[#142] Fix multipart-objects download

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

internal/handler/reader.go

@@ -47,20 +47,26 @@ func readContentType(maxSize uint64, rInit func(uint64) (io.Reader, error)) (str
 	return http.DetectContentType(buf), buf, err // to not lose io.EOF
 }
 
-func (h *Handler) receiveFile(ctx context.Context, req request, objectAddress oid.Address) {
+type getMultiobjectBodyParams struct {
+	obj     *Object
+	req     request
+	strSize string
+}
+
+func (h *Handler) receiveFile(ctx context.Context, req request, objAddress oid.Address) {
 	var (
-		err      error
-		dis      = "inline"
-		start    = time.Now()
-		filename string
-		filepath string
+		shouldDownload = req.QueryArgs().GetBool("download")
+		start          = time.Now()
+		filename       string
+		filepath       string
+		contentType    string
 	)
 
 	prm := PrmObjectGet{
 		PrmAuth: PrmAuth{
 			BearerToken: bearerToken(ctx),
 		},
-		Address: objectAddress,
+		Address: objAddress,
 	}
 
 	rObj, err := h.frostfs.GetObject(ctx, prm)
@@ -70,15 +76,9 @@ func (h *Handler) receiveFile(ctx context.Context, req request, objectAddress oi
 	}
 
 	// we can't close reader in this function, so how to do it?
-
-	if req.Request.URI().QueryArgs().GetBool("download") {
-		dis = "attachment"
-	}
-
+	req.setIDs(rObj.Header)
+	payload := rObj.Payload
 	payloadSize := rObj.Header.PayloadSize()
-
-	req.Response.Header.Set(fasthttp.HeaderContentLength, strconv.FormatUint(payloadSize, 10))
-	var contentType string
 	for _, attr := range rObj.Header.Attributes() {
 		key := attr.Key()
 		val := attr.Value()
@@ -93,31 +93,41 @@ func (h *Handler) receiveFile(ctx context.Context, req request, objectAddress oi
 		case object.AttributeFileName:
 			filename = val
 		case object.AttributeTimestamp:
-			value, err := strconv.ParseInt(val, 10, 64)
-			if err != nil {
-				req.log.Info(logs.CouldntParseCreationDate,
-					zap.String("key", key),
+			if err = req.setTimestamp(val); err != nil {
+				req.log.Error(logs.CouldntParseCreationDate,
 					zap.String("val", val),
 					zap.Error(err))
-				continue
 			}
-			req.Response.Header.Set(fasthttp.HeaderLastModified,
-				time.Unix(value, 0).UTC().Format(http.TimeFormat))
 		case object.AttributeContentType:
 			contentType = val
 		case object.AttributeFilePath:
 			filepath = val
+		case attributeMultipartObjectSize:
+			payload, payloadSize, err = h.getPayload(getMultiobjectBodyParams{
+				obj:     rObj,
+				req:     req,
+				strSize: val,
+			})
+			if err != nil {
+				req.handleFrostFSErr(err, start)
+				return
+			}
 		}
 	}
+	if filename == "" {
+		filename = filepath
+	}
 
-	idsToResponse(&req.Response, &rObj.Header)
+	req.setDisposition(shouldDownload, filename)
+
+	req.Response.Header.Set(fasthttp.HeaderContentLength, strconv.FormatUint(payloadSize, 10))
 
 	if len(contentType) == 0 {
 		// determine the Content-Type from the payload head
 		var payloadHead []byte
 
 		contentType, payloadHead, err = readContentType(payloadSize, func(uint64) (io.Reader, error) {
-			return rObj.Payload, nil
+			return payload, nil
 		})
 		if err != nil && err != io.EOF {
 			req.log.Error(logs.CouldNotDetectContentTypeFromPayload, zap.Error(err))
@@ -129,20 +139,46 @@ func (h *Handler) receiveFile(ctx context.Context, req request, objectAddress oi
 		var headReader io.Reader = bytes.NewReader(payloadHead)
 
 		if err != io.EOF { // otherwise, we've already read full payload
-			headReader = io.MultiReader(headReader, rObj.Payload)
+			headReader = io.MultiReader(headReader, payload)
 		}
 
 		// note: we could do with io.Reader, but SetBodyStream below closes body stream
 		// if it implements io.Closer and that's useful for us.
-		rObj.Payload = readCloser{headReader, rObj.Payload}
+		payload = readCloser{headReader, payload}
 	}
 	req.SetContentType(contentType)
+	req.Response.SetBodyStream(payload, int(payloadSize))
+}
 
-	if filename == "" {
-		filename = filepath
+func (r *request) setIDs(obj object.Object) {
+	objID, _ := obj.ID()
+	cnrID, _ := obj.ContainerID()
+	r.Response.Header.Set(hdrObjectID, objID.String())
+	r.Response.Header.Set(hdrOwnerID, obj.OwnerID().String())
+	r.Response.Header.Set(hdrContainerID, cnrID.String())
+}
+
+func (r *request) setDisposition(shouldDownload bool, filename string) {
+	const (
+		inlineDisposition     = "inline"
+		attachmentDisposition = "attachment"
+	)
+
+	dis := inlineDisposition
+	if shouldDownload {
+		dis = attachmentDisposition
 	}
 
-	req.Response.Header.Set(fasthttp.HeaderContentDisposition, dis+"; filename="+path.Base(filename))
-
-	req.Response.SetBodyStream(rObj.Payload, int(payloadSize))
+	r.Response.Header.Set(fasthttp.HeaderContentDisposition, dis+"; filename="+path.Base(filename))
+}
+
+func (r *request) setTimestamp(timestamp string) error {
+	value, err := strconv.ParseInt(timestamp, 10, 64)
+	if err != nil {
+		return err
+	}
+	r.Response.Header.Set(fasthttp.HeaderLastModified,
+		time.Unix(value, 0).UTC().Format(http.TimeFormat))
+
+	return nil
 }