How to use the express.json function in express

'use strict'

var express = require('express');
var request = require('request');
var Rubidium = require('../');

var app = express();
var rb = new Rubidium();

app.use(express.json());

// In this case, the body is the message and it includes a callback URL.
app.post('/add/:timestamp', function (req, res) {
	rb.add(parseInt(req.params.timestamp, 10), req.body);
	res.send(202);
});

// When the job is emitted, send it back to the callback URL.
rb.on('job', function (job) {
	var req;

	// Protect against 'Invalid Request' errors.
	try {
		req = request({ url: job.message.callbackUrl, method: 'POST', json: job.message });
	} catch (err) {
		console.error(err.stack || err.message);

//   useFindAndModify: false,
// };

// mongoose.connect(MONGO_URL, options);

const server = express();

server.use(cors({ origin: URL_APP, credentials: true }));

server.use(helmet());
server.use(compression());

// 11
// stripeWebHooks({ server });

server.use(express.json());

// 6
// const MongoStore = mongoSessionStore(session);
// const sessionOptions = {
//   name: SESSION_NAME,
//   secret: SESSION_SECRET,
//   store: new MongoStore({
//     mongooseConnection: mongoose.connection,
//     ttl: 14 * 24 * 60 * 60, // save session 14 days
//   }),
//   resave: false,
//   saveUninitialized: false,
//   cookie: {
//     httpOnly: true,
//     maxAge: 14 * 24 * 60 * 60 * 1000, // expires in 14 days
//     domain: COOKIE_DOMAIN,

//= =--- CAPTURE ENVIRONMENT VARIABLES
//= =---------------------------------------------------= =//
const {
  PORT = 7000,
  MONGO_DNS_SRV,
  MONGO_AUTH,
  MONGO_CLUSTER,
  MONGO_DB_NAME,
  MONGO_OPTIONS
} = process.env
//= =---------------------------------------------------= =//

//= =---------------------------------------------------= =//
//= =--- Use Express json parser
//= =---------------------------------------------------= =//
app.use(express.json())
//= =---------------------------------------------------= =//

//= =---------------------------------------------------= =//
// ---== HANDLE Homepage
//= =---------------------------------------------------= =//
app.get('/favicon.ico', (req, res) => res.status(204))
app.get('/', (request, response) => {
  response.send(`
  Welcome To Ratebook !<br>
  <a href="/users">Users</a><br>
  <a href="/books">Books</a>
  `)
})
//= =---------------------------------------------------= =//

//= =---------------------------------------------------= =//

const express = require('express')
const shell = require('shelljs')

const app = express()
app.use(express.json())
const port = 5709

// your-username ALL=NOPASSWD: /sbin/shutdown

app.post('/', (req, res) => {
  if (!req.body.command) return res.status(406).json({ response: "Missing params 'command'" })

  switch (req.body.command) {
    case 'off': {
      if (shell.exec('sudo shutdown -h +1 "Shutting down in 1 minute."').code !== 0) {
        return res.status(500).json({ response: "Can't run shutdown" })
      }
      return res.status(200).json({ response: 'Success' })
    }
    case 'reboot': {
      if (shell.exec('sudo shutdown -r +1 "Rebooting in 1 minute."').code !== 0) {

var indexRouter = require("./routes/index");
var usersRouter = require("./routes/users");
var testAPIRouter = require("./routes/testAPI");
var testDBRouter = require("./routes/testDB");
var submitRouter = require("./routes/submit");

var app = express();

// view engine setup
app.set("views", path.join(__dirname, "views"));
app.set("view engine", "jade");

app.use(cors());
app.use(logger("dev"));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, "public")));

app.use("/", indexRouter);
app.use("/users", usersRouter);
app.use("/testAPI", testAPIRouter);
app.use("/testDB", testDBRouter);
app.use("/submit", submitRouter);


// catch 404 and forward to error handler
app.use(function(req, res, next) {
    next(createError(404));
});

var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');
var Sequelize = require('sequelize');
require('dotenv').config()

var app = express();
var cors = require('cors');
// view engine setup
app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(cors());

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

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  next(createError(404));
});

// error handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

var express = require('express');
var http = require('http');
var path = require('path');
var app = express();
var accountStorage = require('./common/accountTableStorage');

var passport = require('passport');
var GoogleStrategy = require('passport-google-oauth').OAuth2Strategy;
var WindowsLiveStrategy = require('passport-windowslive');

// all environments
app.set('port', process.env.PORT || 3000);
//app.use(express.favicon());
app.use(express.logger('dev'));
app.use(express.json());
app.use(express.urlencoded());
app.use(express.methodOverride());
app.use(express.cookieParser());
app.use(express.bodyParser());
app.use(express.session({ secret: process.env.SESSION_SECRET }));
app.use(passport.initialize());
app.use(passport.session());
app.use(app.router);
app.use(express.static(path.join(__dirname, 'public')));

// development only
if ('development' == app.get('env')) {
    app.use(express.errorHandler());
}

//http://prestonpham.com/posts/google-oauth2/

require('dotenv').config()
const express = require('express')
const mongoose = require('mongoose')
const cookieParser = require('cookie-parser')
const cors = require('cors')
const helmet = require('helmet')
const projects = require('./routes/projects')
const users = require('./routes/users')

mongoose.connect(process.env.MONGO_URI)

const app = express()

// Middleware
app.use(express.json())
app.use(cookieParser())
app.use(helmet())

// Конфигурация CORS
app.use(
  cors({
    origin: process.env.CLIENT_URI,
    credentials: true
  })
)

// Маршрутизация
app.use('/api/projects', projects)
app.use('/api/users', users)

// Старт сервера

app.use(
  methodOverride("_method", {
    methods: ["POST", "GET"]
  })
);

app.use(layouts);
app.use(express.static("public"));
app.use(expressValidator());
app.use(
  express.urlencoded({
    extended: false
  })
);
app.use(express.json());

app.use(cookieParser("secretCuisine123"));
app.use(
  expressSession({
    secret: "secretCuisine123",
    cookie: {
      maxAge: 4000000
    },
    resave: false,
    saveUninitialized: false
  })
);
app.use(connectFlash());

app.use(passport.initialize());
app.use(passport.session());