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
|
package frontend
import (
"crypto/sha256"
"encoding/base64"
"io"
"io/fs"
"net/url"
"github.com/pkg/errors"
)
var Assets = &AssetCollection{
Scripts: make(map[string]Asset),
Stylesheets: make(map[string]Asset),
}
type Asset struct {
URL string
Base64SHA256 string
}
type AssetCollection struct {
Scripts map[string]Asset
Stylesheets map[string]Asset
}
func hashFile(filename string) ([]byte, error) {
file, err := Files.Open(filename)
if err != nil {
return nil, errors.WithMessagef(err, "could not open file %s", filename)
}
sum := sha256.New()
defer file.Close()
if _, err := io.Copy(sum, file); err != nil {
return nil, errors.WithMessagef(err, "could not hash file %s", filename)
}
return sum.Sum(nil), nil
}
func newAsset(filename string, hash []byte) Asset {
u, err := url.JoinPath("/", filename)
if err != nil {
panic(err)
}
return Asset{
URL: u,
Base64SHA256: base64.StdEncoding.EncodeToString(hash),
}
}
func hashScripts() error {
scripts, err := fs.Glob(Files, "static/**.js")
if err != nil {
return errors.WithMessage(err, "could not glob files")
}
for _, filename := range scripts {
hash, err := hashFile(filename)
if err != nil {
return err
}
Assets.Scripts[filename] = newAsset(filename, hash)
}
return nil
}
func hashStyles() error {
styles, err := fs.Glob(Files, "static/**.css")
if err != nil {
return errors.WithMessage(err, "could not glob files")
}
for _, filename := range styles {
hash, err := hashFile(filename)
if err != nil {
return err
}
Assets.Stylesheets[filename] = newAsset(filename, hash)
}
return nil
}
func Rehash() (err error) {
err = hashScripts()
if err != nil {
return err
}
err = hashStyles()
if err != nil {
return err
}
return nil
}
func init() {
err := Rehash()
if err != nil {
panic(err)
}
}
|