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Reference error is not defined on application

When trying to submit data on a form, the webserver is giving me an error saying Reference error: Item is not defined, but based on my code, everything looks okay to me. Is there anything that stands out to you in my code that might cause this?
I was playing around with the Const, but I'm not sure if that's where the problem lies.
Here's my Javascript file:
const express = require('express');
const app = express();
const bodyParser = require('body-parser');
const mongoose = require('mongoose');
//specify where to find the schema
const Items = require('./models/item')
// connect and display the status
mongoose.connect('mongodb://localhost:27017/items', { useNewUrlParser: true, useUnifiedTopology: true })
.then(() => { console.log("connected"); })
.catch(() => { console.log("error connecting"); });
// use the following code on any request that matches the specified mount path
app.use((req, res, next) => {
console.log('This line is always called');
res.setHeader('Access-Control-Allow-Origin', '*'); //can connect from any host
res.setHeader('Access-Control-Allow-Methods', 'GET, POST, PUT, OPTIONS'); //allowable methods
res.setHeader('Access-Control-Allow-Headers', 'Origin, Content-Type, Accept');
next();
});
app.get('/items', (req, res, next) => {
//call mongoose method find (MongoDB db.Items.find())
Items.find()
//if data is returned, send data as a response
.then(data => res.status(200).json(data))
//if error, send internal server error
.catch(err => {
console.log('Error: ${err}');
res.status(500).json(err);
});
});
// parse application/x-www-form-urlencoded
app.use(bodyParser.urlencoded({ extended: false }))
// parse application/json
app.use(bodyParser.json())
// serve incoming post requests to /items
app.post('/items', (req, res, next) => {
// create a new item variable and save request’s fields
const Items = new items ({
itemName: req.body.itemName,
servings: req.body.servings
});
//send the document to the database
Items.save()
//in case of success
.then(() => { console.log('Success');})
//if error
.catch(err => {console.log('Error:' + err);});
});
//to use this middleware in other parts of the application
module.exports=app;

app.post('/items', (req, res, next) => {
// Items already defined
const items = new Items({
itemName: req.body.itemName,
servings: req.body.servings
});
items.save()
//in case of success
.then(() => { console.log('Success');})
//if error
.catch(err => {console.log('Error:' + err);});
});
Items constant is already declared, and you trying to re-declare it

Fetch method put with React.js and Node server

I want to update my data in my MySQL database. I have React front-end and I'm using node server as back-end. I am getting nothing with body when I try to update data with fetch put method. Why is that?
Why does "body" in fetch method with JSON.stringify(req.body) give me an empty object server-side?
React code(button click event):
handlePrioDown(a) {
sessionStorage["id"] = a["id"];
sessionStorage["priority"] = a["priority"];
fetch('http://localhost:3001/TeacherPri/'+a["id"], {
method: 'PUT',
body: JSON.stringify({priority: a["priority"]+1})
})
}
Node (server.js):
//CORS middleware
var allowCrossDomain = function(req, res, next) {
res.header('Access-Control-Allow-Origin', '*');
res.header('Access-Control-Allow-Methods', 'GET,PUT,POST,DELETE');
res.header('Access-Control-Allow-Headers', 'Content-Type');
next();
}
app.use( bodyParser.json())
app.use(bodyParser.urlencoded({
extended: true
}))
app.use(allowCrossDomain)
app.use(express.json())
app.route("/TeacherPri/:id")
.put(controller.changePriority)
Node (controller.js):
changePriority: (req ,res) => {
let v = req.body;
let key = req.params.id;
console.log(JSON.stringify(v) + " ::::: id="+key)
CONN.query('UPDATE teacher SET priority=? WHERE id=?', [v.priority, key],
(err, results, fields) => {
if(err) {
console.log(err)
res.json(err)
} else {
console.log("Done")
res.statusCode = 204
res.send();
}
})
}
I'm excpecting that I get something like { priority: 4 } as req.body object on server side. I get empty object atm.

