Develop Reference

rendering username or id in the url with express routing

I have read some documentation on express routing and I am trying to render the logged in user's username or identification in the url. I need help getting the routing hit in my server.js to render the pages even before authentication. Where am I messing up?
Routing (profile.js)
const express = require("express");
var router = express.Router();
const User = require("../models/user");
const passport = require("passport");
const multer = require("multer");
// Profile Avatar
const upload = multer({ dest: "upload" });
// ACCOUNT ROUTES
router
.route("/profile/:id")
.get(function (req, res) {
if (req.isAuthenticated()) {
let dateObj = req.user.createdAt;
let createdDate = dateObj.toString().slice(4, 16);
let navbarLoggedIn = "partials/loggedIn-navbar.ejs";
let id = req.params.username;
console.log(id + "\n");
res.render(
"profile",
{ id: req.params.id },
{
currentUser: req.user.username,
currentCompany: req.user.company,
currentLocation: req.user.location,
currentPosition: req.user.position,
memberStatus: createdDate,
navbar: navbarLoggedIn,
}
);
} else {
res.redirect("login");
}
})
.post(function (req, res) {});
module.exports = router;
server.js
require("dotenv").config();
const express = require("express");
const session = require("express-session");
const passport = require("passport");
const path = require("path");
const ejs = require("ejs");
const logger = require("morgan");
const main = require("./routes/main");
const about = require("./routes/about");
const contact = require("./routes/contact");
const profile = require("./routes/profile");
const pricing = require("./routes/pricing");
const help = require("./routes/help");
const login = require("./routes/login");
const signup = require("./routes/signup");
const forgot_password = require("./routes/forgot-password");
const User = require("./models/user");
const multer = require("multer");
// PORT
const port = 8080;
const app = express();
// COOKIES AND SESSION
app.use(
session({
secret: process.env.SECRET,
resave: false,
saveUninitialized: true,
})
);
app.use(passport.initialize());
app.use(passport.session());
// DATABASE
require("./config/database.js");
// PASSPORT AUTHENTICATION
require("./config/passport.js");
// MIDDLEWARE
app.use(logger("dev"));
app.use(express.urlencoded({ extended: true }));
app.use(express.json());
app.use("/public", express.static(path.join(__dirname + "/public")));
app.set("view engine", "ejs");
app.set("view cache", false);
// ROUTES
app.use("/", main);
app.use("/about", about);
app.use("/contact", contact);
app.use("/pricing", pricing);
app.use("/profile/:id", profile, (req, res, next) => {
next();
});
app.use("/help", help);
app.use("/login", login);
app.use("/signup", signup);
app.use("/forgot-password", forgot_password);
// Logout
app.get("/logout", function (req, res) {
res.clearCookie("connect.sid");
res.redirect("/");
});
app.listen(port, (err, done) => {
if (!err) {
console.log({ message: "success!" });
} else {
return err;
}
});
And here is my file structure.file structure.
views strucutre

When you define the profile router in your main server file, instead of defining one specific route, define a short prefix. In your case you'll use /profile. Then in your router simply define the rest of the route (/:id).
Example:
Server:
app.use("/profile", profile, (req, res, next) => {
next();
});
Router:
router
.route("/:id")
.get(function (req, res) {
if (req.isAuthenticated()) {
let dateObj = req.user.createdAt;
let createdDate = dateObj.toString().slice(4, 16);
let navbarLoggedIn = "partials/loggedIn-navbar.ejs";
let id = req.params.username;
console.log(id + "\n");
res.render(
"profile",
{
id: req.params.id
},
{
currentUser: req.user.username,
currentCompany: req.user.company,
currentLocation: req.user.location,
currentPosition: req.user.position,
memberStatus: createdDate,
navbar: navbarLoggedIn,
}
);
} else {
res.redirect("login");
}
});

