package util import ( "bytes" "compress/flate" "compress/gzip" "fmt" "io/ioutil" "strings" "github.com/chrislusf/seaweedfs/weed/glog" "github.com/klauspost/compress/zstd" ) func GzipData(input []byte) ([]byte, error) { buf := new(bytes.Buffer) w, _ := gzip.NewWriterLevel(buf, flate.BestSpeed) if _, err := w.Write(input); err != nil { glog.V(2).Infoln("error compressing data:", err) return nil, err } if err := w.Close(); err != nil { glog.V(2).Infoln("error closing compressed data:", err) return nil, err } return buf.Bytes(), nil } var zstdEncoder, _ = zstd.NewWriter(nil) func ZstdData(input []byte) ([]byte, error) { return zstdEncoder.EncodeAll(input, nil), nil } func DecompressData(input []byte) ([]byte, error) { if IsGzippedContent(input) { return ungzipData(input) } if IsZstdContent(input) { return unzstdData(input) } return input, fmt.Errorf("unsupported compression") } func ungzipData(input []byte) ([]byte, error) { buf := bytes.NewBuffer(input) r, _ := gzip.NewReader(buf) defer r.Close() output, err := ioutil.ReadAll(r) if err != nil { glog.V(2).Infoln("error uncompressing data:", err) } return output, err } var decoder, _ = zstd.NewReader(nil) func unzstdData(input []byte) ([]byte, error) { return decoder.DecodeAll(input, nil) } func IsGzippedContent(data []byte) bool { if len(data) < 2 { return false } return data[0] == 31 && data[1] == 139 } func IsZstdContent(data []byte) bool { if len(data) < 4 { return false } return data[3] == 0xFD && data[2] == 0x2F && data[1] == 0xB5 && data[0] == 0x28 } /* * Default not to compressed since compression can be done on client side. */func IsCompressableFileType(ext, mtype string) (shouldBeCompressed, iAmSure bool) { // text if strings.HasPrefix(mtype, "text/") { return true, true } // images switch ext { case ".svg", ".bmp", ".wav": return true, true } if strings.HasPrefix(mtype, "image/") { return false, true } // by file name extension switch ext { case ".zip", ".rar", ".gz", ".bz2", ".xz", ".zst": return false, true case ".pdf", ".txt", ".html", ".htm", ".css", ".js", ".json": return true, true case ".php", ".java", ".go", ".rb", ".c", ".cpp", ".h", ".hpp": return true, true case ".png", ".jpg", ".jpeg": return false, true } // by mime type if strings.HasPrefix(mtype, "application/") { if strings.HasSuffix(mtype, "zstd") { return false, true } if strings.HasSuffix(mtype, "xml") { return true, true } if strings.HasSuffix(mtype, "script") { return true, true } } if strings.HasPrefix(mtype, "audio/") { switch strings.TrimPrefix(mtype, "audio/") { case "wave", "wav", "x-wav", "x-pn-wav": return true, true } } return false, false }