val := r.Trailer.Get(t.Key())
		if val != "" {
			w.Header().Set(t.Key(), val)
		}
		return
	}
	w.Header().Set(t.Key(), s)
}

// AddChecksumHeader will transfer any checksum value that has been checked.
func AddChecksumHeader(w http.ResponseWriter, c map[string]string) {
	for k, v := range c {
		if k == xhttp.AmzChecksumType {
			w.Header().Set(xhttp.AmzChecksumType, v)
			continue
		}

		redirectURL.RawQuery = v.Encode()
		writeRedirectSeeOther(w, redirectURL.String())
		return
	}

	// Add checksum header.
	if checksum != nil && checksum.Valid() {
		hash.AddChecksumHeader(w, checksum.AsMap())
	}

	// Decide what http response to send depending on success_action_status parameter
	switch successStatus {
	case "201":
		resp := encodeResponse(PostResponse{

	}

	if r.Header.Get(xhttp.AmzChecksumMode) == "ENABLED" && rs == nil {
		// AWS S3 silently drops checksums on range requests.
		cs, _ := objInfo.decryptChecksums(opts.PartNumber, r.Header)
		hash.AddChecksumHeader(w, cs)
	}

	if err = setObjectHeaders(ctx, w, objInfo, rs, opts); err != nil {
		writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
		return
	}

	// Set Parts Count Header