TypeError: Assignment to constant variable

Please help me solve the error. I have attached my index.js code routes.js code and db.js code and the error description.
I've been trying hard to solve the error.
index.js
const express = require('express');
const app = express();
const routes = require('./routes');
const path = require('path');
const fileUpload = require('express-fileupload');
const bodyParser = require('body-parser');
const session = require('express-session');
const auth = require('./routes/auth');
const {
con,
sessionStore
} = require('./config/db');
const fs = require('fs');
require('dotenv').config({
path: path.join(__dirname, '.env')
});
const port = process.env.PORT || 3000;
// parse application/json
app.use(bodyParser.json())
// parse application/x-www-form-urlencoded
app.use(bodyParser.urlencoded({
extended: false
}));
//static files
app.use(express.static('public'))
app.use('/css' , express.static(__dirname + 'public/css'))
app.use('/imgs' , express.static(__dirname + 'public/imgs'))
var sess = {
secret: 'keyboard cat',
store: sessionStore,
cookie: {
httpOnly: false,
},
resave: false,
saveUninitialized: false
}
app.use(session(sess));
app.use(fileUpload());
//set views
app.set('view engine' , 'ejs');
app.set('views', path.join(__dirname, 'views'))
//
app.use(require('connect-flash')());
app.use((req, res, next) => {
res.locals.messages = require('express-messages')(req, res);
next();
});
app.get('/', (req,res) =>{
res.render('index22')
})
app.get('/login', (req, res) => {
res.render('login');
});
let s;
const loginRequired = (req, res, next) => {
if (req.session.username) {
s = req.session;
next();
} else {
res.redirect('/auth/login');
}
}
// app.get('/new', (req, res) => {
// res.render('new');
// });
// app.get('/show', (req, res) => {
// res.render('show');
// });
// app.get('/', loginRequired, (req, res) => {
// res.redirect('/new');
// });
// app.get('/', loginRequired, (req, res) => {
// res.redirect('/show');
// });
app.get('/new', loginRequired, routes.new);//call for main index page
app.post('/new', loginRequired, routes.new);//call for signup post
app.get('/show', loginRequired, routes.show);
app.use('/auth', auth);
app.listen(port, () => console.log(`listening on http://${process.env.HOST}:${port}`));
routes.js
const {
con,
sessionStore
} = require('./config/db');
exports.new = function(req, res){
message = '';
if(req.method == "POST"){
const post = req.body;
const username= post.username;
const title= post.title;
const state= post.state;
const category= post.category;
const description= post.description;
if (!req.files)
return res.status(400).send('No files were uploaded.');
const file = req.files.uploads;
const img_name=file.name;
if(file.mimetype == "image/jpeg" ||file.mimetype == "image/png"||file.mimetype == "image/gif" ){
file.mv('public/imgs/uploads/'+file.name, function(err) {
if (err)
return res.status(500).send(err);
const sql = "INSERT INTO `nt_data`(`username`,`title`,`state`,`category`, `img_name` ,`description`) VALUES ('" + username + "','" + title + "','" + state + "','" + category + "','" + image + "','" + description + "')";
const query = con.query(sql, function(err, result) {
res.redirect('show/'+result.insertUsername);
});
});
} else {
message = "This format is not allowed , please upload file with '.png','.gif','.jpg'";
res.render('new.ejs',{message: message});
}
} else {
res.render('new');
}
};
exports.show = function(req, res){
const message = '';
const username = req.params.username;
const sql="SELECT * FROM `nt_data` WHERE `username`='"+username+"'";
con.query(sql, function(err, result){
if(result.length <= 0)
message = "show not found!";
res.render('show.ejs',{data:result, message: message});
});
};
db.js
const mysql = require('mysql');
const path = require('path');
const session = require('express-session');
const MySQLStore = require('express-mysql-session')(session);
require('dotenv').config({ path: path.join(__dirname, '../.env') });
// config for your database
const con = mysql.createConnection({
user: process.env.DB_USER,
password: process.env.DB_PASSWORD,
server: process.env.DB_HOST,
database: process.env.DB_NAME,
port: parseInt(process.env.DB_PORT)
});
var sessionStore = new MySQLStore({}/* session store options */, con);
// connect to your database
con.connect((err) => {
if (err) throw err;
console.log("Connected to database");
});
module.exports = { con, sessionStore };
Description of the error:
C:\Users\hp\Desktop\Internship\Nt\node_modules\mysql\lib\protocol\Parser.js:437
throw err; // Rethrow non-MySQL errors
^
TypeError: Assignment to constant variable.
at Query.<anonymous> (C:\Users\hp\Desktop\Nt\routes.js:50:12)
at Query.<anonymous> (C:\Users\hp\Desktop\Nt\node_modules\mysql\lib\Connection.js:526:10)
at Query._callback (C:\Users\hp\Desktop\Nt\node_modules\mysql\lib\Connection.js:488:16)
at Query.Sequence.end (C:\Users\hp\Desktop\Nt\node_modules\mysql\lib\protocol\sequences\Sequence.js:83:24)
at Query._handleFinalResultPacket (C:\Users\hp\Desktop\Nt\node_modules\mysql\lib\protocol\sequences\Query.js:149:8)
at Query.EofPacket (C:\Users\hp\Desktop\\Nt\node_modules\mysql\lib\protocol\sequences\Query.js:133:8)
at Protocol._parsePacket (C:\Users\hp\Desktop\Nt\node_modules\mysql\lib\protocol\Protocol.js:291:23)
at Parser._parsePacket (C:\Users\hp\Desktop\Nt\node_modules\mysql\lib\protocol\Parser.js:433:10)
at Parser.write (C:\Users\hp\Desktop\Nt\node_modules\mysql\lib\protocol\Parser.js:43:10)
at Protocol.write (C:\Users\hp\Desktop\Nt\node_modules\mysql\lib\protocol\Protocol.js:38:16)
I guess mainly the error is in the routes.js file
Any help will be highly appreciated.
Thank you

