devcert - Development SSL made easy

So, running a local HTTPS server usually sucks. There's a range of approaches, each with their own tradeoff. The common one, using self-signed certificates, means having to ignore scary browser warnings for each project.

devcert makes the process easy. Want a private key and certificate file to use with your server? Just ask:

import * as https from 'https';
import * as express from 'express';
import getDevelopmentCertificate from 'devcert';

let app = express();

app.get('/', function (req, res) {
  res.send('Hello Secure World!');
});

getDevelopmentCertificate('my-app', { installCertutil: true }).then((ssl) => {
  https.createServer(ssl, app).listen(3000);
});

Now open https://localhost:3000 and voila - your page loads with no scary warnings or hoops to jump through.

Certificates are cached by name, so two calls for getDevelopmentCertificate('foo') will return the same key and certificate.

installCertutil option

devcert currently takes a single option: installCertutil. If true, devcert will attempt to install some software necessary to tell Firefox (and Chrome, only on Linux) to trust your development certificates. This is not required, but without it, you'll need to tell Firefox to trust these certificates manually.

Thankully, Firefox makes this easy. There's a point-and-click wizard for importing and trusting a certificate, so if you don't provide installCertutil: true to devcert, devcert will instead automatically open Firefox and kick off this wizard for you. Simply follow the prompts to trust the certificate. Reminder: you'll only need to do this once per machine

Note: Chrome on Linux requires installCertutil: true, or else you'll face the scary browser warnings every time. Unfortunately, there's no way to tell Chrome on Linux to trust a certificate without install certutil.

The software installed varies by OS:

• Mac: brew install nss
• Linux: apt install libnss3-tools
• Windows: N/A

How it works

When you ask for a development certificate, devcert will first check to see if it has run on this machine before. If not, it will create a root certificate authority and add it to your OS and various browser trust stores. You'll likely see password prompts from your OS at this point to authorize the new root CA. This is the only time you'll see these prompts.

This root certificate authority allows devcert to create a new SSL certificate whenever you want without needing to ask for elevated permissions again. It also ensures that browsers won't show scary warnings about untrusted certificates, since your OS and browsers will now trust devcert's certificates. The root CA certificate is unique to your machine only, and is generated on-the-fly when it is first installed.

Once devcert is sure that it has a root certificate authority installed, it will create a new SSL certificate & key pair for your app, signed by this root certificate authority. Since your browser & OS now trust the root authority, they'll trust the certificate for your app - no more scary warnings!

License

MIT © Dave Wasmer