server.js

'use strict';

const koa = require('koa')
      , app = koa()
      , json = require('koa-json')
      , serve = require('koa-static')
      , handlebars = require('koa-handlebars')
      , bodyParser = require('koa-bodyparser')
      , statuses = require('statuses');

// -------------------------------------------
//  custom status codes
// -------------------------------------------
statuses['440'] = 'The oath2 response token type is not "bearer".';

// -------------------------------------------
//  middleware
// -------------------------------------------

// error handling
app.use(function *(next) {
  try {
    yield next;
  } catch (err) {
    this.status = err.status || 500;
    this.body = err.message;
    this.app.emit('error', err, this);
  }
});

// app.use(function *(next) {
//   //This will set status and message
//   this.throw('Error Messagezzz', 500);
// }); 

// app.use(function *(next) {
//   //This will only set message
//   throw new Error('Error Messagerrrr');
// });

// for json responses : with pretty toggle
app.use(json({ pretty: false, param: 'pretty' }));
// basic body parser
app.use(bodyParser());
// serve static files
app.use(serve(__dirname + '/public'));
// handlebars config
app.use(handlebars({
    extension: ['hbs', 'handlebars'],
    defaultLayout: 'index',
    layoutsDir: 'app/templates',
    viewsDir: 'app/templates/views',
    partialsDir: 'app/templates/partials'
}));
// webpack dev server for LOCAL DEV ONLY
if (process.env.NODE_ENV !== 'production') {
  let webpackDevServer = require('koa-webpack-dev');
  app.use(webpackDevServer({
      config: './webpack.config.js'
  }));
}

// -------------------------------------------
//  init app
// -------------------------------------------

// initialize routes, set port
const routes = require('./app/routes')(app).next()
      , port = process.env.PORT || 5000;

app.listen(port);
console.log('Koa listening on port ' + port);