[#351] container: Add default value for NNS zone

Define `SysAttributeZoneDefault` constant for default zone in V2 code. Add
`SetNativeName` function which sets name with default zone.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

pkg/container/attribute.go

@@ -109,11 +109,18 @@ func iterateAttributes(c *Container, f func(*Attribute) bool) {
 }
 
 // SetNativeNameWithZone sets container native name and its zone.
+//
+// Use SetNativeName to set default zone.
 func SetNativeNameWithZone(c *Container, name, zone string) {
 	setAttribute(c, container.SysAttributeName, name)
 	setAttribute(c, container.SysAttributeZone, zone)
 }
 
+// SetNativeName sets container native name with default zone (container).
+func SetNativeName(c *Container, name string) {
+	SetNativeNameWithZone(c, name, container.SysAttributeZoneDefault)
+}
+
 // GetNativeNameWithZone returns container native name and its zone.
 func GetNativeNameWithZone(c *Container) (name string, zone string) {
 	iterateAttributes(c, func(a *Attribute) bool {

pkg/container/attribute_test.go

@@ -140,3 +140,16 @@ func TestGetNameWithZone(t *testing.T) {
 		require.Equal(t, item.zone, zone, item.zone)
 	}
 }
+
+func TestSetNativeName(t *testing.T) {
+	c := container.New()
+
+	const nameDefZone = "some name"
+
+	container.SetNativeName(c, nameDefZone)
+
+	name, zone := container.GetNativeNameWithZone(c)
+
+	require.Equal(t, nameDefZone, name)
+	require.Equal(t, containerv2.SysAttributeZoneDefault, zone)
+}

v2/container/attributes.go

@@ -13,3 +13,6 @@ const (
 	// SysAttributeZone is a string of zone for container name.
 	SysAttributeZone = SysAttributePrefix + "ZONE"
 )
+
+// SysAttributeZoneDefault is a default value for SysAttributeZone attribute.
+const SysAttributeZoneDefault = "container"