add example for http2 via SPDY h2

examples/spdy.js

@@ -0,0 +1,69 @@
+'use strict';
+
+// npm install spdy@3.x
+
+//var Greenlock = require('greenlock-express')
+var Greenlock = require('../');
+
+var greenlock = Greenlock.create({
+
+  // Let's Encrypt v2 is ACME draft 11
+  version: 'draft-11'
+
+  // You MUST change 'acme-staging-v02' to 'acme-v02' in production
+, server: 'https://acme-staging-v02.api.letsencrypt.org/directory'
+
+  // You MUST change this to a valid email address
+, email: 'jon@example.com'
+
+  // You MUST NOT build clients that accept the ToS without asking the user
+, agreeTos: true
+
+  // You MUST change these to valid domains
+  // NOTE: all domains will validated and listed on the certificate
+, approveDomains: [ 'example.com', 'www.example.com' ]
+
+  // You MUST have access to write to directory where certs are saved
+  // ex: /home/foouser/acme/etc
+, configDir: require('path').join(require('os').homedir(), 'acme', 'etc')
+
+  // Get notified of important updates and help me make greenlock better
+, communityMember: true
+
+//, debug: true
+
+});
+
+
+
+////////////////////////
+// http-01 Challenges //
+////////////////////////
+
+// http-01 challenge happens over http/1.1, not http2
+var redirectHttps = require('redirect-https')();
+var acmeChallengeHandler = greenlock.middleware(redirectHttps);
+require('http').createServer(acmeChallengeHandler).listen(80, function () {
+  console.log("Listening for ACME http-01 challenges on", this.address());
+});
+
+
+
+////////////////////////
+// http2 via SPDY h2  //
+////////////////////////
+
+// spdy is a drop-in replacement for the https API
+var spdyOptions = Object.assign({}, greenlock.tlsOptions);
+spdyOptions.spdy = { protocols: [ 'h2', 'http/1.1' ], plain: false };
+var server = require('spdy').createServer(spdyOptions, require('express')().use('/', function (req, res) {
+  res.setHeader('Content-Type', 'text/html; charset=utf-8');
+  res.end('Hello, SPDY World!\n\n💚 🔒.js');
+}));
+server.on('error', function (err) {
+  console.error(err);
+});
+server.on('listening', function () {
+  console.log("Listening for SPDY/http2/https requests on", this.address());
+});
+server.listen(443);