forked from gitea/gitea
122 lines
3.4 KiB
Go
122 lines
3.4 KiB
Go
// Copyright 2013 Martini Authors
|
|
// Copyright 2015 The Macaron Authors
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License"): you may
|
|
// not use this file except in compliance with the License. You may obtain
|
|
// a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
// License for the specific language governing permissions and limitations
|
|
// under the License.
|
|
|
|
package gzip
|
|
|
|
import (
|
|
"bufio"
|
|
"fmt"
|
|
"net"
|
|
"net/http"
|
|
"strings"
|
|
|
|
"github.com/klauspost/compress/gzip"
|
|
"gopkg.in/macaron.v1"
|
|
)
|
|
|
|
const (
|
|
_HEADER_ACCEPT_ENCODING = "Accept-Encoding"
|
|
_HEADER_CONTENT_ENCODING = "Content-Encoding"
|
|
_HEADER_CONTENT_LENGTH = "Content-Length"
|
|
_HEADER_CONTENT_TYPE = "Content-Type"
|
|
_HEADER_VARY = "Vary"
|
|
)
|
|
|
|
// Options represents a struct for specifying configuration options for the GZip middleware.
|
|
type Options struct {
|
|
// Compression level. Can be DefaultCompression(-1), ConstantCompression(-2)
|
|
// or any integer value between BestSpeed(1) and BestCompression(9) inclusive.
|
|
CompressionLevel int
|
|
}
|
|
|
|
func isCompressionLevelValid(level int) bool {
|
|
return level == gzip.DefaultCompression ||
|
|
level == gzip.ConstantCompression ||
|
|
(level >= gzip.BestSpeed && level <= gzip.BestCompression)
|
|
}
|
|
|
|
func prepareOptions(options []Options) Options {
|
|
var opt Options
|
|
if len(options) > 0 {
|
|
opt = options[0]
|
|
}
|
|
|
|
if !isCompressionLevelValid(opt.CompressionLevel) {
|
|
// For web content, level 4 seems to be a sweet spot.
|
|
opt.CompressionLevel = 4
|
|
}
|
|
return opt
|
|
}
|
|
|
|
// Gziper returns a Handler that adds gzip compression to all requests.
|
|
// Make sure to include the Gzip middleware above other middleware
|
|
// that alter the response body (like the render middleware).
|
|
func Gziper(options ...Options) macaron.Handler {
|
|
opt := prepareOptions(options)
|
|
|
|
return func(ctx *macaron.Context) {
|
|
if !strings.Contains(ctx.Req.Header.Get(_HEADER_ACCEPT_ENCODING), "gzip") {
|
|
return
|
|
}
|
|
|
|
headers := ctx.Resp.Header()
|
|
headers.Set(_HEADER_CONTENT_ENCODING, "gzip")
|
|
headers.Set(_HEADER_VARY, _HEADER_ACCEPT_ENCODING)
|
|
|
|
// We've made sure compression level is valid in prepareGzipOptions,
|
|
// no need to check same error again.
|
|
gz, err := gzip.NewWriterLevel(ctx.Resp, opt.CompressionLevel)
|
|
if err != nil {
|
|
panic(err.Error())
|
|
}
|
|
defer gz.Close()
|
|
|
|
gzw := gzipResponseWriter{gz, ctx.Resp}
|
|
ctx.Resp = gzw
|
|
ctx.MapTo(gzw, (*http.ResponseWriter)(nil))
|
|
|
|
// Check if render middleware has been registered,
|
|
// if yes, we need to modify ResponseWriter for it as well.
|
|
if _, ok := ctx.Render.(*macaron.DummyRender); !ok {
|
|
ctx.Render.SetResponseWriter(gzw)
|
|
}
|
|
|
|
ctx.Next()
|
|
|
|
// delete content length after we know we have been written to
|
|
gzw.Header().Del("Content-Length")
|
|
}
|
|
}
|
|
|
|
type gzipResponseWriter struct {
|
|
w *gzip.Writer
|
|
macaron.ResponseWriter
|
|
}
|
|
|
|
func (grw gzipResponseWriter) Write(p []byte) (int, error) {
|
|
if len(grw.Header().Get(_HEADER_CONTENT_TYPE)) == 0 {
|
|
grw.Header().Set(_HEADER_CONTENT_TYPE, http.DetectContentType(p))
|
|
}
|
|
return grw.w.Write(p)
|
|
}
|
|
|
|
func (grw gzipResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
|
|
hijacker, ok := grw.ResponseWriter.(http.Hijacker)
|
|
if !ok {
|
|
return nil, nil, fmt.Errorf("the ResponseWriter doesn't support the Hijacker interface")
|
|
}
|
|
return hijacker.Hijack()
|
|
}
|