lewis.moe
1package models
2
3import (
4 "encoding/base64"
5 "strings"
6)
7
8// SecretMask replaces secret values in strings with "***".
9type SecretMask struct {
10 replacer *strings.Replacer
11}
12
13// NewSecretMask creates a mask for the given secret values.
14// Also registers base64-encoded variants of each secret.
15func NewSecretMask(values []string) *SecretMask {
16 var pairs []string
17
18 for _, value := range values {
19 if value == "" {
20 continue
21 }
22
23 pairs = append(pairs, value, "***")
24
25 b64 := base64.StdEncoding.EncodeToString([]byte(value))
26 if b64 != value {
27 pairs = append(pairs, b64, "***")
28 }
29
30 b64NoPad := strings.TrimRight(b64, "=")
31 if b64NoPad != b64 && b64NoPad != value {
32 pairs = append(pairs, b64NoPad, "***")
33 }
34 }
35
36 if len(pairs) == 0 {
37 return nil
38 }
39
40 return &SecretMask{
41 replacer: strings.NewReplacer(pairs...),
42 }
43}
44
45// Mask replaces all registered secret values with "***".
46func (m *SecretMask) Mask(input string) string {
47 if m == nil || m.replacer == nil {
48 return input
49 }
50 return m.replacer.Replace(input)
51}