Just update const to let in the show function:
exports.show = function(req, res){
let message = '';
const username = req.params.username;
const sql="SELECT * FROM `nt_data` WHERE `username`='"+username+"'";
con.query(sql, function(err, result){
if(result.length <= 0)
message = "show not found!";
res.render('show.ejs',{data:result, message: message});
});
};
Or given you don't really need to reassign it, just create the variable inside the body if the if statement:
exports.show = function(req, res){
const username = req.params.username;
const sql="SELECT * FROM `nt_data` WHERE `username`='"+username+"'";
con.query(sql, function(err, result){
if(result.length <= 0)
const message = "show not found!";
res.render('show.ejs',{data:result, message: message});
});
};
Hopefully that helps!

Once you declare a const you cannot reassign it. Check out the MDN docs for more information.
This won't work
const message = ""
message = "show not found!";
This will
let message = ""
message = "show not found!"

I had a similar issue with connect-mongo. Double-check with the express-mysql-session latest docs and check if you're importing packages you already required accidentally. Sometimes, ``IDEs like Visual Studio Code does this. It was importing const{express-session} by the IDE and assigning it to mongostore.

No data is being inserted into my database

I'm trying to insert data into my database using a POST request. Data is being sent to my server but when I try to INSERT it into my database it doesn't do anything. Even the console.log in the query is being sent to the console. The req.file is showing the right info as well.
var express = require('express');
var app = express();
var multer = require('multer');
var cors = require('cors');
var bodyParser = require('body-parser');
const port = 8000;
const Pool = require('pg').Pool
const pool = new Pool({
user: 'me',
host: 'localhost',
database: 'api',
password: 'password',
port: 5432,
})
app.use(cors())
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
var storage = multer.diskStorage({
destination: function (req, file, cb) {
cb(null, 'public')
},
filename: function (req, file, cb) {
cb(null, Date.now() + '-' +file.originalname)
}
})
var upload = multer({ storage: storage });
app.post('/upload', upload.single('file'), function(req, res) {
message: "Error! in image upload."
if (!req.file) {
console.log("No file recieved");
message = "Error! in image upload."
console.log("status: danger");
} else {
console.log('file recieved');
console.log(req.file);
var query = pool.query('INSERT INTO file (name, type, size) VALUES ($1, $2, $3)', [req.file.filename , req.file.mimetype, req.file.size], function(err, result) {
console.log('inserted data')
});
message = "Successfully uploaded";
console.log("status: success");
}
})
app.listen(port, () => {
console.log(`App running on port ${port}.`)
})

