ean-validator/index.js

Validator for Belgium EAN numbers

let uniqueArr = [];

function isValid(code) {
    // Validate length & starting with 54
    if(!code.match(/^[5]{1}[4]{1}[0-9]{16}$/)) return false;

    // Validate logic
    const sumPart = code.slice(0, -1).split('');
    const sumResult = sumPart.reduce((r, n, i) => i % 2 ? r + parseInt(n) : r + parseInt((n * 3)), 0);
    const nextTenFold = Math.ceil(sumResult/10) * 10;
    const checkingPart = parseInt(code.slice(-1));

    return (nextTenFold - sumResult) === checkingPart;
}

exports.isValid = isValid;