traefik/vendor/github.com/NYTimes/gziphandler/wrapper.go
2017-07-18 11:27:24 +02:00

58 lines
1.2 KiB
Go

package gziphandler
import (
"bufio"
"net"
"net/http"
)
const (
contentEncodingHeader = "Content-Encoding"
)
// ----------
// http.ResponseWriter
// http.Hijacker
type GzipWriter interface {
Header() http.Header
Write([]byte) (int, error)
WriteHeader(int)
Hijack() (net.Conn, *bufio.ReadWriter, error)
Close() error
SetResponseWriter(http.ResponseWriter)
setIndex(int)
setMinSize(int)
}
func (w *GzipResponseWriter) SetResponseWriter(rw http.ResponseWriter) {
w.ResponseWriter = rw
}
func (w *GzipResponseWriter) setIndex(index int) {
w.index = index
}
func (w *GzipResponseWriter) setMinSize(minSize int) {
w.minSize = minSize
}
// --------
type GzipResponseWriterWrapper struct {
GzipResponseWriter
}
func (g *GzipResponseWriterWrapper) Write(b []byte) (int, error) {
if g.gw == nil && isEncoded(g.Header()) {
return g.ResponseWriter.Write(b)
}
return g.GzipResponseWriter.Write(b)
}
func isEncoded(headers http.Header) bool {
header := headers.Get(contentEncodingHeader)
// According to https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Encoding,
// content is not encoded if the header 'Content-Encoding' is empty or equals to 'identity'.
return header != "" && header != "identity"
}