@handy-common-utils/misc-utils/dist/mask.js

Miscellaneous utilities

"use strict";
/* eslint-disable no-mixed-operators */
/* eslint-disable unicorn/prefer-string-slice */
Object.defineProperty(exports, "__esModule", { value: true });
exports.maskCreditCard = exports.maskAll = exports.maskFullName = exports.maskEmail = exports.masker = exports.mask = void 0;
/**
 * Mask the content of a string
 * @param input The input which could also be null or undefined
 * @param keepLeft Number of characters on the left to be kept in the output without masking.
 *                 Default value is 1.
 * @param keepRight Number of characters on the right to be kept in the output without masking.
 *                  Default value is 0.
 * @param minLength Minimal length of the string for keepLeft and keepRight to be effective.
 *                  If the input string is shorter than this length, the whole string would be masked.
 *                  Default value is 3.
 * @param maskLengthOrMaskString The string to be used for replacing the part in the input that needs to be masked,
 *                               or the length of the mask string if a fixed length is desired,
 *                               or null/undefined if the mask string should have the same length as the part to be masked.
 *                               Default value is null.
 * @param maskPattern The pattern to be repeated as the mask.
 *                    Default value is '*'.
 * @returns String with masked content
 */
function mask(input, keepLeft = 1, keepRight = 0, minLength = 3, maskLengthOrMaskString = null, maskPattern = '*') {
    if (minLength <= keepLeft + keepRight) {
        throw new Error(`Invalid parameter: expected minLength > keepLeft + keepRight, but got ${minLength}, ${keepLeft}, ${keepRight}`);
    }
    // pass through for undefined and null
    if (input == null) {
        return input;
    }
    if (input.length < minLength) {
        keepLeft = 0;
        keepRight = 0;
    }
    let maskString;
    if (typeof maskLengthOrMaskString === 'string') {
        maskString = maskLengthOrMaskString;
    }
    else {
        const maskLength = maskLengthOrMaskString == null ? (input.length - keepLeft - keepRight) : maskLengthOrMaskString;
        maskString = maskPattern.length === 1 ? maskPattern.repeat(maskLength) : maskPattern.repeat(maskLength / maskPattern.length + 1).substring(0, maskLength);
    }
    return `${input.substring(0, keepLeft)}${maskString}${input.substring(input.length - keepRight, input.length)}`;
}
exports.mask = mask;
/**
 * Create a mask function with pre-set parameters.
 * @example
 *   const maskApiKey = masker(2, 2, 10);
 *   const maskedString = maskApiKey(myApiKey);
 *
 * @param keepLeft Number of characters on the left to be kept in the output without masking.
 *                 Default value is 1.
 * @param keepRight Number of characters on the right to be kept in the output without masking.
 *                  Default value is 0.
 * @param minLength Minimal length of the string for keepLeft and keepRight to be effective.
 *                  If the input string is shorter than this length, the whole string would be masked.
 *                  Default value is 3.
 * @param maskLengthOrMaskString The string to be used for replacing the part in the input that needs to be masked,
 *                               or the length of the mask string if a fixed length is desired,
 *                               or null/undefined if the mask string should have the same length as the part to be masked.
 *                               Default value is null.
 * @param maskPattern The pattern to be repeated as the mask.
 *                    Default value is '*'.
 * @returns A mask function that has specified parameters as pre-set
 */
function masker(keepLeft, keepRight, minLength, maskLengthOrMaskString, maskPattern) {
    return input => mask(input, keepLeft, keepRight, minLength, maskLengthOrMaskString, maskPattern);
}
exports.masker = masker;
/**
 * Mask sensitive information in an email address while keeping some information for troubleshooting
 * @param email the email address which could also be null or undefined
 * @returns masked email address
 */
function maskEmail(email) {
    // pass through for undefined and null
    if (email == null) {
        return email;
    }
    const segments = email.split('@');
    if (segments.length === 2 && segments[0].length > 0) {
        const parts = segments[0].split('.');
        segments[0] = parts.map(s => mask(s, 1)).join('.');
        return segments.join('@');
    }
    // does not look like an email
    return mask(email);
}
exports.maskEmail = maskEmail;
/**
 * Mask sensitive information in the full name while keeping useful information for troubleshooting
 * @param name the full name which could also be null or undefined
 * @returns masked full name
 */
function maskFullName(name) {
    // pass through for undefined and null
    if (name == null) {
        return name;
    }
    const segments = name.split(' ');
    return segments.map(s => mask(s, 1)).join(' ');
}
exports.maskFullName = maskFullName;
/**
 * Replace each character of the input with '*'
 * @param input a string or null or undefined
 * @returns masked string or null or undefined
 */
function maskAll(input) {
    return mask(input, 0);
}
exports.maskAll = maskAll;
/**
 * Mask credit card number string
 * @param input credit card number string which could also be null or undefined
 * @returns Something like ****-****-****-1234, or null/undefined if the input is null/undefined
 */
function maskCreditCard(input) {
    if (input == null) {
        return input;
    }
    return '****-****-****-' + input.padStart(4, '*').slice(-4);
}
exports.maskCreditCard = maskCreditCard;