Add domains to NodeJS Express http server on the fly

Question

I'm hosting multiple domains each running the same node app using Express vhost. I start them all using http.createServer

var app = express(); 
require('./app.js')(function(theApp) {

    app.use(express.vhost(domainName1, theApp));
    app.use(express.vhost(domainName2, theApp));
    app.use(express.vhost(domainName3, theApp));
    var d = domain.create();
    d.run(function(){
        http.createServer(app).listen(80);
    }); 
});

Is it possible to do the same thing but be able to add new domains to the server on the fly without having to restart the node application? IE pseudo-code:

• Do the above
• Wait for a Domains database record to be added
• Add a new vhost
• Restart necessary things

I want to make sure that users of the existing domains get as little down-time as possible (or even none) whilst the new domain is added.

Answer 1

The default Express behavior is to not discriminate based on the Host header. The vhost middleware adds this behavior. You probably could add more middleware whenever you discover a new domain you want to support… or you could just not discriminate on the Host header in the first place :

var app = express(); 
require('./app.js')(function(theApp) {
    app.use(theApp);
    var d = domain.create();
    d.run(function(){
        http.createServer(app).listen(80);
    }); 
});