How to use the keystone.pre function in keystone

const mainHash = 'ad807fa5016f97e62e7d';
const vendorHash = '158ebf10428e11d2ccc7';

import React from 'react';
import { renderToString } from 'react-dom/server';
import { match, RouterContext } from 'react-router';
import { Provider } from 'react-redux';
import store from '../app/src/store/store.js';
import { routes } from '../app/src/utils/routes.jsx';

const serverApiRoutes = {
  api: importRoutes('./api')
};

if (isDeveloping) {
  keystone.pre('routes', webpackMiddleware(compiler, {
    noInfo: true,
    publicPath: config.output.publicPath
  }));

  keystone.pre('routes', webpackHotMiddleware(compiler, {
    log: console.log // eslint-disable-line
  }));
}

exports = module.exports = function (app) {
  app.use(webpackMiddleware(compiler, {
    noInfo: true,
    publicPath: config.output.publicPath
  }));

  app.use(webpackHotMiddleware(compiler, {

* http://expressjs.com/api.html#app.VERB
 */

var keystone = require('keystone');
var middleware = require('./middleware');
var importRoutes = keystone.importer(__dirname);

var exec = require('child_process').exec;
var fs = require('fs');
var async = require('async');
//var Promise = require('node-promise'); //Promises to handle asynchonous callbacks.
var Promise = require('mpromise');

// Common Middleware
keystone.pre('routes', middleware.initLocals);
keystone.pre('render', middleware.flashMessages);

// Import Route Controllers
var routes = {
	views: importRoutes('./views'),
	api: importRoutes('./api')
};

// Setup Route Bindings
exports = module.exports = function(app) {
	
	// Views
	app.get('/', routes.views.index);
	app.get('/blog/:category?', routes.views.blog);
	app.get('/blog/post/:post', routes.views.post);
	app.get('/gallery', routes.views.gallery);
	app.all('/contact', routes.views.contact);

var _ = require('underscore'),
	keystone = require('keystone'),
	middleware = require('./middleware'),
	importRoutes = keystone.importer(__dirname);

// Common Middleware
keystone.pre('routes', middleware.initErrorHandlers);
keystone.pre('routes', middleware.initLocals);
keystone.pre('routes', middleware.loadSponsors);
keystone.pre('render', middleware.flashMessages);

// Handle 404 errors
keystone.set('404', function(req, res, next) {
	res.notfound();
});

// Handle other errors
keystone.set('500', function(err, req, res, next) {
	var title, message;
	if (err instanceof Error) {
		message = err.message;
		err = err.stack;
	}

var keystone = require('keystone'),
	_ = require('underscore'),
	globals = require('../lib/globals'),
	middleware = require('./middleware'),
	importRoutes = keystone.importer(__dirname);

// Common Middleware
keystone.pre('routes', middleware.initErrorHandlers);
keystone.pre('routes', middleware.init);
keystone.pre('routes', middleware.loadTags);
keystone.pre('routes', middleware.countTopics);
keystone.pre('render', middleware.flashMessages);

// Handle 404 errors
keystone.set('404', function(req, res, next) {
	res.notfound();
});

// Handle other errors
keystone.set('500', function(err, req, res, next) {
	var title, message;
	if (err instanceof Error) {
		message = err.message;
		err = err.stack;

* form submissions, rendering the view template, etc).
 *
 * Bind each route pattern your application should respond to in the function
 * that is exported from this module, following the examples below.
 *
 * See the Express application routing documentation for more information:
 * http://expressjs.com/api.html#app.VERB
 */

var keystone = require('keystone');
var middleware = require('./middleware');
var importRoutes = keystone.importer(__dirname);

// Common Middleware
keystone.pre('routes', middleware.initLocals);
keystone.pre('render', middleware.flashMessages);

// Import Route Controllers
var routes = {
	views: importRoutes('./views'),
};

// Setup Route Bindings
exports = module.exports = function (app) {
	// Views
	// app.get('/', routes.views.index);
	// app.get('/blog/:category?', routes.views.blog);
	// app.get('/blog/post/:post', routes.views.post);
	// app.get('/gallery', routes.views.gallery);

	// NOTE: To protect a route so that only admins can see it, use the requireUser middleware:
	// app.get('/protected', middleware.requireUser, routes.views.protected);

exports = module.exports = app => {

  // before any route, load in the locals
  keystone.pre('routes', initLocals);

  // redirects
  Object.keys(redirectData)
    .forEach((key) => app.get(`/${key}`, controllers.view.redirect));

  /*****************************************
   *****************************************
    API Routes
   *****************************************
   *****************************************/

  if(authOn) {
    app.post('/api/login',  controllers.login.loginAction);
    app.all('/api/logout', controllers.login.logoutAction);

    // login page view route