Example files on how to use ES6 generators in your code to reduce callback nesting

express-server-generator.js

'use strict';
/* 
 * Express server using ES6 generators
 * Use node 0.11
 * run with node --harmony express-server-generator.js 
 */
var Q    = require('q'),
    HTTP = require('q-io/http'),
    express = require('express'),
    http = require('http');

var app = express();
app.set('port', process.env.PORT || 3001);
app.use(express.favicon());
app.use(express.logger('dev'));
app.use(express.bodyParser());
app.use(express.methodOverride());
app.use(express.cookieParser());
app.use(app.router);

// development only
if ('development' == app.get('env')) {
  app.use(express.errorHandler());
}

app.get('/foo', Q.async(function* (req, res) {
  // I know this could be piped with 'traditional' means also, but in a real world case you would do async database etc calls here
  var resp = yield HTTP.read(path);
  res.send(resp.toString());
}));

http.createServer(app).listen(app.get('port'), function() {
  console.log('Express server listening on port ' + app.get('port'));
});

request-generator.js

'use strict';
/* 
 * HTTP request using ES6 generators
 * Use node 0.11
 * run with node --harmony request-generator.js 
 */
 
var Q    = require('q'),
    HTTP = require('q-io/http');


var request = Q.async(function* (path) {
  var response = yield HTTP.read(path);
  return response;
});


request('http://www.example.com').then(function(resp) {
  console.log(resp.toString());
});