exception Handling In Express JS - node.js

Question

I am developing a rest api using express JS . I want to show several error such as route not found, data not found, validation error. I am using async await structure . I need to know how to manage several exception handling in Express JS . I search seveal website but not found exact way . Everywhere write to use nodeJS default exception . But i need it customize in REST API.
I need expert nodejs developer help . If anyone know best resource of express error handling please provide me link to learn this

Answer 1

1.Let for handling route not found error you can use the default route
app.all('/*', (req, res)=> res.status(404).send('Route Not Found'))
2.For handling response, you can set some predefined response in separate module and send all response from that module. Like
//response.js file
module.exports= {
ok : (res, data)=> res.status(200).send({data}),
error: (res, err)=> res.status(err.status).send({error})
}
3.For handling error you can make seperate error file where all error a set and create your error by those listed error. And you can do by try, catch
4.For validation, you can use middleware and or helper for handling validation.
5.Following are some node.js configuration link created by me, you can take reference from there
https://github.com/bapinmalakar/election-exitpoll-back (very simple, Github)
https://github.com/bapinmalakar/pt-backend (little complex, github)

Answer 2

You can log the error using middleware As below given example middleware we can catch the errors which are thrown across the application. Also, we can catch the promise rejections
const express = require("express");
const app = express();
app.use((err, req, res, next) => {
if (err) {
res.status(err.statusCode || 500).send(err);
console.error(err.stack);
next();
}
console.error(`Message :: ${err.message}
Url :: ${req.originalUrl}
Method :: ${req.method}
Ip :: ${req.ip}
Time :: ${(new Date()).toLocaleTimeString()}`);
});
For reference use this link. Click here