@himorishige/noren-core/dist/masking.js

Core PII detection, masking, and tokenization library built on Web Standards

export function defaultMask(h, keepLast4) {
    if (keepLast4) {
        if (h.type === 'credit_card') {
            const last4 = h.value.replace(/\D/g, '').slice(-4);
            return `**** **** **** ${last4}`;
        }
        else {
            // For other types, preserve last 4 characters
            const last4 = h.value.slice(-4);
            return `[REDACTED:${h.type}]${last4}`;
        }
    }
    if (h.type === 'phone_e164')
        return h.value.replace(/\d/g, '•');
    return `[REDACTED:${h.type}]`;
}