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