[#142] Fix multipart-objects download

Signed-off-by: Nikita Zinkevich <n.zinkevich@yadro.com>

internal/data/object.go

@@ -0,0 +1,41 @@
+package data
+
+import (
+	"time"
+
+	cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
+	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
+)
+
+type (
+	ObjectInfo struct {
+		ID  oid.ID
+		CID cid.ID
+
+		Bucket  string
+		Name    string
+		Size    uint64
+		Headers map[string]string
+	}
+
+	// PartInfo is upload information about part.
+	PartInfo struct {
+		Key      string    `json:"key"`
+		UploadID string    `json:"uploadId"`
+		Number   int       `json:"number"`
+		OID      oid.ID    `json:"oid"`
+		Size     uint64    `json:"size"`
+		ETag     string    `json:"etag"`
+		MD5      string    `json:"md5"`
+		Created  time.Time `json:"created"`
+	}
+)
+
+// Address returns object address.
+func (o *ObjectInfo) Address() oid.Address {
+	var addr oid.Address
+	addr.SetContainer(o.CID)
+	addr.SetObject(o.ID)
+
+	return addr
+}