Price:11"
   attribute_1: UN-LOCODE:RU MSK
   relay: true
+  persistent_state:
+    path: /state
 
 grpc:
   num: 2