forked from yunionio/pkg
-
Notifications
You must be signed in to change notification settings - Fork 0
/
reader.go
121 lines (110 loc) · 2.76 KB
/
reader.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
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
// Copyright 2019 Yunion
//
// 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 multipart
import (
"bytes"
"crypto/rand"
"fmt"
"io"
"net/textproto"
"sort"
"strings"
)
type SReader struct {
body io.Reader
header string
tail string
boundary string
headOffset int
bodyEof bool
tailOffset int
}
var quoteEscaper = strings.NewReplacer("\\", "\\\\", `"`, "\\\"")
func escapeQuotes(s string) string {
return quoteEscaper.Replace(s)
}
func randomBoundary() string {
var buf [30]byte
_, err := io.ReadFull(rand.Reader, buf[:])
if err != nil {
panic(err)
}
return fmt.Sprintf("%x", buf[:])
}
func buildHeader(header textproto.MIMEHeader, boundary string) string {
var b bytes.Buffer
fmt.Fprintf(&b, "--%s\r\n", boundary)
keys := make([]string, 0, len(header))
for k := range header {
keys = append(keys, k)
}
sort.Strings(keys)
for _, k := range keys {
for _, v := range header[k] {
fmt.Fprintf(&b, "%s: %s\r\n", k, v)
}
}
fmt.Fprintf(&b, "\r\n")
return b.String()
}
func buildTail(boundary string) string {
return fmt.Sprintf("\r\n--%s--\r\n", boundary)
}
func NewReader(r io.Reader, fieldname, filename string) *SReader {
h := make(textproto.MIMEHeader)
h.Set("Content-Disposition",
fmt.Sprintf(`form-data; name="%s"; filename="%s"`,
escapeQuotes(fieldname), escapeQuotes(filename)))
h.Set("Content-Type", "application/octet-stream")
boundary := randomBoundary()
return &SReader{
body: r,
header: buildHeader(h, boundary),
tail: buildTail(boundary),
boundary: boundary,
headOffset: 0,
bodyEof: false,
tailOffset: 0,
}
}
func (r *SReader) FormDataContentType() string {
return "multipart/form-data; boundary=" + r.boundary
}
func (r *SReader) Read(p []byte) (n int, err error) {
read := 0
for read < len(p) && r.headOffset < len(r.header) {
p[read] = r.header[r.headOffset]
r.headOffset += 1
read += 1
}
if read < len(p) && !r.bodyEof {
n, err := r.body.Read(p[read:])
read += n
if err == io.EOF || n == 0 {
r.bodyEof = true
} else {
return read, err
}
}
for read < len(p) && r.tailOffset < len(r.tail) {
p[read] = r.tail[r.tailOffset]
r.tailOffset += 1
read += 1
}
if read == 0 && r.tailOffset >= len(r.tail) {
return 0, io.EOF
} else {
return read, nil
}
}