README.md

panitizer (PAN sanitizer)

Go library (and command line tool) for scrubbing strings of PAN (Personal Account Number) data.

Installation

go get github.com/NickPresta/panitizer

Usage

package main

import (
    "github.com/NickPresta/panitizer"
)

func main() {
    cardNumber := "4242424242424242"
    fmt.Printf(panitizer.Replace(cardNumber)) // Prints ************4242
}

How Personal Account Numbers are identified

A string of digits is identified and masked as a credit card number if all of the following apply:

1. The digits follow the regular expression found here, which covers Visa, MasterCard, American Express, Diners Club, Discover, and JCB numbers.
2. The digits pass the Luhn Check.
3. The digits are separated only by spaces and/or dashes, or not separated at all. This allows for different sizes of groupings of digits. Note: A number broken by a line break is not detected as a credit card number.

Supported formats

* is used as the masking symbol in the following examples

original	credit card detected?	sanitized
4242 4242 4242 4242	Yes	**** **** **** 4242
4242-4242-4242-4242	Yes	**** **** **** 4242
42-42 42-42 42-42 42-42	Yes	**-** **-** **-** *2-42
4242.4242.4242.4242	No	4242.4242.4242.4242
4242x4242x4242x4242	No	4242x4242x4242x4242
4242 4242 4242 4242 4242 4242	Yes	**** **** **** 4242 4242 4242

Check out the tests for more examples.