Axios data is breaking the request

I have an express API and a ReactJs front-end. I try to make a POST call from my front-end directly to the local API.
For this I'm using axios.
The request is working fine when I set the parameters directly inside the query string but is always getting on timeout if I try to add the parameters through the data attribute of the axios.post() method.
Working
axios.post(`http://localhost:5001/site/authenticate?username=demo&password=demo`)
Not working
const payload = {
"username":"mh",
"password":"mh"
}
axios.post(`http://localhost:5001/site/authenticate`, payload)
My express server:
const express = require('express');
const bodyParser = require('body-parser');
const morgan = require('morgan');
const jwt = require('jsonwebtoken'); // used to create, sign, and verify tokens
var cors = require('cors');
const app = express();
const port = process.env.API_PORT || 5001;
app.use(cors());
app.set('secret', process.env.API_SECRET);
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());
app.use(morgan('dev'));
app.use((req, res, next) => {
let data = '';
req.setEncoding('utf8');
req.on('data', (chunk) => {
data += chunk;
});
req.on('end', () => {
req.rawBody = data;
next();
});
});
// Allow CORS
app.use(function(req, res, next) {
res.header("Access-Control-Allow-Origin", "*");
res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
next();
});
// SITE ROUTES -------------------
const siteRoutes = express.Router();
siteRoutes.post('/authenticate', function(req, res) {
console.log('auth');
getDocument(usersBucket, req.query.username)
.then((doc) => {
console.log("Authentification... TODO");
// return the information including token as JSON
res.json({
success: true,
status: 200,
token: token
});
})
.catch(() => {
res.status(401).json({ success: false, message: 'Authentification failed. User not found.' });
});
});
// route middleware to verify a token
siteRoutes.use(function(req, res, next) {
const token = req.body.token || req.query.token || req.headers['x-access-token'];
if (token) {
// verifies secret and checks exp
jwt.verify(token, app.get('secret'), function(err, decoded) {
if (err) {
return res.json({ success: false, message: 'Failed to authenticate token.', status: 401 });
} else {
req.decoded = decoded;
next();
}
});
} else {
return res.status(403).send({
success: false,
message: 'No token provided.'
});
}
});
siteRoutes.get('/', function(req, res) {
res.json({ message: 'Welcome!' });
});
app.use('/site', siteRoutes);
app.listen(port, () => {
logger.log(`Express server listening on port ${port}`);
});
Any idea? Thanks.
Update
I replaced my route just to see if I got in or not (without worrying about parameters):
siteRoutes.post('/authenticate', function(req, res) {
console.log("go in");
res.json({
success: true,
status: 200,
});
});
But my console.log is not showing hen I use the payload (it is when I do not).

You should access the payload data via request.body, not the request.query:
// SITE ROUTES -------------------
const siteRoutes = express.Router();
siteRoutes.post('/authenticate', function(req, res) {
console.log('auth');
getDocument(usersBucket, req.body.username) // <------- HERE
.then((doc) => {
console.log("Authentification... TODO");
// return the information including token as JSON
res.json({
success: true,
status: 200,
token: token
});
})
.catch(() => {
res.status(401).json({ success: false, message: 'Authentification failed. User not found.' });
});
});
request.query are the parameters passed in the URL, like:
protocol://hostname:port/path/to.route?query_param_0=value_0&query_param_1=value_1
on your express endpoint request.query will be:
{
query_param_0: value_0,
query_param_1: value_1
}
while sending the payload, with the second argument in axios.post(url, payload):
axios.post('/user', {
firstName: 'Fred',
lastName: 'Flintstone'
})
on your express endpoint request.body will be:
{
firstName: 'Fred',
lastName: 'Flintstone'
}
when you use app.use(bodyParser.json()); (and you do).

You are using “getDocument(usersBucket, req.query.username)”
This means you express route is expecting username as a request param. That’s why it’s working when you use “?username=xx”
Instead try to get it from json body of request.
“req.body.username”
Also you should consider validating the request body or param as required.