Redirect after Post method , expressjs

I'm learing ExpressJS, and so far I did the user registration part but when I want to redirect to the home page after finishing the registration, it's not
showing the json after clicking on Submit button. May I know how I could do it.
Database
var mysql = require('mysql');
var con = mysql.createConnection({
host: "localhost",
user: "root",
password: "",
database:'reciepeapp'
});
module.exports = con
the ORM
const con = require('./db')
The ORM
const orm = {
insertOne: function (values, cb) {
const sqlQuery = "INSERT INTO authentication(username,password) VALUES ?";
con.query(sqlQuery, [values],function (err, data) {
if (err) {
console.log(err)
cb(err, null);
} else {
cb(null, data);
}
});
},
}
module.exports = orm;
The route.js
Here I insert the data obtained during registration (register index html) into a database. It's working well but I want to redirect to home page.
const express = require('express');
const app = express()
const router = express.Router()
const bcrypt = require('bcrypt');
bodyParser = require('body-parser');
app.use(bodyParser.urlencoded({ extended: true }));
const orm = require('../models/orm')
router.get('/',(req,res)=>
res.render('home')
)
router.get('/login',(req,res)=>
res.render('login')
)
router.get('/register',(req,res)=>
res.render('register')
)
router.post("/register", async (req, res) =>{
try {
const hashedPassword = await bcrypt.hash(req.body.password,10)
values = { username: req.body.name,
password:hashedPassword }
orm.insertOne(values, function(error) {
if (error) {
return res.status(401).json({
message: 'Not able to add'
});
}
values = { username: values.username,
password: values.password }
orm.insertOne(values, function(error) {
if (error) {
return res.status(401).json({
message: 'Not able to add'
});
}
**return res.send({
username: values.username,
password: values.password
});**
});
});
}
catch {
}
});
module.exports = router
const express = require('express');
const app = express()
const bodyParser = require("body-parser");
const indexRouter = require('./routes/route')
const con = require('./models/db')
con.connect(function(err) {
if (err) {
return console.error('error: ' + err.message);
}
console.log('Connected to the MySQL server.');
});
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());
var exphbs = require('express-handlebars');
console.log(__dirname)
app.use('/',express.static(__dirname + '/public'));
app.engine('handlebars', exphbs());
app.set('view engine', 'handlebars');
app.use('/',indexRouter)
const PORT = 5000;
app.listen(PORT,()=>console.log('it started on 5000'))

To do this you need to use express's redirect method.
Example:
var express = require('express');
var app = express();
const urlBase = 'localhost:3000/'
app.post('/', function(req, res) {
const redirectUrl = "index.html"
res.redirect(urlBase + redirectUrl);
});
app.listen(3000, function () {
console.log('Example app listening on port 3000!');
});
Docs: Express 4.x Docs

