diff options
Diffstat (limited to 'vendor/github.com/emicklei/go-restful/compress.go')
-rw-r--r-- | vendor/github.com/emicklei/go-restful/compress.go | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/vendor/github.com/emicklei/go-restful/compress.go b/vendor/github.com/emicklei/go-restful/compress.go new file mode 100644 index 000000000..220b37712 --- /dev/null +++ b/vendor/github.com/emicklei/go-restful/compress.go @@ -0,0 +1,123 @@ +package restful + +// Copyright 2013 Ernest Micklei. All rights reserved. +// Use of this source code is governed by a license +// that can be found in the LICENSE file. + +import ( + "bufio" + "compress/gzip" + "compress/zlib" + "errors" + "io" + "net" + "net/http" + "strings" +) + +// OBSOLETE : use restful.DefaultContainer.EnableContentEncoding(true) to change this setting. +var EnableContentEncoding = false + +// CompressingResponseWriter is a http.ResponseWriter that can perform content encoding (gzip and zlib) +type CompressingResponseWriter struct { + writer http.ResponseWriter + compressor io.WriteCloser + encoding string +} + +// Header is part of http.ResponseWriter interface +func (c *CompressingResponseWriter) Header() http.Header { + return c.writer.Header() +} + +// WriteHeader is part of http.ResponseWriter interface +func (c *CompressingResponseWriter) WriteHeader(status int) { + c.writer.WriteHeader(status) +} + +// Write is part of http.ResponseWriter interface +// It is passed through the compressor +func (c *CompressingResponseWriter) Write(bytes []byte) (int, error) { + if c.isCompressorClosed() { + return -1, errors.New("Compressing error: tried to write data using closed compressor") + } + return c.compressor.Write(bytes) +} + +// CloseNotify is part of http.CloseNotifier interface +func (c *CompressingResponseWriter) CloseNotify() <-chan bool { + return c.writer.(http.CloseNotifier).CloseNotify() +} + +// Close the underlying compressor +func (c *CompressingResponseWriter) Close() error { + if c.isCompressorClosed() { + return errors.New("Compressing error: tried to close already closed compressor") + } + + c.compressor.Close() + if ENCODING_GZIP == c.encoding { + currentCompressorProvider.ReleaseGzipWriter(c.compressor.(*gzip.Writer)) + } + if ENCODING_DEFLATE == c.encoding { + currentCompressorProvider.ReleaseZlibWriter(c.compressor.(*zlib.Writer)) + } + // gc hint needed? + c.compressor = nil + return nil +} + +func (c *CompressingResponseWriter) isCompressorClosed() bool { + return nil == c.compressor +} + +// Hijack implements the Hijacker interface +// This is especially useful when combining Container.EnabledContentEncoding +// in combination with websockets (for instance gorilla/websocket) +func (c *CompressingResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) { + hijacker, ok := c.writer.(http.Hijacker) + if !ok { + return nil, nil, errors.New("ResponseWriter doesn't support Hijacker interface") + } + return hijacker.Hijack() +} + +// WantsCompressedResponse reads the Accept-Encoding header to see if and which encoding is requested. +func wantsCompressedResponse(httpRequest *http.Request) (bool, string) { + header := httpRequest.Header.Get(HEADER_AcceptEncoding) + gi := strings.Index(header, ENCODING_GZIP) + zi := strings.Index(header, ENCODING_DEFLATE) + // use in order of appearance + if gi == -1 { + return zi != -1, ENCODING_DEFLATE + } else if zi == -1 { + return gi != -1, ENCODING_GZIP + } else { + if gi < zi { + return true, ENCODING_GZIP + } + return true, ENCODING_DEFLATE + } +} + +// NewCompressingResponseWriter create a CompressingResponseWriter for a known encoding = {gzip,deflate} +func NewCompressingResponseWriter(httpWriter http.ResponseWriter, encoding string) (*CompressingResponseWriter, error) { + httpWriter.Header().Set(HEADER_ContentEncoding, encoding) + c := new(CompressingResponseWriter) + c.writer = httpWriter + var err error + if ENCODING_GZIP == encoding { + w := currentCompressorProvider.AcquireGzipWriter() + w.Reset(httpWriter) + c.compressor = w + c.encoding = ENCODING_GZIP + } else if ENCODING_DEFLATE == encoding { + w := currentCompressorProvider.AcquireZlibWriter() + w.Reset(httpWriter) + c.compressor = w + c.encoding = ENCODING_DEFLATE + } else { + return nil, errors.New("Unknown encoding:" + encoding) + } + return c, err +} |