84 lines
1.6 KiB
Go
84 lines
1.6 KiB
Go
package codec
|
|
|
|
import (
|
|
"bytes"
|
|
"compress/gzip"
|
|
"io/ioutil"
|
|
|
|
css "git.loafle.net/overflow/server-go/socket"
|
|
)
|
|
|
|
type GZipCodec struct {
|
|
}
|
|
|
|
func (_ *GZipCodec) Encode(message []byte) ([]byte, error) {
|
|
var b bytes.Buffer
|
|
gWriter, err := gzip.NewWriterLevel(&b, gzip.BestSpeed)
|
|
if nil != err {
|
|
return nil, err
|
|
}
|
|
|
|
if _, err := gWriter.Write(message); nil != err {
|
|
return nil, err
|
|
}
|
|
if err := gWriter.Flush(); nil != err {
|
|
return nil, err
|
|
}
|
|
if err := gWriter.Close(); nil != err {
|
|
return nil, err
|
|
}
|
|
|
|
return b.Bytes(), nil
|
|
}
|
|
|
|
func (_ *GZipCodec) Decode(message []byte) ([]byte, error) {
|
|
gReader, err := gzip.NewReader(bytes.NewBuffer(message))
|
|
if nil != err {
|
|
return nil, err
|
|
}
|
|
defer gReader.Close()
|
|
|
|
b, err := ioutil.ReadAll(gReader)
|
|
if nil != err {
|
|
return nil, err
|
|
}
|
|
|
|
return b, nil
|
|
}
|
|
|
|
var gZipCodec = &GZipCodec{}
|
|
|
|
func NewCompressionCodecSelector(threshold int) CodecSelector {
|
|
return &compressionCodecSelector{
|
|
threshold: threshold,
|
|
}
|
|
}
|
|
|
|
type compressionCodecSelector struct {
|
|
threshold int
|
|
}
|
|
|
|
func (cs *compressionCodecSelector) Encode(message []byte) (messageType int, encMessage []byte, err error) {
|
|
switch {
|
|
case cs.threshold < len(message):
|
|
messageType = css.BinaryMessage
|
|
encMessage, err = gZipCodec.Encode(message)
|
|
default:
|
|
messageType = css.TextMessage
|
|
encMessage, err = DefaultCodec.Encode(message)
|
|
}
|
|
|
|
return
|
|
}
|
|
|
|
func (cs *compressionCodecSelector) Decode(messageType int, message []byte) (decMessage []byte, err error) {
|
|
switch messageType {
|
|
case css.BinaryMessage:
|
|
decMessage, err = gZipCodec.Decode(message)
|
|
default:
|
|
decMessage, err = DefaultCodec.Decode(message)
|
|
}
|
|
|
|
return
|
|
}
|