Random redirection

i have a Problem with my project. I want to make a little download system for pictures, so i made a router for /download/:filename. I have the pictures in /userdata/${userId}/ and if i request /download/ with a param like test it logs in my console, but if i use a param wich exists in the userdata folder like Download.jpg it redirects me back to the homepath of the user: /file/${userId} here is my code:
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');
const admin = require("./routes/admin");
import file from "./routes/file";
import download from "./routes/download";
const session = require("express-session");
var app = express();
app.set("trust proxy", 1);
app.use(session({
secret: "bla",
resave: false,
cookie: {
maxAge: 120000000
},
saveUninitialized: false
}));
function checkIfLoggedin(req,res,next){
if(!(req.originalUrl === "/") && !req.session.loggedIn){
res.redirect('/');
return;
}
next();
};
// 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(express.static(path.join(__dirname, 'public')));
app.use(checkIfLoggedin);
app.use('/', index);
app.use("/admin", admin);
app.use("/file", file);
app.use("/download", download);
// 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;
index.js router
var express = require('express');
var router = express.Router();
const bcrypt = require('bcrypt-nodejs');
var dbPassword;
import mysql from "mysql";
//
/* GET home page. */
router.get('/', function(req, res, next) {
if (req.session.user != undefined) {
res.redirect("/file/"+req.session.user.userId);
}
else{
res.render('index', {});
}
});
router.post('/', function(req,res,next) {
console.log("1");
const enteredUsername = req.body.username;
const enteredPassword = req.body.password;
const con = mysql.createConnection({
host: "localhost",
user: "user",
password: "pass",
database: "db"
});
con.query('SELECT * FROM users WHERE username = ?;', [`${enteredUsername}`], (error, results, fields) => {
if (results.length > 0) {
console.log("2");
console.log(error);
let dbPassword = results[0].password;
bcrypt.compare(enteredPassword, dbPassword, (err,response) => {
console.log(err);
console.log(response);
console.log("3");
if (response == true) {
req.session.user = {
userId: results[0].userId,
username: results[0].username,
isAdmin: results[0].isAdmin,
};
req.session.loggedIn = true;
console.log("file");
if (req.session.user.isAdmin) {
res.redirect("/admin");
}
else{
res.redirect("/file/" + req.session.user.userId);
}
}
else{
req.session.loggedIn = false;
console.log("false");
res.send("Falsches Passwort");
}
});
}
else{
res.send("Falsche Daten");
}
});
});
router.get("/logout", (req,res,next) => {
if (req.session.user.userId) {
req.session.destroy();
res.redirect("/");
}
});
module.exports = router;
file.js
import express from "express";
import fs from "fs";
const router = express.Router();
const userDataPath = "/srv/www/www.precode.tech/www/userdata/";
router.get("/:userId", (req,res,next) => {
//console.log(req.params.userId == req.session.user.userId);
if (req.params.userId == req.session.user.userId) {
const userDataFiles = fs.readdirSync(userDataPath+req.session.user.userId);
res.render("file", {files : userDataFiles, user: req.session.user});
}
else{
res.status(403).render("unauthorized");
}
//res.send(`${req.params.userId} ${req.session.user.userId}`);
});
/*router.get("/:userId/download/:filename", (req,res,next) => {
console.log(req.params.filename);
if (req.params.userId == req.session.user.userId) {
let filePath = `${__dirname}/../userdata/${req.session.user.userId}/`;
res.download(filePath, req.params.filename);
next();
};
});*/
export default router;
download.js
import express from "express";
const router = express.Router();
/*router.get("/", (req,res,next) => {
res.send("download");
});*/
router.get("/:filename", (req,res,next) =>{
console.log(req.params.filename);
});
export default router;
It would be very nice, if you have ideas or see the problem.
Thank you :)
EDIT: It should not redirect to the base path of the user, the get request on download should allways console.log the item

