Node REST API : Need to combine multiple routes in an object - node.js

Question

I am building an application backend in TypeScript & NodeJS.
I have kept multiple routes logic in separate files(in single folder for each service) as :
> signup.ts // export { router as signupRouter };
> signin.ts // export { router as signinRouter };
> signout.ts // export { router as signoutRouter };
I need to do this for all the services in future.
I need to combine these routes so that I can specify them as a single entity in the index.ts file.
Something like:
import <object_that_combines_all> from './routes/<some_file_for_object>';
app.use('/api/users', require('./routes/users/<object_that_combines_all>'));
.
.
and so on
So that I don't have to mention each route explicitly in the index.ts file.

Answer 1

There is a simpler way using the router.use() method in which we can combine the individual endpoints.
Assuming your file structure looks something like this -
/src
/routes
/users
- signup.ts
- signin.ts
- signout.ts
index.ts (your main app entry point)
You can utilize the router.use() method provided by express.Router().
First, add a new index.ts file to the /routes/users folder to combine the multiple endpoints.
// /routes/users/index.ts
import * as express from 'express';
import { signupRouter } from './signupRouter';
import { signinRouter } from './signinRouter';
import { signoutRouter } from './signoutRouter';
const router = express.Router();
router.use(signupRouter);
router.use(signinRouter);
router.use(signoutRouter);
export {router as usersRouter};
Then in your main app entry point index.ts, do the following -
// /src/index.ts
import * as express from 'express';
import { usersRouter } from './routes/users/index.ts';
const PORT = process.env.PORT || 4000;
const app = express();
...
// Add your single entity entry point like this
app.use('/api/user', usersRouter);
...
app.listen(PORT, () => console.log(`Listening on port ${PORT}`)

Answer 2

To do that, you'll need to dynamically discover the filenames (readdir or similar) and use dynamic import to import them. Dynamic import (import()) returns a promise of the module namespace object for a module.
For instance, using the fs/promises version of readdir, something along these lines (off-the-cuff, some tweaking probably required):
import { readdir } from "fs/promises";
const directoryPath = "/path/to/the/files";
const rexIsRouterFile = /^.+\.ts$/i;
async function loadRoutes(app) {
const names = await readdir(directoryPath);
for (const name of names.filter(name => rexIsRouteFile.test(name))) {
const { router } of await import(`${directoryPath}/${name}`);
// ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^−−−−−−− dynamic import
app.use('/api/users', router);
}
}
Note that this assumes you have a TypeScript loader setup (for instance, as with ts-node). If you don't, you'll need to compile those TypeScript files to JavaScript before this runs, then change .ts to .js in rexIsRouterFile.