PhantomJS SEO HTML snapshot server - for AJAX crawling / JavaScript SEO

seo-server.js

/*
 * SEO server
 *
 * Generates and serves HTML snapshots for crawlers, esp. GoogleBot.
 * See https://developers.google.com/webmasters/ajax-crawling/docs/specification
 *
 * Note: This is run by phantonjs, not node. See http://phantomjs.org
 *
 */
var system = require('system')
var webpage = require('webpage')
var webserver = require('webserver')
 
// load config
var env = (system.env.NODE_ENV == 'production') ? 'prod' : 'dev'
var conf = require('../../conf/configs')[env]
var port = conf.seo.port || 8888
var targetBaseUrl = conf.web.domain
 
var render = function(url, done) {
    var page = webpage.create()
 
    // configure headless browser
    page.settings.loadImages = false
    page.settings.localToRemoteUrlAccessEnabled = true
 
    page.onCallback = function() {
        done(null, page.content)
        page.close()
    }
 
    page.open(url, function(status) {
        if (status != 'success') {
            done(status)
            page.close()
        }
    })
}
 
// kick off the server
var server = webserver.create()
server.listen(port, function(req, res) {
    var url = req.url
 
    // only GET allowed
    if (req.method != 'GET') {
        console.error('Deny request method', req.method, url)
        res.statusCode = 405
        res.write('')
        res.close()
        return
    }
 
    var escapedFragment = /[&\?]_escaped_fragment_=([^&]*)/
    var match = url.match(escapedFragment)
    if (!match) {
        console.error('Deny request', url)
        res.statusCode = 400
        res.write('')
        res.close()
        return
    }
 
    var prettyUrl = url.replace(escapedFragment, '')
    var hashFragment = match[1] 
    if (hashFragment) {
        prettyUrl += '#!' + unescape(hashFragment)
    }
 
    var targetUrl = targetBaseUrl + prettyUrl
    console.log('Fetching', targetUrl, '(was', url + ')', req.headers['user-agent'])
 
    render(targetUrl, function(err, html) {
        if (err) {
            console.error('Failed to load page', targetUrl)
            res.statusCode = 500
            res.write('')
            res.close()
            return
        }
        res.statusCode = 200
        res.write(html)
        res.close()
        console.log('Served page', targetUrl)
    })
})
 
console.info('Listening on port', port, 'targeting', targetBaseUrl)

var conf = require('../../conf/configs')[env]
which one conf file defined! i did'nt understand.
please help me.