I did not find the flaw, but let's cleanup the code and fix middleware attaching sequence (at least I saw cookie parser attached after session middleware, I suspect only that part) and check.
But let's check my code review / cleanup.
Really hope it helps.
app.js:
const express = require('express');
const path = require('path');
//const favicon = require('serve-favicon');
const logger = require('morgan');
const cookieParser = require('cookie-parser');
const bodyParser = require('body-parser');
const session = require("express-session");
const mysql = require('mysql');
const db = mysql.createConnection({
host: "localhost",
user: "user",
password: "pass",
database: "db"
});
const app = express();
app.set("trust proxy", 1);
// set view engine and renderer
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');
// serve static files
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico'))); // no need for it since express static will serve all static files in public folder
app.use(express.static(path.join(__dirname, 'public')));
// connect morgan to profile requests
app.use(logger('dev'));
// parse cookies first
app.use(cookieParser());
// then handle session
app.use(session({
secret: "bla",
resave: false,
cookie: {
maxAge: 120000000
},
saveUninitialized: true
}));
// handle requests data
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use((req, res, next) => {
req.db = db; // attach db connection to request context
next();
});
// public routes that does not need auth check
app.use('/', require('./routes/index'));
const checkIfLoggedin = (req, res, next) => {
if (!req.session.loggedIn) {
return res.redirect('/');
}
res.locals.user = req.session.user;
next();
};
// internal routes that needs auth check
app.use(
'/admin',
checkIfLoggedin,
require('./routes/admin'));
app.use(
'/files',
checkIfLoggedin,
require('./routes/files'));
/* no need for this route, it's covered in files.js
app.use(
'/download',
checkIfLoggedin,
download);
*/
// catch 404 and forward to error handler
app.use((error, req, res, next) => {
if (error) return next(error);
const err = new Error('Not Found');
err.status = 404;
next(err);
});
// error handler
app.use((error, req, res, next) => {
// set locals, only providing error in development
res
.status(error.status || 500)
.render('error', {
message: error.message,
error: req.app.get('env') === 'development' ? error : {}
});
});
module.exports = app;
routes/index.js:
const express = require('express');
const router = express.Router();
const logger = require('winston');
const bcrypt = require('bcrypt-nodejs');
const _ = require('lodash'); // install it: npm i --save lodash
/* GET home page. */
router.get('/', (req, res) => {
if (_.get(req, 'session.user.userId')) {
return res.redirect("/files/" + req.session.user.userId);
}
res.render('index', {});
});
router.post('/auth', (req, res, next) => {
const {username, password} = req.body;
const db = req.db;
const query = 'SELECT * FROM users WHERE username = ? LIMIT 1';
const fields = [username];
db.query(
query,
fields,
(err, result) => {
if (err) {
logger.error(err);
const error = new Error('System fehler');
return next(error);
}
const user = _.get(result, '0');
if (!user) {
req.session.loggedIn = false;
const error = new Error('Benutzer nicht gefunden');
error.status = 403;
return next(error);
}
bcrypt.compare(password, user.password,
(err, isEqual) => {
if(err || !isEqual) {
if (err) logger.error('Error in password compare:', err);
const error = new Error('Passwort ungültig');
error.status = 403;
return next(error);
}
req.session.user = _.pick(user, ['id', 'userId', 'username', 'isAdmin']);
req.session.loggedIn = true;
if (user.isAdmin) {
return res.redirect("/admin");
}
res.redirect("/files/" + user.userId);
});
});
});
router.get("/logout", (req, res) => {
// simply destroy session and redirect,
// no need for session check
req.session.destroy();
res.redirect("/");
});
module.exports = router;
routes/files.js:
const express = require('express');
const router = express.Router();
const logger = require('winston');
const fs = require('fs');
const path = require('path');
const async = require('async');
const userDataPath = path.join(__dirname, '..', 'userdata');
// no need to check userId with session.user.userId
// since middleware attached in app.js will guard this route
// and redirect user to '/'
router.get('/:userId', (req, res, next) => {
if(req.params.userId != req.session.user.userId) {
const error = new Error("You cannot access other user's files");
error.status = 403;
return next(error);
}
const directory = path.join(userDataPath, req.params.userId);
logger.info('Reading directory:', directory);
fs.readdir(
directory,
(err, entries) => {
if (err) {
logger.error(err);
const error = new Error('System error');
return next(error);
}
const directories = [];
const files = [];
async.eachLimit(
entries, 10,
(entry, done) => {
fs.stat(path.join(dir, entry), (error, stat) => {
if (stat.isFile()) files.push(entry);
if (stat.isDirectory()) directories.push(entry);
done();
});
},
() => {
res.render("files", {
directories,
files
});
});
});
});
router.get('/:userId/download/:filename', (req, res, next) => {
if(req.params.userId != req.session.user.userId) {
const error = new Error("You cannot access other user's files");
error.status = 403;
return next(error);
}
res.download(path.join(userDataPath, req.params.userId, req.params.filename));
});
module.exports = router;
P.S. If it works behind nginx, apache and etc make sure userdata folder is not accessible publicly.