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Express - get router.get to return json data attribute

I am new to javascript and would like to retrieve the json response from my express route get request. I can return the whole json but when i try to return a specific element i recieve an error (eg res.body.data). Here is my route file
route.js
var express = require('express');
var router = express.Router();
var request = require('request');
router.get('/', function(req, res, next) {
request({
uri: 'https://www.reddit.com/r/meme/new/.json'
}).pipe(res);
});
module.exports = router;
app.js
var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');
var cors = require("cors");
var indexRouter = require('./routes/index');
var usersRouter = require('./routes/users');
var testAPIRouter = require('./routes/testAPI');
var route = require('./routes/route');
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(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', indexRouter);
app.use('/users', usersRouter);
app.use('/testAPI', testAPIRouter);
app.use('/route', route);
// 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 : {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
module.exports = app;

You need to use body parser:
const app = express();
const bodyParser = require('body-parser');
app.use(bodyParser.urlencoded({ extended: false }));

Expressjs: throw new TypeError('Router.use() requires a middleware function but got a ' + gettype(fn))

I have been having some problems with trying to get my code to work. I have tried a couple things but and it says my error is in line 28: "app.use('/','indexRouter')" but I have no clue why. My index.js file and app.js file are copies of each other.
My app.js file:
let express = require('express')
let path = require('path')
let favicon = require('serve-favicon')
let cookieParser = require('cookie-parser')
let bodyParser = require('body-parser')
let logger = require('morgan')
//Starts an express app
let app = express()
//Gives access to routes
//You will seperate each route base on different activites and group them that way
let indexRouter = require('./routes/index')
let userRouter = require('./routes/users')
// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use(app.router);
routes.initialize(app);
app.use('/','indexRouter')
app.use('/users','userRouter')
// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
// 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 : {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
//ALlows www to get access to it
module.exports = app
index.js file:
var express = require('express');
var router = express.Router();
/* GET users listing. */
router.get('/', function(req, res, next) {
res.send('index js stuff');
});
module.exports = router;

indexRouter and userRouter should not be a string.
app.use('/', indexRouter)
app.use('/users', userRouter)

Node.js/Express req.body of POST is empty. POST request sent through Postman

Currently my code is this:
var express = require('express');
var router = express.Router();
var db = require('../helpers/db');
var data = {
"1": 127,
"2": 236,
"3": 348
}
router.get('/', function(req, res, next) {
res.send(data);
});
router.get('/:id', function(req, res, next) {
var key = req.params.id;
res.send({ [key]: data[key] });
});
router.post('/:id', function(req, res, next) {
var id = req.params.id;
console.log(id);
})
My goal is to be able to POST a value from Postman to API/values/:id, save that value under the id key and then save that "key": value pair in the data variable. Unfortunately, when I try to POST anything and then access it with req.body, I get {} or undefined.
app.js
var routes = require('./routes/');
var express = require('express');
var path = require('path');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var expressSession = require('express-session');
var app = express();
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');
// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(expressSession({
secret: 'secretText',
saveUninitialized: true,
resave: true
}))
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', routes.home);
app.use('/values', routes.values);
// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
// 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 : {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
module.exports = app;

To do so you need to have body-parser plugin of expressjs.
Install it using npm install --save body-parser and then use it like below
var bodyParser = require('body-parser');
express()
.use(bodyParser.urlencoded({
extended: true
}))
.use(bodyParser.json())

