Not getting expected results from included files in Nodejs - node.js

Question

I'm not getting expected results by including files in Nodejs. Here is my code:
Service Route File
const express = require('express');
const router = express.Router();
const path = require('path');
const config = require('../config');
const serviceAdapter = require('./serviceAdapter');
module.exports = (preRequestPath, serviceBaseUrl) => {
console.log("On server start", preRequestPath)
router.post('/*', (req, res) => {
console.log("On request", preRequestPath)
const axiosHttp = serviceAdapter(serviceBaseUrl);
axiosHttp.post(preRequestPath+req.path, req.body).then(resp => {
res.send(resp.data)
}).catch(err => {
res.status(404).sendFile(path.join(__dirname + '/../404.html'));
});
});
return router;
}
Main Server File
const express = require('express');
const userApiService = require('./routes/userService');
const userAdminService = require('./routes/userService');
app.use('/api/user_service/', userApiService("/api", config.userServiceUrl) );
app.use('/admin/user_service/', userAdminService("/admin", config.userServiceUrl) );
var server = app.listen(3000, function(){
console.log('Server listening on port 3000');
});
module.exports = server;
Expecting Console Result:
On server start /api
On server start /admin
On request /api (when hitting http://baseurl.com/api/<anything>)
On request /admin (when hitting http://baseurl.com/admin/<anything>)
But Getting Console Output as:
On server start /api
On server start /admin
On request /api (when hitting http://baseurl.com/api/<anything>)
On request /api (when hitting http://baseurl.com/admin/<anything>)
Both the time, returning /api path.
Can anyone tell me why is it happening and what's the solution?

Answer 1

You're creating only one router in userService.js (the first file). It's created once before the function so you really only end up with one router. The first time you require it the router gets created, but the second time you require it Node knows it was already loaded and it's not re-initialized. You should be creating a different router for each case like this:
const express = require('express');
// const router = express.Router(); <-- don't do it here
const path = require('path');
const config = require('../config');
const serviceAdapter = require('./serviceAdapter');
module.exports = (preRequestPath, serviceBaseUrl) => {
const router = express.Router(); // <--- create a new router for each case
console.log("On server start", preRequestPath)
router.post('/*', (req, res) => {
console.log("On request", preRequestPath)
const axiosHttp = serviceAdapter(serviceBaseUrl);
axiosHttp.post(preRequestPath+req.path, req.body).then(resp => {
res.send(resp.data)
}).catch(err => {
res.status(404).sendFile(path.join(__dirname + '/../404.html'));
});
});
return router;
}
Also in your main server file you only need to require it once. It's just a function to create the service so you don't need 2 different variables holding that function. So you can initialize both using the one function like this:
// const userApiService = require('./routes/userService');
// const userAdminService = require('./routes/userService');
const service = require('./routes/userService');
app.use('/api/user_service/', service("/api", config.userServiceUrl) );
app.use('/admin/user_service/', service("/admin", config.userServiceUrl) );