README
¶
peekmask
A simple Go library for masking parts of strings with full UTF-8 support (including Japanese and emoji).
Features
- Mask strings while keeping prefix and suffix visible
- Full UTF-8 support (Japanese, emoji, and other multi-byte characters)
- Customizable mask character
- Minimum mask ratio setting (for security)
- Simple and easy-to-use API
Installation
go get github.com/SpringMT/peekmask
Usage
Simple Usage
Mask a string with default settings (use * as mask):
package main
import (
"fmt"
"github.com/SpringMT/peekmask"
)
func main() {
masked := peekmask.Mask("1234567890", 2, 3)
fmt.Println(masked) // Output: 12*****890
masked = peekmask.Mask("メールアドレス", 2, 2)
fmt.Println(masked) // Output: メー***レス
}
Custom Configuration
Create a Masker with custom settings:
package main
import (
"fmt"
"github.com/SpringMT/peekmask"
)
func main() {
// Create a Masker with custom settings
masker := peekmask.New(
'■', // Mask character
3, // Number of characters to keep from the start
3, // Number of characters to keep from the end
0.4, // Minimum mask ratio (40%)
)
masked := masker.Mask("1234567890")
fmt.Println(masked) // Output: 123■■■■890
masked = masker.Mask("こんにちは世界")
fmt.Println(masked) // Output: ■■■■■■■
}
API
Mask(s string, prefixLength, suffixLength int) string
Masks a string using default settings.
MaskChar:'*'MinMaskRatio:0.3
type Masker
A struct that holds the configuration for masking.
MaskChar: The character used for masking (e.g.,'*','■')PrefixLength: Number of characters to keep from the startSuffixLength: Number of characters to keep from the endMinMaskRatio: Minimum masking ratio (0.0-1.0)
New(maskChar rune, prefixLength, suffixLength int, minMaskRatio float64) *Masker
Creates a new Masker with custom settings.
(m *Masker) Mask(s string) string
Masks a string based on the configuration.
About Minimum Mask Ratio
MinMaskRatio ensures that if the masking ratio falls below the specified value, all characters will be masked instead.
Example:
masker := peekmask.New('*', 4, 4, 0.5)
// For string "1234567890" (10 characters)
// Masked characters: 10 - 4 - 4 = 2 characters
// Mask ratio: 2/10 = 0.2 (20%)
// Since 0.2 < 0.5, all characters will be masked
masked := masker.Mask("1234567890")
fmt.Println(masked) // Output: **********
This ensures that even with short strings or configurations that would mask only a few characters, the information is still protected.
Testing
go test -v
Benchmarks:
go test -bench=.
License
MIT License
Documentation
¶
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
Types ¶
type Masker ¶
type Masker struct {
// MaskChar is the character used for masking
MaskChar rune
// PrefixLength is the number of characters to keep from the start
PrefixLength int
// SuffixLength is the number of characters to keep from the end
SuffixLength int
// MinMaskRatio is the minimum masking ratio (0.0-1.0)
// If the masking ratio falls below this value, all characters will be masked
MinMaskRatio float64
}
Masker holds the configuration for masking strings
func Default ¶
func Default() *Masker
Default returns a Masker with default settings MaskChar: '*', PrefixLength: 2, SuffixLength: 2, MinMaskRatio: 0.3
Source Files