check-cert-expiration

check-cert-expiration

Queries an SSL/TLS server and reports when its certificate expires.

Installation

npm install --global check-cert-expiration # for the command line utility
npm install --save check-cert-expiration # for the library function

Command Line Interface

The check-cert-expiration script accepts 1 or more URLs as command line arguments and prints the results.

Examples

Happy path (return code is 0):

$ check-cert-expiration tomcort.com github.com
host=tomcort.com port=443 valid_to=2018-03-09T10:34:20.000Z daysLeft=89
host=github.com port=443 valid_to=2018-05-17T12:00:00.000Z daysLeft=159

Error path (return code is 1):

$ check-cert-expiration does-not-exist.example.com
host=does-not-exist.example.com port=443 message="getaddrinfo ENOTFOUND"

API

checkCertExpiration(targetUrl, callback)

Parameters:

• targetUrl - a server URL (e.g. https://www.tomcort.com/) or hostname (e.g. tomcort.com).
• callback - a callback function which accepts (err, result). result will have the following properties:
• host - hostname of the host checked.
• port - TCP port number of the host checked,
• valid_to - ISO8601 timestamp string.
• daysLeft - how many days left until the certificate expires.

Examples

"use strict";

var checkCertExpiration = require('check-cert-expiration');

checkCertExpiration('tomcort.com', function (err, result) {
    if (err) {
        console.error(err);
        return;
    }
    console.log("%s days until the certificate expires for %s:%s", result.daysLeft, result.host, result.port);
});

Testing

npm test

License

See LICENSE.md