app.js

module.exports = function() {
    var express = require('express'),
        path = require('path'),
        config = require('./config.js'),
        fs = require('fs'),
        app = express(),
        version = require('./version.json');

    app.enable('trust proxy');
    app.set('trust proxy', 'loopback, linklocal, uniquelocal');
    app.use('/public', express.static(path.join(__dirname, 'public')));
    app.use('/fonts', express.static(path.join(__dirname, 'public/fonts')));

    if (process.env.RDB_HOST) {
        js = 'app.js'

        var root = __dirname + '/src/static/index.html'
        var html = fs.readFileSync(root).toString('utf-8');
        var analytics = '', drift = '';

        if (config.analytics && config.analytics.piwik && config.analytics.piwik.enabled) {
            analytics = fs.readFileSync(__dirname + '/src/static/piwik.tmpl').toString('utf-8');
            analytics = analytics.replace(new RegExp('__ENDPOINT__', 'g'), config.analytics.piwik.endpoint);
            analytics = analytics.replace(new RegExp('__DOMAIN__', 'g'), config.analytics.piwik.domain);
            analytics = analytics.replace(new RegExp('__SITEID__', 'g'), config.analytics.piwik.siteId);
            html = html.replace('__ANALYTICS__', analytics);
        }else{
            html = html.replace('__ANALYTICS__', '');
        }

        if (config.analytics && config.analytics.drift) {
            drift = fs.readFileSync(__dirname + '/src/static/drift.tmpl').toString('utf-8');
            drift = drift.replace('__DRIFT_VERSION__', config.analytics.drift.version);
            drift = drift.replace('__DRIFT_ID__', config.analytics.drift.id);
            html = html.replace('__DRIFT__', drift);
        }else{
            html = html.replace('__DRIFT__', '');
        }

        html = html.replace(new RegExp('__JS__', 'g'), js)

        app.use('/*', function (req, res, next) {
            res.setHeader('content-type', 'text/html');
            return res.sendFile(html);
        });
    } else {
        app.use('/*', function (req, res, next) {
            res.setHeader('content-type', 'text/html');
            return res.sendFile(path.join(__dirname, 'public/index.html'));
        });
    }

    app.get('/version.json', function(req, res, next) {
        return res.json(version);
    });

    // production error handler
    // no stacktraces leaked to user
    app.use(function(err, req, res, next) {
      res.status(err.status || 500);
      res.send({
          message: err.message,
          error: {}
      });
    });

    return app;
};