app.js

var express = require('express');
var session = require('express-session');
var proxy = require('express-http-proxy');
var i18n = require('i18n');
var path = require('path');
var favicon = require('serve-favicon');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var routes = require('./conf/routes');
var conf = require('./conf/config');
var i18nConfig = require('./lib/i18n-config');
var zk_hosts = require('./lib/zk-hosts');
var kafka = require('./lib/kafka');
var accessLogger = require('./lib/logger').accessLogger;
var logger = require('./lib/logger').appLogger;

var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');

// uncomment after placing your favicon in /public
app.use(favicon(__dirname + '/public/favicon.ico'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));
app.use(cookieParser());
app.use(i18n.init);
app.use(i18nConfig.init);

app.use(session({
	name : 'kwm.sid',
	secret : 'kafka web monitor!',
	resave : false,
	saveUninitialized : false,
	cookie : conf.cookie
}));

app.use(function(req, res, next) {
	accessLogger.info([
		req.headers['x-forwarded-for'] || req.client.remoteAddress,
		req.method,
		req.url,
		res.statusCode,
		req.headers.referer || '-',
		req.headers['user-agent'] || '-'
	].join('\t'));
	next();
});
app.use(express.static(path.join(__dirname, 'public'), conf.static || {maxAge: 1000 * 60 * 60 * 24}));

var kafkaClient;

var middleware = function(req, res, next) {
	var id = req.query.id || req.cookies['zk-id'];
	try {
		if(kafkaClient) {
			if(id && zk_hosts.getZkHostsById(id) && id != kafkaClient.getId()) {
				logger.debug('Change kafkaClient. Current id:'+kafkaClient.getId()+', New id:'+id);
				kafkaClient.close();
				kafkaClient = new kafka.KafkaClient(id);
				res.cookie('zk-id', kafkaClient.getId(), { path: '/', httpOnly: true });
			}
		} else {
			kafkaClient = new kafka.KafkaClient(id);
			res.cookie('zk-id', kafkaClient.getId(), { path: '/', httpOnly: true });
		}

		req.kafkaClient = kafkaClient;
	} catch(err) {
		zk_hosts.loadZkHostsList();
		logger.error(err);
		throw err;
	}
	next();
};

// Init routes
var route, cfg;
for(var i = 0; i < routes.length; ++i) {
	cfg = routes[i];
	route = require(cfg.path);
	// use configed method
	app[cfg.method](cfg.url, middleware, route[cfg.fn]);
}

// catch 404 and forward to error handler
app.use(function(req, res, next) {
	var err = new Error('Not Found');
	err.status = 404;
	next(err);
});

// error handlers

// development error handler
// will print stacktrace
if (app.get('env') === 'development') {
	app.use(function(err, req, res, next) {
		res.status(err.status || 500);
		res.render('error', {
			message: err.message,
			error: err
		});
	});
}

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

module.exports = app;