feat: implement codec

codec/codec.go

@@ -0,0 +1,34 @@
+package codec
+
+import "io"
+
+type Header struct {
+	ServiceMethod string
+	Seq           uint64
+	Error         string
+}
+
+type Codec interface {
+	io.Closer
+	ReadHeader(*Header) error
+	ReadBody(interface{}) error
+	Write(*Header, interface{}) error
+}
+
+type NewCodecFunc func(closer io.ReadWriteCloser) Codec
+
+type Type string
+
+const (
+	MagicNumber      = 0x12E7165
+	GobType     Type = "application/gob"
+	JsonType    Type = "application/json"
+)
+
+var NewCodecFuncMap map[Type]NewCodecFunc
+
+func init() {
+	NewCodecFuncMap = make(map[Type]NewCodecFunc)
+	NewCodecFuncMap[GobType] = NewGobCodec
+	NewCodecFuncMap[JsonType] = NewJsonCodec
+}