Node ExpressJS Contenful.js basic sync middleware example and routes

contentful-cache.js

'use strict'

var contentful = require('contentful'),
    util = require('util'),
    async = require('async'),
    fs = require('fs'),
    _ = require('lodash'),
    client = contentful.createClient({
        space: 'ctupzx1pv75n',
        accessToken: '601c31d2ec144e4d9e2dd4bd9771fef57ccf88d64ea722bca9ba2a749104d8a6'
    }),
    data = {},
    nextSyncToken = null,
    fileName = 'contentful.json',
    localCache = './app/data/'

function initialSync(obj) {
    data = obj
    nextSyncToken = obj.nextSyncToken
    saveToLocal(obj)
    console.log('Contentful: saved initial data')
}

function mergeData(obj) {
    data = _.merge(data, obj)
    nextSyncToken = obj.nextSyncToken
    saveToLocal(obj)
    console.log('Contentful: parsed new data')
}

function fetchLocal() {
    console.log('Contentful: fetching local data')
    fs.readFile(localCache + fileName, 'utf8', function(err, src) {
        data = JSON.parse(src)
        nextSyncToken = data.nextSyncToken
        console.log('Contentful: fetched local data')
    })
}

function fetchRemote(firstLoad) {
    console.log('Contentful: fetching remote data', nextSyncToken)
    var syncOptions = {
        resolveLinks: false
    }
    if (firstLoad) syncOptions.initial = true
    else syncOptions.nextSyncToken = nextSyncToken
    client.sync(syncOptions).then(function(result) {
        if (nextSyncToken === null) initialSync(result)
        else mergeData(result)
    }, function(err) {
        console.log('Contentful: error loading remote data', err)
    })
}

function saveToLocal(obj) {
    var newData = JSON.stringify(obj, null, 2)
    if (newData.length) fs.writeFile(localCache + fileName, newData)
}

module.exports = {
    init: function() {
        fs.exists(localCache + fileName, function(exists) {
            if (exists) {
                fetchLocal()
            } else {
                fetchRemote(true)
            }
        })
        console.log('Contentful: Initial dump of data.')
    },
    update: function(req, res, next) {
        fetchRemote()
        res.end()
    },
    pluck: function(name) {
        console.log('Contentful: returning data: ' + name)
        return data[name] || {}
    }
}

express.js

'use strict';

var fs = require('fs'),
    http = require('http'),
    https = require('https'),
    express = require('express'),
    bodyParser = require('body-parser'),
    methodOverride = require('method-override'),
    favicon = require('serve-favicon'),
    Contentful = require('./middlewares/contentful-cache').init()

module.exports = function() {

    // Initialize express app
    var app = express();

    // uncomment after placing your favicon in /public
    app.use(favicon('public/favicon/favicon.ico'));

    // Set views path and view engine
    app.engine('server.view.html', 'swig');
    app.set('view engine', 'server.view.html');
    app.set('views', './app/views');

    // Request body parsing middleware should be above methodOverride
    app.use(bodyParser.urlencoded({
        limit: '50mb',
        extended: true
    }));
    app.use(bodyParser.json());
    app.use(methodOverride());

    // Init the routes
    require('./routes')(app);

    //500
    app.use(function(err, req, res, next) {
        if (!err) return next();
        console.error(err.stack);
        res.status(500).render('500', {
            error: (process.env.NODE_ENV === 'development') ? err.stack : err.message
        });
    });

    //404
    app.use(function(req, res) {
        res.status(404).render('404', {
            url: req.originalUrl,
            error: 'Not Found'
        });
    });

    return app;
};

routes.js

'use strict';

var _ = require('lodash'),
    Contentful = require('./middlewares/contentful-cache'),
    marked = require('marked');


module.exports = function(app) {

    app.all('/contentful-incoming', Contentful.update);

    app.get('/contentful', function(req, res) {
        res.render('contentful',{
            localtitle: 'Contentful - ',
            data: Contentful.pluck('entries')
        });
    });

    app.get('/contentful/:index', function(req, res) {
        res.render('contentful-article',{
            localtitle: 'Contentful - ',
            data: Contentful.pluck('entries'),
            index: req.params.index,
            marked: marked
        });
    });

};