func corsHandler(handler http.Handler) http.Handler {
	commonS3Headers := []string{
		xhttp.Date,
		xhttp.ETag,
		xhttp.ServerInfo,
		xhttp.Connection,
		xhttp.AcceptRanges,
		xhttp.ContentRange,
		xhttp.ContentEncoding,
		xhttp.ContentLength,
		xhttp.ContentType,
		xhttp.ContentDisposition,
		xhttp.LastModified,
		xhttp.ContentLanguage,
		xhttp.CacheControl,
		xhttp.RetryAfter,
		xhttp.AmzBucketRegion,

		IsLatest:         fi.IsLatest,
		DeleteMarker:     fi.Deleted,
		Size:             fi.Size,
		ModTime:          fi.ModTime,
		Legacy:           fi.XLV1,
		ContentType:      fi.Metadata["content-type"],
		ContentEncoding:  fi.Metadata["content-encoding"],
		NumVersions:      fi.NumVersions,
		SuccessorModTime: fi.SuccessorModTime,
		CacheControl:     fi.Metadata["cache-control"],
	}

	if exp, ok := fi.Metadata["expires"]; ok {

	req, err := newTestStreamingRequest(method, urlStr, contentLength, chunkSize, body)
	if err != nil {
		return nil, err
	}

	// Set custom encoding.
	req.Header.Set("content-encoding", contentEncoding)

	currTime := UTCNow()

	"response-expires":             xhttp.Expires,
	"response-content-type":        xhttp.ContentType,
	"response-cache-control":       xhttp.CacheControl,
	"response-content-encoding":    xhttp.ContentEncoding,
	"response-content-language":    xhttp.ContentLanguage,
	"response-content-disposition": xhttp.ContentDisposition,
}

const (
	compressionAlgorithmV1 = "golang/snappy/LZ77"