Capturing response body in Express Middleware

I am trying to write a small API logger as an Express middleware. The logger collects various pieces of information from the req and res, then saves a JSON file to disk that can be read later.
This is my current function to store the logs.
function store(req, res, next) {
init();
const log = {
request_url: req.hostname,
request_body: req.body,
request_method: req.method,
request_headers: req.headers,
api_endpoint: req.baseUrl,
timestamp: moment().format('x')
};
res.on('finish', () => {
log.response_body = res.body;
log.response_status = res.statusCode;
global.enoch_logs.push(log);
fs.writeFile(`./logs/${ moment().format('x') }.json`, JSON.stringify(log), (err) => (err) ? console.log(err) : null);
});
next();
}
The problem is that res.body is always empty. I have tried a few different methods to capture the response body but nothing seems to work.
Where am I going wrong?

How can i store token value into my local javascript file

Hi am a beginner to Nodejs i have used passportjs token based authentication if the user logins it provides a token for each user i want to perform some operations based for the users who has token values for example if the user want to see the list of registered users they can view it if he has the token value. Now it provides me the token value perfectly in Postman but i don't know how to store it in a variable and call it via FRONT-END. I want do it via Front End(If he clicks the get users button) it should display the list of users.I have done that in POSTMAN it works finely i don't have an idea how to do it via frontend.
My user Code(Login/Logout)
var express = require('express');
var router = express.Router();
var User = require('../models/user');
var passport = require('passport');
var Verify = require('./verify');
/* GET users listing. */
router.route('/')
.get(Verify.verifyOrdinaryUser, function(req, res, next) {
User.find({}, function (err, users) {
if (err) throw err;
res.json(users);
});
});
router.post('/register', function(req, res, next) {
User.register(new User({ username : req.body.username }),req.body.password, function(err, user) {
if (err) {
return res.status(500).json({err: err});
}
user.save(function(err,user) {
passport.authenticate('local')(req, res, function () {
return res.status(200).json({status: 'Registration Successful!'});
});
});
});
});
router.post('/login', function(req, res, next) {
passport.authenticate('local', function(err, user, info) {
if (err) {
return next(err);
}
if (!user) {
return res.status(401).json({
err: info
});
}
req.logIn(user, function(err) {
if (err) {
return res.status(500).json({
err: 'Could not log in user'
});
}
var token = Verify.getToken(user);
res.status(200).json({
status: 'Login successful!',
success: true,
token: token
});
});
})(req,res,next);
});
router.get('/logout', function(req, res) {
req.logout();
res.status(200).json({
status: 'Bye!'
});
});
module.exports = router;
Main.js File. In this main.js file i want to send that token in this get method any idea?
$(".get-users-button").click(function() {
$.ajax({
method: "GET",
url: " http://localhost:3000/users"
})
.done(function(msg) {
console.log(msg);
template(msg);
});
});

When you get back a successful response from the POST to your /login endpoint, store the token on client-side (e.g., window.localStorage.setItem('<your-namespace>-user-token', <the token goes here>);)
Then, when user clicks the 'get-users-button', get the token out of storage (e.g., window.localStorage.getItem('<your-namespace>-user-token'); and store it in a variable if you want.
Then, on your request to get users, add your { 'x-access-token': <token variable goes here> } to your request headers.

As per the documentation for Passport:
If authentication succeeds, the next handler will be invoked and the req.user property will be set to the authenticated user.
Now if I'm understanding your question correctly, you want to pass the token value you obtain from:
var token = Verify.getToken(user)
to the view in which your front-end can do something with. You can pass variables to the view using the following middleware:
app.use((req, res, next) => {
res.locals.token = Verify.getToken(req.user)
next()
}
See the documentation for res.locals for more details.
Example usage:
app.js
const express = require('express')
const app = express()
app.set('view engine', 'pug')
app.use((req, res, next) => {
res.locals.text = 'asdf'
res.locals.token = 'abc'
next()
})
app.get('/', (req, res) => {
res.render('index')
})
app.listen(3000, () => {
console.log('listening on 3000')
})
views/index.pug
doctype html
html
head
title= title
body
h1= text
script.
console.log('#{token}')