refactor to go-restful

vendor/github.com/emicklei/go-restful/compressor_pools.go

@@ -0,0 +1,91 @@
+package restful
+
+// Copyright 2015 Ernest Micklei. All rights reserved.
+// Use of this source code is governed by a license
+// that can be found in the LICENSE file.
+
+import (
+	"bytes"
+	"compress/gzip"
+	"compress/zlib"
+	"sync"
+)
+
+// SyncPoolCompessors is a CompressorProvider that use the standard sync.Pool.
+type SyncPoolCompessors struct {
+	GzipWriterPool *sync.Pool
+	GzipReaderPool *sync.Pool
+	ZlibWriterPool *sync.Pool
+}
+
+// NewSyncPoolCompessors returns a new ("empty") SyncPoolCompessors.
+func NewSyncPoolCompessors() *SyncPoolCompessors {
+	return &SyncPoolCompessors{
+		GzipWriterPool: &sync.Pool{
+			New: func() interface{} { return newGzipWriter() },
+		},
+		GzipReaderPool: &sync.Pool{
+			New: func() interface{} { return newGzipReader() },
+		},
+		ZlibWriterPool: &sync.Pool{
+			New: func() interface{} { return newZlibWriter() },
+		},
+	}
+}
+
+func (s *SyncPoolCompessors) AcquireGzipWriter() *gzip.Writer {
+	return s.GzipWriterPool.Get().(*gzip.Writer)
+}
+
+func (s *SyncPoolCompessors) ReleaseGzipWriter(w *gzip.Writer) {
+	s.GzipWriterPool.Put(w)
+}
+
+func (s *SyncPoolCompessors) AcquireGzipReader() *gzip.Reader {
+	return s.GzipReaderPool.Get().(*gzip.Reader)
+}
+
+func (s *SyncPoolCompessors) ReleaseGzipReader(r *gzip.Reader) {
+	s.GzipReaderPool.Put(r)
+}
+
+func (s *SyncPoolCompessors) AcquireZlibWriter() *zlib.Writer {
+	return s.ZlibWriterPool.Get().(*zlib.Writer)
+}
+
+func (s *SyncPoolCompessors) ReleaseZlibWriter(w *zlib.Writer) {
+	s.ZlibWriterPool.Put(w)
+}
+
+func newGzipWriter() *gzip.Writer {
+	// create with an empty bytes writer; it will be replaced before using the gzipWriter
+	writer, err := gzip.NewWriterLevel(new(bytes.Buffer), gzip.BestSpeed)
+	if err != nil {
+		panic(err.Error())
+	}
+	return writer
+}
+
+func newGzipReader() *gzip.Reader {
+	// create with an empty reader (but with GZIP header); it will be replaced before using the gzipReader
+	// we can safely use currentCompressProvider because it is set on package initialization.
+	w := currentCompressorProvider.AcquireGzipWriter()
+	defer currentCompressorProvider.ReleaseGzipWriter(w)
+	b := new(bytes.Buffer)
+	w.Reset(b)
+	w.Flush()
+	w.Close()
+	reader, err := gzip.NewReader(bytes.NewReader(b.Bytes()))
+	if err != nil {
+		panic(err.Error())
+	}
+	return reader
+}
+
+func newZlibWriter() *zlib.Writer {
+	writer, err := zlib.NewWriterLevel(new(bytes.Buffer), gzip.BestSpeed)
+	if err != nil {
+		panic(err.Error())
+	}
+	return writer
+}