optimize seq, specifying that seq is stored in the only certain unknown

internal/msggateway/compressor.go

@@ -0,0 +1,46 @@
+package msggateway
+
+import (
+	"bytes"
+	"compress/gzip"
+	"io"
+
+	"github.com/OpenIMSDK/Open-IM-Server/pkg/utils"
+)
+
+type Compressor interface {
+	Compress(rawData []byte) ([]byte, error)
+	DeCompress(compressedData []byte) ([]byte, error)
+}
+type GzipCompressor struct {
+	compressProtocol string
+}
+
+func NewGzipCompressor() *GzipCompressor {
+	return &GzipCompressor{compressProtocol: "gzip"}
+}
+func (g *GzipCompressor) Compress(rawData []byte) ([]byte, error) {
+	gzipBuffer := bytes.Buffer{}
+	gz := gzip.NewWriter(&gzipBuffer)
+	if _, err := gz.Write(rawData); err != nil {
+		return nil, utils.Wrap(err, "")
+	}
+	if err := gz.Close(); err != nil {
+		return nil, utils.Wrap(err, "")
+	}
+	return gzipBuffer.Bytes(), nil
+}
+
+func (g *GzipCompressor) DeCompress(compressedData []byte) ([]byte, error) {
+	buff := bytes.NewBuffer(compressedData)
+	reader, err := gzip.NewReader(buff)
+	if err != nil {
+		return nil, utils.Wrap(err, "NewReader failed")
+	}
+	compressedData, err = io.ReadAll(reader)
+	if err != nil {
+		return nil, utils.Wrap(err, "ReadAll failed")
+	}
+	_ = reader.Close()
+	return compressedData, nil
+}