[#132] sdk/object: Implement Address type

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

pkg/object/address.go

@@ -0,0 +1,68 @@
+package object
+
+import (
+	"github.com/nspcc-dev/neofs-api-go/pkg/container"
+	"github.com/nspcc-dev/neofs-api-go/v2/refs"
+	"github.com/pkg/errors"
+)
+
+// Address represents address of NeoFS object.
+type Address struct {
+	cid *container.ID
+
+	oid *ID
+}
+
+// ToV2 converts Address to v2 Address message.
+func (a *Address) ToV2() *refs.Address {
+	if a != nil {
+		aV2 := new(refs.Address)
+		aV2.SetContainerID(a.cid.ToV2())
+		aV2.SetObjectID(a.oid.ToV2())
+
+		return aV2
+	}
+
+	return nil
+}
+
+// GetObjectIDV2 converts object identifier to v2 ObjectID message.
+func (a *Address) GetObjectIDV2() *refs.ObjectID {
+	if a != nil {
+		return a.oid.ToV2()
+	}
+
+	return nil
+}
+
+// AddressFromV2 converts v2 Address message to Address.
+func AddressFromV2(aV2 *refs.Address) (*Address, error) {
+	if aV2 == nil {
+		return nil, nil
+	}
+
+	oid, err := IDFromV2(aV2.GetObjectID())
+	if err != nil {
+		return nil, errors.Wrap(err, "could not convert object identifier")
+	}
+
+	cid, err := container.IDFromV2(aV2.GetContainerID())
+	if err != nil {
+		return nil, errors.Wrap(err, "could not convert container identifier")
+	}
+
+	return &Address{
+		cid: cid,
+		oid: oid,
+	}, nil
+}
+
+// AddressFromBytes restores Address from a binary representation.
+func AddressFromBytes(data []byte) (*Address, error) {
+	addrV2 := new(refs.Address)
+	if err := addrV2.StableUnmarshal(data); err != nil {
+		return nil, errors.Wrap(err, "could not unmarshal object address")
+	}
+
+	return AddressFromV2(addrV2)
+}