sensitive

Example of masking with a custom registered mask (ex: Belgian National Register Number)

package main

import (
	"errors"
	"log"
	"regexp"

	sensitive "github.com/ln80/struct-sensitive"
	"github.com/ln80/struct-sensitive/internal/option"
	"github.com/ln80/struct-sensitive/mask"
)

func main() {

	type Profile struct {
		Email    string `sensitive:"data,kind=email"`
		NRN      string `sensitive:"data,kind=be_nrn"`
		Fullname string `sensitive:"data"`
	}

	// Define the Belgian National Register Number (be_nrn) mask behavior.
	//
	// Assuming, based on business requirements, revealing the birth date is acceptable by default.
	//
	// You can evolve the mask behavior by adding options to the struct.
	// However, note that only the default options are used by the [sensitive.Mask] function.
	// Alternatively, you can define and apply the mask directly in your code if you need custom behavior for specific cases.
	type BeNRNConfig struct {
		RevealBirthDate bool
	}

	BeNRNRegex := regexp.MustCompile(`^(\d{2})\.(\d{2})\.(\d{2})-(\d{3})-(\d{2})$`)

	BeNRNMask := func(val string, opts ...func(*mask.Config[BeNRNConfig])) (masked string, err error) {
		cfg := mask.DefaultConfig(BeNRNConfig{
			RevealBirthDate: true,
		})
		option.Apply(&cfg, opts)

		matches := BeNRNRegex.FindStringSubmatch(val)
		if matches == nil {
			return "", errors.New("invalid BE_NRN format")
		}

		if !cfg.Kind.RevealBirthDate {
			masked = "**.**.**-***-**"
			return
		}
		masked = matches[1] + "." + matches[2] + "." + matches[3] + "-***-**"
		return
	}

	mask.Register("be_nrn", mask.DefaultMasker(BeNRNMask))

	p := Profile{
		Email:    "eric.prosacco@example.com",
		NRN:      "85.12.25-123-45",
		Fullname: "Eric Prosacco",
	}

	err := sensitive.Mask(&p)
	if err != nil {
		log.Fatal(err)
	}

	print(p)

}

Output:

Profile{
  Email: "*************@example.com",
  NRN: "85.12.25-***-**",
  Fullname: "*************",
}

Example of a basic usage

package main

import (
	"log"

	sensitive "github.com/ln80/struct-sensitive"
)

func main() {
	type Profile struct {
		Email    string `sensitive:"data"`
		Fullname string `sensitive:"data"`
		Role     string
	}

	p := Profile{
		Email:    "eric.prosacco@example.com",
		Fullname: "Eric Prosacco",
		Role:     "Teacher",
	}

	err := sensitive.Redact(&p)
	if err != nil {
		log.Fatal(err)
	}

	print(p)

}

Output:

Profile{
  Email: "*************************",
  Fullname: "*************",
  Role: "Teacher",
}

Example of a custom Redact function

package main

import (
	"log"
	"strings"

	sensitive "github.com/ln80/struct-sensitive"
)

func main() {
	type Profile struct {
		Email    string `sensitive:"data,kind=email"`
		Fullname string `sensitive:"data,kind=name"`
		Role     string
	}

	p := Profile{
		Email:    "eric.prosacco@example.com",
		Fullname: "Eric Prosacco",
		Role:     "Teacher",
	}

	err := sensitive.Redact(&p, func(rc *sensitive.RedactConfig) {
		rc.RedactFunc = func(fr sensitive.FieldReplace, val string) (string, error) {
			switch fr.Kind {
			case "email":
				return "ghost@unknown.net", nil
			case "name":
				return "Ghost", nil
			}
			return strings.Repeat("*", len(val)), nil
		}
	})
	if err != nil {
		log.Fatal(err)
	}

	print(p)

}

Output:

Profile{
  Email: "ghost@unknown.net",
  Fullname: "Ghost",
  Role: "Teacher",
}