-
Notifications
You must be signed in to change notification settings - Fork 0
/
gziphandler.go
103 lines (85 loc) · 2.6 KB
/
gziphandler.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
// Copyright (c) 2022 Gobalsky Labs Limited
//
// Use of this software is governed by the Business Source License included
// in the LICENSE.ZETA file and at https://www.mariadb.com/bsl11.
//
// Change Date: 18 months from the later of the date of the first publicly
// available Distribution of this version of the repository, and 25 June 2022.
//
// On the date above, in accordance with the Business Source License, use
// of this software will be governed by version 3 or later of the GNU General
// Public License.
package rest
import (
"compress/gzip"
"net/http"
"strings"
"sync"
"github.com/zeta-protocol/zeta/logging"
)
type gzipResponseWriter struct {
http.ResponseWriter
w *gzip.Writer
statusCode int
headerWritten bool
}
var pool = sync.Pool{
New: func() interface{} {
w, _ := gzip.NewWriterLevel(nil, gzip.BestSpeed)
return &gzipResponseWriter{
w: w,
}
},
}
func (gzr *gzipResponseWriter) WriteHeader(statusCode int) {
gzr.statusCode = statusCode
gzr.headerWritten = true
if gzr.statusCode != http.StatusNotModified && gzr.statusCode != http.StatusNoContent {
gzr.ResponseWriter.Header().Del("Content-Length")
gzr.ResponseWriter.Header().Set("Content-Encoding", "gzip")
}
gzr.ResponseWriter.WriteHeader(statusCode)
}
func (gzr *gzipResponseWriter) Write(b []byte) (int, error) {
if _, ok := gzr.Header()["Content-Type"]; !ok {
// If no content type, apply sniffing algorithm to un-gzipped body.
gzr.ResponseWriter.Header().Set("Content-Type", http.DetectContentType(b))
}
if !gzr.headerWritten {
// This is exactly what Go would also do if it hasn't been written yet.
gzr.WriteHeader(http.StatusOK)
}
return gzr.w.Write(b)
}
func (gzr *gzipResponseWriter) Flush() {
if gzr.w != nil {
gzr.w.Flush()
}
if fw, ok := gzr.ResponseWriter.(http.Flusher); ok {
fw.Flush()
}
}
func newGzipHandler(logger logging.Logger, fn http.HandlerFunc) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
if !strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
fn(w, r)
return
}
gzr := pool.Get().(*gzipResponseWriter)
gzr.statusCode = 0
gzr.headerWritten = false
gzr.ResponseWriter = w
gzr.w.Reset(w)
defer func() {
// gzr.w.Close will write a footer even if no data has been written.
// StatusNotModified and StatusNoContent expect an empty body so don't close it.
if gzr.statusCode != http.StatusNotModified && gzr.statusCode != http.StatusNoContent {
if err := gzr.w.Close(); err != nil {
logger.Error("Failed to Gzip output from REST proxy", logging.Error(err))
}
}
pool.Put(gzr)
}()
fn(gzr, r)
}
}