app.js

const express = require('express');
const path = require('path');
const favicon = require('serve-favicon');
const session = require('express-session');
const chalk = require('chalk');
const dotenv = require('dotenv');
const MongoStore = require('connect-mongo')(session);
const flash = require('express-flash');
const mongoose = require('mongoose');
const passport = require('passport');
const expressValidator = require('express-validator');
const logger = require('morgan');
const bodyParser = require('body-parser');

/**
 * 从.env.example文件当中载入环境诸如API和passwords等环境参数
 */
dotenv.load({ path: '.env.example' });

/**
 * Controllers (route handlers).
 */
const homeController = require('./controllers/home');
const userController = require('./controllers/user');
const articleController = require('./controllers/article');

/**
 * API keys and Passport configuration. 
 * API以及Passport配置
 */
const passportConfig = require('./config/passport');

const app = express();

/**
 * Connect to MongoDB.
 * 连接MongoDB
 */
mongoose.Promise = global.Promise;
mongoose.connect(process.env.MONGODB_URI || process.env.MONGOLAB_URI);
mongoose.connection.on('error', (err) => {
  console.error(err);
  console.log('%s MongoDB connection error. Please make sure MongoDB is running.', chalk.red('✗'));
  process.exit();
});

// view engine setup
app.set('port', process.env.PORT || 3030);
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'pug');

app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));
app.use(expressValidator());

app.use(session({
  resave: true,
  saveUninitialized: true,
  secret: process.env.SESSION_SECRET,
  store: new MongoStore({
    url: process.env.MONGODB_URI || process.env.MONGOLAB_URI,
    autoReconnect: true,
    clear_interval: 3600
  })
}));
app.use(passport.initialize());
app.use(passport.session());
app.use(flash());

app.use((req, res, next) => {
  res.locals.user = req.user;
  next();
});
app.use((req, res, next) => {
  // After successful login, redirect back to the intended page
  // 成功登录之后，重定向到目标页面
  if (!req.user &&
    req.path !== '/login' &&
    req.path !== '/signup' &&
    !req.path.match(/^\/auth/) &&
    !req.path.match(/\./)) {
    req.session.returnTo = req.path;
  } else if (req.user &&
    req.path == '/account') {
    req.session.returnTo = req.path;
  }
  next();
});
app.use(express.static(path.join(__dirname, 'public'), { maxAge: 31557600000 }));

app.get('/', homeController.index);
app.get('/login', userController.getLogin);
app.post('/login', userController.postLogin);
app.get('/logout', userController.logout);
app.get('/signup', userController.getSignup);
app.post('/signup', userController.postSignup);
app.get('/post',articleController.index);
app.post('/post',articleController.postArticle);
app.get('/account', passportConfig.isAuthenticated, userController.getAccount);
app.post('/account/profile', passportConfig.isAuthenticated, userController.postUpdateProfile);
app.post('/account/delete', passportConfig.isAuthenticated, userController.postDeleteAccount);

app.get('/auth/github', passport.authenticate('github'));
app.get('/auth/github/callback', passport.authenticate('github', { failureRedirect: '/login' }), (req, res) => {
  res.redirect(req.session.returnTo || '/');
});

/**
 * Start Express server.
 * 开启Express服务器
 */
app.listen(app.get('port'), () => {
  console.log('%s App is running at http://localhost:%d in %s mode', chalk.green('✓'), app.get('port'), app.get('env'));

  console.log('  Press CTRL-C to stop\n');
});

module.exports = app;