Express router bypasses middleware - node.js

Question

I am trying to create middleware to handle the response that are next()ed from the routes, but it bypasses route.use and throws 404
const router = require('express').Router();
const { errorResponse, successResponse, redirectResponse } = require('./test');
const errorResponse = (err, req, res, next) => {
next(Boom.notFound());
};
const successResponse = (err, req, res, next) => {
res.locals.res = {
data: {
hello: 'world'
}
};
next();
};
const redirectResponse = (err, req, res, next) => {
res.locals.res = {
meta: {
redirect: true
}
};
next();
};
module.exports = (app) => {
/**
* Test Routes
*/
router.get('/successTest', successResponse);
router.get('/errorTest', errorResponse);
router.get('/redirectTest', redirectResponse);
router
.use((err, req, res, next) => {
console.log('successHandler');
next();
})
.use((err, req, res, next) => {
console.log('redirectHandler');
next();
})
.use((err, req, res, next) => {
console.log('errorHandler');
res.status(200).json({});
});
// does not go to any of the middlewares and gives out 404
// from digging in i found that err param is not err but is req
app.use('/v1', router);
};
Thanks for helping

Answer 1

Take a look at Express.js Error-handling middleware documentation.
Basically it says that middleware with 4 arguments like
app.use(function (err, req, res, next) {
console.error(err.stack)
res.status(500).send('Something broke!')
})
interpreted as middleware to handle errors.
It means that it won't act like regular middleware.
For example:
app.get('/1',
(err, req, res, next) => {
// will not be outputted in console
console.log('got here');
next();
},
(req, res) => {
res.send('Hello World!');
});
app.get('/2',
(req, res, next) => {
console.log('got here');
next();
},
(req, res) => {
res.send('Hello World!');
});