Replaced: Use Greenlock Express v3

See https://git.rootprojects.org/root/greenlock-express.js

``js
"use strict";

var pkg = require("./package.json");
require("greenlock-express")
.init(function getConfig() {
// Greenlock Config

return {
package: { name: pkg.name, version: pkg.version },
maintainerEmail: pkg.author,

// put cluster on full throttle!
cloudnative: true
webscale: true
cluster: true
};
})
.serve(httpsWorker);

function httpsWorker(glx) {
// Serves on 80 and 443
// Get's SSL certificates magically!

glx.serveApp(function(req, res) {
res.end("Hello, Encrypted World!");
});
}
`

OLD STUFF BELOW

(Preserved for historical reference)

| A Root Project
| greenlock (lib)
| greenlock-cli
| greenlock-express
| greenlock-cluster
| greenlock-koa
| greenlock-hapi
|

greenlock-cluster

(previously letsencrypt-cluster)

Use automatic letsencrypt with node on multiple cores or even multiple machines.

- Take advantage of multi-core computing
- Process certificates in master
- Serve https from multiple workers
- Can work with any clustering strategy #1

Install

`bash
npm install --save greenlock-cluster@2.x
`

Usage

In a cluster environment you have some main file that boots your app
and then conditionally loads certain code based on whether that fork
is the master or just a worker.

In such a file you might want to define some of the options that need
to be shared between both the master and the worker, like this:

boot.js:

`javascript
"use strict";

var cluster = require("cluster");
var path = require("path");
var os = require("os");

var main;
var sharedOptions = {
webrootPath: path.join(os.tmpdir(), "acme-challenge"), // /tmp/acme-challenge
// used by le-challenge-fs, the default plugin

renewWithin: 14 24 60 60 1000, // 10 days before expiration

debug: true
};

if (cluster.isMaster) {
main = require("./master");
} else {
main = require("./worker");
}

main.init(sharedOptions);
`

Master

We think it makes the most sense to load greenlock in master.
This can prevent race conditions (see node-letsencrypt#45)
as only one process is writing the to file system or database at a time.

The main implementation detail here is approveDomains(options, certs, cb) for new domain certificates
and potentially agreeToTerms(opts, cb) for new accounts.

The master takes the same arguments as node-greenlock (challenge, store, etc),
plus a few extra (approveDomains... okay, just one extra):

master.js:

`javascript
'use strict';

var cluster = require('cluster');

module.exports.init = function (sharedOpts) {
var cores = require('os').cpus();
var leMaster = require('greenlock-cluster/master').create({
debug: sharedOpts.debug

// You MUST change this to 'https://acme-v02.api.letsencrypt.org/directory' in production
server: 'https://acme-staging-v02.api.letsencrypt.org/directory'
, version: 'draft-11' // Let's Encrypt v2

, renewWithin: sharedOpts.renewWithin

, webrootPath: sharedOpts.webrootPath

, approveDomains: function (masterOptions, certs, cb) {
// Do any work that must be done by master to approve this domain
// (in this example, it's assumed to be done by the worker)

var results = { domain: masterOptions.domain // required
, options: masterOptions // domains, email, agreeTos
, certs: certs }; // altnames, privkey, cert
cb(null, results);
}
});

cores.forEach(function () {
var worker = cluster.fork();
leMaster.addWorker(worker);
});
};
`

$3

All options are passed directly to node-greenlock
(in other works, leMaster is a greenlock instance),
but a few are only actually used by greenlock-cluster.

- leOptions.approveDomains(options, certs, cb) is special for greenlock-cluster, but will probably be included in node-greenlock in the future (no API change).

- leMaster.addWorker(worker) is added by greenlock-cluster and must be called for each new worker.

Worker

The worker takes _similar_ arguments to node-greenlock,
but only ones that are useful for determining certificate
renewal and for le.challenge.get.

If you want to a non-default le.challenge

worker.js:

`javascript
"use strict";

module.exports.init = function(sharedOpts) {
var leWorker = require("greenlock-cluster/worker").create({
debug: sharedOpts.debug,

renewWithin: sharedOpts.renewWithin,

webrootPath: sharedOpts.webrootPath,

// , challenge: require('le-challenge-fs').create({ webrootPath: '...', ... })

approveDomains: function(workerOptions, certs, cb) {
// opts = { domains, email, agreeTos, tosUrl }
// certs = { subject, altnames, expiresAt, issuedAt }

var results = {
domain: workerOptions.domains[0],
options: {
domains: workerOptions.domains
},
certs: certs
};

if (certs) {
// modify opts.domains to match the original request
// email is not necessary, because the account already exists
// this will only fail if the account has become corrupt
results.options.domains = certs.altnames;
cb(null, results);
return;
}

// This is where one would check one's application-specific database:
// 1. Lookup the domain to see which email it belongs to
// 2. Assign a default email if it isn't in the system
// 3. If the email has no le account, agreeToTerms will fire unless agreeTos is preset

results.options.email = "john.doe@example.com";
results.options.agreeTos = true; // causes agreeToTerms to be skipped
cb(null, results);
}
});

function app(req, res) {
res.end("Hello, World!");
}

var redirectHttps = require("redirect-https")();
var plainServer = require("http").createServer(leWorker.middleware(redirectHttps));
plainServer.listen(80);

var server = require("https").createServer(leWorker.httpsOptions, leWorker.middleware(app));
server.listen(443);
};
`

$3

node-greenlock is not used directly by the worker,
but certain options are shared because certain logic is duplicated.

- leOptions.renewWithin is shared so that the worker knows how earlier to request a new cert
- leOptions.renewBy is passed to le-sni-auto so that it staggers renewals between renewWithin (latest) and renewBy (earlier)
- leWorker.middleware(nextApp) uses greenlock/middleware for GET-ing http-01, hence sharedOptions.webrootPath
- leWorker.httpsOptions has a default localhost certificate and the SNICallback.

There are a few options that aren't shown in these examples, so if you need to change something
that isn't shown here, look at the code (it's not that much) or open an issue.

Message Passing

The master and workers will communicate through process.on('message', fn), process.send({}),
worker.on('message', fn)and worker.send({}).

All messages have a type property which is a string and begins with LE_`.
All other messages are ignored.