Node.js express router.post returns 404 not found

My express application seems to return 404 NOT FOUND whenever im using a post request method in my routes file. GET-requests are working fine and i can only see "GET" requests in the console aswell, even if im using a post request.
Is there some missing link between app.js and routes/index.js that might be causing this?
// routes/index.js
router.post('/foo', function (req, res, next) {
res.setHeader('Content-Type', 'application/json');
res.send('You sent: sdadad to Express');
})
// App.js
var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var index = require('./routes/index');
var app = express();
var cors = require('cors')
app.use(cors())
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');
// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', index);
// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
// 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 : {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
module.exports = app;
Result:
Not Found 404
Error: Not Found
at C:\Users\willow\Desktop\backend\app.js:29:13
at Layer.handle [as handle_request] (C:\Users\willow\Desktop\backend\node_modules\express\lib\router\layer.js:95:5)
at trim_prefix (C:\Users\willow\Desktop\backend\node_modules\express\lib\router\index.js:317:13)
at C:\Users\willow\Desktop\backend\node_modules\express\lib\router\index.js:284:7
at Function.process_params (C:\Users\willow\Desktop\backend\node_modules\express\lib\router\index.js:335:12)
at next (C:\Users\willow\Desktop\backend\node_modules\express\lib\router\index.js:275:10)
at C:\Users\willow\Desktop\backend\node_modules\express\lib\router\index.js:635:15
at next (C:\Users\willow\Desktop\backend\node_modules\express\lib\router\index.js:260:14)
at Function.handle (C:\Users\willow\Desktop\backend\node_modules\express\lib\router\index.js:174:3)
at router (C:\Users\willow\Desktop\backend\node_modules\express\lib\router\index.js:47:12)
at Layer.handle [as handle_request] (C:\Users\willow\Desktop\backend\node_modules\express\lib\router\layer.js:95:5)
at trim_prefix (C:\Users\willow\Desktop\backend\node_modules\express\lib\router\index.js:317:13)
at C:\Users\willow\Desktop\backend\node_modules\express\lib\router\index.js:284:7
at Function.process_params (C:\Users\willow\Desktop\backend\node_modules\express\lib\router\index.js:335:12)
at next (C:\Users\willow\Desktop\backend\node_modules\express\lib\router\index.js:275:10)
at SendStream.error (C:\Users\willow\Desktop\backend\node_modules\serve-static\index.js:121:7)

What you wanna do should look like this in practice:
// routes/index.js
module.exports = (express) => {
// Create express Router
var router = express.Router();
// add routes
router.route('/foo')
.post((req, res) => {
res.setHeader('Content-Type', 'application/json');
res.send('You sent: sdadad to Express');
});
return router;
}
// App.js
var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var routes = require('./routes')(express); // require routes at routes/index.js
var app = express();
var cors = require('cors')
app.use(cors())
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');
// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', routes);
// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
// 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 : {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
module.exports = app;

What I usually do is create a function that expects express as param like this
(routes/index.js)
module.exports = (express) => {
// Create express Router
var api = express.Router();
// add routes
api.route('/some_endpoint')
.post((req, res) => {
res.json({ message : 'some message' })
});
return api;
}
then I just import this file to my app.js
like this
(app.js)
// set api as a middleware
const api = require('./routes')(express);
app.use('/api/v1', api);
that way I hook up my api and my server.

Why is req.body always undefined for me

I cannot access any request parameters. e.g. req.body.username. for some reason req.body is always undefined. The endpoint is /youtube
app.js
var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var index = require('./routes/index');
var users = require('./routes/users');
var app = express();
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');
// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', index);
app.use('/users', users);
// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
// 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 : {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
module.exports = app;
server.js
var express = require("express");
var mysql = require('mysql');
var app = express();
var pool = mysql.createPool({
connectionLimit : 100, //important
host : 'localhost',
user : 'user',
password : 'pass',
database : 'db',
debug : false
});
var router = express.Router();// get an instance of the express Router
// middleware to use for all requests
router.use(function(req, res, next) {
// do logging
console.log('Incoming request');
next(); // make sure we go to the next routes and don't stop here
});
app.get("/",function(req,res){-
handle_database(req,res);
});
router.route('/youtube')
.post(function(req, res) {
console.log(req.body); // always undefined
})
.get(function(req, res) {
});
app.use('/api', router);
app.listen(3000);
console.log("Listening on port 3000....")

Add those 3 lines right below var app = express(); in server.js:
var bodyParser = require('body-parser');
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
Now your req.body will not be undefined.