sslko/dist/convert-peer-certificate.js

A simple tool to check SSL/TLS certificate information for a given domain.

import { DAY_IN_MILLISECOND } from "./constants.js";
/**
 * Calculates the number of days between two dates.
 * @param validFrom
 * @param validTo
 */
function getDaysTotal(validFrom, validTo) {
    return Math.ceil(Math.abs(validFrom.getTime() - validTo.getTime()) / DAY_IN_MILLISECOND);
}
/**
 * Calculates the number of days remaining until the certificate expires.
 * - can be negative if the certificate is already expired
 * @param validTo
 */
function getDaysLeft(validTo) {
    return Math.ceil((validTo.getTime() - Date.now()) / DAY_IN_MILLISECOND);
}
export function convertPeerCertificate(certificate) {
    const { valid_from, valid_to, pubkey, raw, ...rest } = certificate;
    // Remove issuerCertificate to avoid circular reference
    delete rest.issuerCertificate;
    return {
        validFromDate: new Date(valid_from),
        validToDate: new Date(valid_to),
        expired: new Date(valid_to).getTime() < Date.now(),
        daysLeft: getDaysLeft(new Date(valid_to)),
        daysTotal: getDaysTotal(new Date(valid_from), new Date(valid_to)),
        validFor: certificate.subjectaltname
            ? certificate.subjectaltname.replace(/DNS:|IP Address:/g, "").split(", ")
            : undefined,
        pubkey: Buffer.isBuffer(pubkey) ? pubkey.toString("base64") : undefined,
        raw: Buffer.isBuffer(raw) ? raw.toString("base64") : undefined,
        ...rest,
    };
}