[#259] pkg/netmap: Implement v2-compatible NetworkInfo type

Define NetworkInfo structure. Implement constructors, fields getters and
setters, binary and JSON encoding methods.

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

pkg/netmap/network_info.go

@@ -0,0 +1,80 @@
+package netmap
+
+import (
+	"github.com/nspcc-dev/neofs-api-go/v2/netmap"
+)
+
+// NetworkInfo represents v2-compatible structure
+// with information about NeoFS network.
+type NetworkInfo netmap.NetworkInfo
+
+// NewNetworkInfoFromV2 wraps v2 NetworkInfo message to NetworkInfo.
+func NewNetworkInfoFromV2(iV2 *netmap.NetworkInfo) *NetworkInfo {
+	return (*NetworkInfo)(iV2)
+}
+
+// NewNetworkInfo creates and initializes blank NetworkInfo.
+func NewNetworkInfo() *NetworkInfo {
+	return NewNetworkInfoFromV2(new(netmap.NetworkInfo))
+}
+
+// ToV2 converts NetworkInfo to v2 NetworkInfo.
+func (i *NetworkInfo) ToV2() *netmap.NetworkInfo {
+	return (*netmap.NetworkInfo)(i)
+}
+
+// CurrentEpoch returns current epoch of the NeoFS network.
+func (i *NetworkInfo) CurrentEpoch() uint64 {
+	return (*netmap.NetworkInfo)(i).
+		GetCurrentEpoch()
+}
+
+// SetCurrentEpoch sets current epoch of the NeoFS network.
+func (i *NetworkInfo) SetCurrentEpoch(epoch uint64) {
+	(*netmap.NetworkInfo)(i).
+		SetCurrentEpoch(epoch)
+}
+
+// MagicNumber returns magic number of the sidechain.
+func (i *NetworkInfo) MagicNumber() uint64 {
+	return (*netmap.NetworkInfo)(i).
+		GetMagicNumber()
+}
+
+// SetMagicNumber sets magic number of the sidechain.
+func (i *NetworkInfo) SetMagicNumber(epoch uint64) {
+	(*netmap.NetworkInfo)(i).
+		SetMagicNumber(epoch)
+}
+
+// Marshal marshals NetworkInfo into a protobuf binary form.
+//
+// Buffer is allocated when the argument is empty.
+// Otherwise, the first buffer is used.
+func (i *NetworkInfo) Marshal(b ...[]byte) ([]byte, error) {
+	var buf []byte
+	if len(b) > 0 {
+		buf = b[0]
+	}
+
+	return (*netmap.NetworkInfo)(i).
+		StableMarshal(buf)
+}
+
+// Unmarshal unmarshals protobuf binary representation of NetworkInfo.
+func (i *NetworkInfo) Unmarshal(data []byte) error {
+	return (*netmap.NetworkInfo)(i).
+		Unmarshal(data)
+}
+
+// MarshalJSON encodes NetworkInfo to protobuf JSON format.
+func (i *NetworkInfo) MarshalJSON() ([]byte, error) {
+	return (*netmap.NetworkInfo)(i).
+		MarshalJSON()
+}
+
+// UnmarshalJSON decodes NetworkInfo from protobuf JSON format.
+func (i *NetworkInfo) UnmarshalJSON(data []byte) error {
+	return (*netmap.NetworkInfo)(i).
+		UnmarshalJSON(data)
+}

pkg/netmap/network_info_test.go

@@ -0,0 +1,53 @@
+package netmap
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestNetworkInfo_CurrentEpoch(t *testing.T) {
+	i := NewNetworkInfo()
+	e := uint64(13)
+
+	i.SetCurrentEpoch(e)
+
+	require.Equal(t, e, i.CurrentEpoch())
+	require.Equal(t, e, i.ToV2().GetCurrentEpoch())
+}
+
+func TestNetworkInfo_MagicNumber(t *testing.T) {
+	i := NewNetworkInfo()
+	m := uint64(666)
+
+	i.SetMagicNumber(m)
+
+	require.Equal(t, m, i.MagicNumber())
+	require.Equal(t, m, i.ToV2().GetMagicNumber())
+}
+
+func TestNetworkInfoEncoding(t *testing.T) {
+	i := NewNetworkInfo()
+	i.SetCurrentEpoch(13)
+	i.SetMagicNumber(666)
+
+	t.Run("binary", func(t *testing.T) {
+		data, err := i.Marshal()
+		require.NoError(t, err)
+
+		i2 := NewNetworkInfo()
+		require.NoError(t, i2.Unmarshal(data))
+
+		require.Equal(t, i, i2)
+	})
+
+	t.Run("json", func(t *testing.T) {
+		data, err := i.MarshalJSON()
+		require.NoError(t, err)
+
+		i2 := NewNetworkInfo()
+		require.NoError(t, i2.UnmarshalJSON(data))
+
+		require.Equal(t, i, i2)
+	})
+}