caddy/middleware/gzip.go
2015-01-18 23:11:21 -07:00

41 lines
963 B
Go

package middleware
import (
"compress/gzip"
"io"
"net/http"
"strings"
)
func Gzip(p parser) Middleware {
return func(next http.HandlerFunc) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
if !strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
next(w, r)
return
}
w.Header().Set("Content-Encoding", "gzip")
gzipWriter := gzip.NewWriter(w)
defer gzipWriter.Close()
gz := gzipResponseWriter{Writer: gzipWriter, ResponseWriter: w}
next(gz, r)
}
}
}
// gzipResponeWriter wraps the underlying Write method
// with a gzip.Writer to compress the output.
type gzipResponseWriter struct {
io.Writer
http.ResponseWriter
}
// Write wraps the underlying Write method to do compression.
func (w gzipResponseWriter) Write(b []byte) (int, error) {
if w.Header().Get("Content-Type") == "" {
w.Header().Set("Content-Type", http.DetectContentType(b))
}
n, err := w.Writer.Write(b)
return n, err
}