ess.js | Extremely simple selectors

I try to finish a login function on my web application; however, when I enter the correct password and username already registered in my database, it always returns 404.

I want to use sessions to identify each unique user. And what I also want to know how to jump to a new webpage after login in successfully.

Here is my code in app.js:

I am trying to serve my react app from Nodejs, but I am getting a GET error which is odd because when I run npm start and run the react start script all works well, but once I use node.js it doesn't work. Also if I navigate to a route by typing it in or trying to navigate backward it throws an error. For example, when you first navigate to the homepage it takes you to a login page, and if I go to another page and then hit back it throws a GET error even though it worked beforehand.

Problem:

I am working on a chat application. When I send more than 9-10 requests, the browser slows down and eventually, it just hangs. On refreshing the page, everything is back to normal. I searched the socket.io documentation but couldn't get any solution regarding this matter.

Code:

Here is my Backend Express.JS code:

index.js

I'm working in a React app where I want to get data from an Express server. Getting this error on the browser's console:

GET http://localhost:3000/api/products 404 (Not Found)

under this error, it says:

My project structure looks like this:

I have been trying to install Angular but everytime this part:

@angular/cli@12.0.3 postinstall C:\Users\Marco\AppData\Roaming\npm\node_modules@angular\cli

node ./bin/postinstall/script.js

Seems to throw an error. I'm not sure if I need this to work or not so I'll leave the last couple lines of the log here.

I'm trying to send verification emails when someone fills a form on my website and I'm achieving this using nodemailer.

And my node.js code looks like this:

i am working on a project with a react.js FE, a Node/Express.js BE and a database. I am currently working on a function which trigger my delete Route in BE. But my function trigger with every load and onlick, but should only trigger onClick.

Here are code samples of my service and my FE component. I am new to react.js so help would be apprechiated.

hardwareService.js:

I want to analyze my Next.js build with source-map-explorer. Can someone please help me with the script?

With React (CRA), I use the following script: