feat(compressor): deflate compress (#321)

* feat(compressor): deflate compress

1. Optimize compressor type definition. (Don't start with package name).
2. Implement deflate compressor and ut.

close #312

* refactor(compressor): revert compressor type definition

* refactor(compressor): remove fmt.Println in ut

* refactor(compressor): adjust the order of deflate compressor constants.

pkg/compressor/compressor.go

@@ -28,6 +28,7 @@ const (
 	CompressorLz4
 	CompressorDefault
 	CompressorZstd
+	CompressorDeflate
 	CompressorMax
 )
 

pkg/compressor/defalte_compress_test.go

@@ -0,0 +1,36 @@
+package compressor
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDeflateCompress(t *testing.T) {
+	ts := []struct {
+		text string
+	}{
+		{
+			text: "Don't communicate by sharing memory, share memory by communicating.",
+		},
+		{
+			text: "Concurrency is not parallelism.",
+		},
+		{
+			text: "The bigger the interface, the weaker the abstraction.",
+		},
+		{
+			text: "Documentation is for users.",
+		},
+	}
+
+	dc := &DeflateCompress{}
+	assert.EqualValues(t, CompressorDeflate, dc.GetCompressorType())
+
+	for _, s := range ts {
+		var data []byte = []byte(s.text)
+		dataCompressed, _ := dc.Compress(data)
+		ret, _ := dc.Decompress(dataCompressed)
+		assert.EqualValues(t, s.text, string(ret))
+	}
+}

pkg/compressor/deflater_compress.go → pkg/compressor/deflate_compress.go

@@ -16,3 +16,36 @@
  */
 
 package compressor
+
+import (
+	"bytes"
+	"compress/flate"
+	"io"
+
+	"github.com/seata/seata-go/pkg/util/log"
+)
+
+type DeflateCompress struct{}
+
+func (*DeflateCompress) Compress(data []byte) ([]byte, error) {
+	var buf bytes.Buffer
+	fw, err := flate.NewWriter(&buf, flate.BestCompression)
+	if err != nil {
+		log.Error(err)
+		return nil, err
+	}
+	defer fw.Close()
+	fw.Write(data)
+	fw.Flush()
+	return buf.Bytes(), nil
+}
+
+func (*DeflateCompress) Decompress(data []byte) ([]byte, error) {
+	fr := flate.NewReader(bytes.NewBuffer(data))
+	defer fr.Close()
+	return io.ReadAll(fr)
+}
+
+func (*DeflateCompress) GetCompressorType() CompressorType {
+	return CompressorDeflate
+}