[#146] Move getting chunk payload reader to separate function

Signed-off-by: Denis Kirillov <d.kirillov@yadro.com>

api/handler/multipart_upload.go

@@ -217,6 +217,12 @@ func (h *handler) UploadPartHandler(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	body, err := h.getBodyReader(r)
+	if err != nil {
+		h.logAndSendError(w, "failed to get body reader", reqInfo, err)
+		return
+	}
+
 	var size uint64
 	if r.ContentLength > 0 {
 		size = uint64(r.ContentLength)
@@ -230,28 +236,7 @@ func (h *handler) UploadPartHandler(w http.ResponseWriter, r *http.Request) {
 		},
 		PartNumber: partNumber,
 		Size:       size,
-		Reader:     r.Body,
+		Reader:     body,
-	}
-
-	if api.IsSignedStreamingV4(r) {
-		if decodeContentSize := r.Header.Get(api.AmzDecodedContentLength); len(decodeContentSize) > 0 {
-			_, err := strconv.Atoi(decodeContentSize)
-			if err != nil {
-				h.logAndSendError(w, "cannot parse decode content length information", reqInfo,
-					errors.GetAPIError(errors.ErrMissingContentLength))
-				return
-			}
-		} else {
-			h.logAndSendError(w, "expecting decode content length information", reqInfo,
-				errors.GetAPIError(errors.ErrMissingContentLength))
-			return
-		}
-		chunkReader, err := newSignV4ChunkedReader(r)
-		if err != nil {
-			h.logAndSendError(w, "cannot initialize chunk reader", reqInfo, err)
-			return
-		}
-		p.Reader = chunkReader
 	}
 
 	p.Info.Encryption, err = formEncryptionParams(r)

api/handler/put.go

@@ -220,6 +220,12 @@ func (h *handler) PutObjectHandler(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	body, err := h.getBodyReader(r)
+	if err != nil {
+		h.logAndSendError(w, "failed to get body reader", reqInfo, err)
+		return
+	}
+
 	var size uint64
 	if r.ContentLength > 0 {
 		size = uint64(r.ContentLength)
@@ -228,33 +234,12 @@ func (h *handler) PutObjectHandler(w http.ResponseWriter, r *http.Request) {
 	params := &layer.PutObjectParams{
 		BktInfo:    bktInfo,
 		Object:     reqInfo.ObjectName,
-		Reader:     r.Body,
+		Reader:     body,
 		Size:       size,
 		Header:     metadata,
 		Encryption: encryptionParams,
 	}
 
-	if api.IsSignedStreamingV4(r) {
-		if decodeContentSize := r.Header.Get(api.AmzDecodedContentLength); len(decodeContentSize) > 0 {
-			_, err := strconv.Atoi(decodeContentSize)
-			if err != nil {
-				h.logAndSendError(w, "cannot parse decode content length information", reqInfo,
-					errors.GetAPIError(errors.ErrMissingContentLength))
-				return
-			}
-		} else {
-			h.logAndSendError(w, "expecting decode content length information", reqInfo,
-				errors.GetAPIError(errors.ErrMissingContentLength))
-			return
-		}
-		chunkReader, err := newSignV4ChunkedReader(r)
-		if err != nil {
-			h.logAndSendError(w, "cannot initialize chunk reader", reqInfo, err)
-			return
-		}
-		params.Reader = chunkReader
-	}
-
 	params.CopiesNumbers, err = h.pickCopiesNumbers(metadata, bktInfo.LocationConstraint)
 	if err != nil {
 		h.logAndSendError(w, "invalid copies number", reqInfo, err)
@@ -275,8 +260,8 @@ func (h *handler) PutObjectHandler(w http.ResponseWriter, r *http.Request) {
 
 	extendedObjInfo, err := h.obj.PutObject(ctx, params)
 	if err != nil {
-		_, err2 := io.Copy(io.Discard, r.Body)
+		_, err2 := io.Copy(io.Discard, body)
-		err3 := r.Body.Close()
+		err3 := body.Close()
 		h.logAndSendError(w, "could not upload object", reqInfo, err, zap.Errors("body close errors", []error{err2, err3}))
 		return
 	}
@@ -339,6 +324,28 @@ func (h *handler) PutObjectHandler(w http.ResponseWriter, r *http.Request) {
 	middleware.WriteSuccessResponseHeadersOnly(w)
 }
 
+func (h *handler) getBodyReader(r *http.Request) (io.ReadCloser, error) {
+	if !api.IsSignedStreamingV4(r) {
+		return r.Body, nil
+	}
+
+	decodeContentSize := r.Header.Get(api.AmzDecodedContentLength)
+	if len(decodeContentSize) == 0 {
+		return nil, errors.GetAPIError(errors.ErrMissingContentLength)
+	}
+
+	if _, err := strconv.Atoi(decodeContentSize); err != nil {
+		return nil, fmt.Errorf("%w: parse decoded content length: %s", errors.GetAPIError(errors.ErrMissingContentLength), err.Error())
+	}
+
+	chunkReader, err := newSignV4ChunkedReader(r)
+	if err != nil {
+		return nil, fmt.Errorf("initialize chunk reader: %w", err)
+	}
+
+	return chunkReader, nil
+}
+
 func formEncryptionParams(r *http.Request) (enc encryption.Params, err error) {
 	sseCustomerAlgorithm := r.Header.Get(api.AmzServerSideEncryptionCustomerAlgorithm)
 	sseCustomerKey := r.Header.Get(api.AmzServerSideEncryptionCustomerKey)