[#493] cmd/node: Add metrics section to config

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

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

@@ -0,0 +1,40 @@
+package metricsconfig
+
+import (
+	"time"
+
+	"github.com/nspcc-dev/neofs-node/cmd/neofs-node/config"
+)
+
+const (
+	subsection = "metrics"
+
+	ShutdownTimeoutDefault = 30 * time.Second
+	AddressDefault         = ""
+)
+
+// ShutdownTimeout returns value of "shutdown_timeout" config parameter
+// from "metrics" section.
+//
+// Returns ShutdownTimeoutDefault if value is not set.
+func ShutdownTimeout(c *config.Config) time.Duration {
+	v := config.DurationSafe(c.Sub(subsection), "shutdown_timeout")
+	if v != 0 {
+		return v
+	}
+
+	return ShutdownTimeoutDefault
+}
+
+// Address returns value of "address" config parameter
+// from "metrics" section.
+//
+// Returns AddressDefault if value is not set.
+func Address(c *config.Config) string {
+	v := config.StringSafe(c.Sub(subsection), "address")
+	if v != "" {
+		return v
+	}
+
+	return AddressDefault
+}