Rest with Express.js nested router

You can nest routers by attaching them as middleware on an other router, with or without params.

You must pass {mergeParams: true} to the child router if you want to access the params from the parent router.

mergeParams was introduced in Express 4.5.0 (Jul 5 2014)

In this example the itemRouter gets attached to the userRouter on the /:userId/items route

This will result in following possible routes:

GET /user -> hello user
GET /user/5 -> hello user 5
GET /user/5/items -> hello items from user 5
GET /user/5/items/6 -> hello item 6 from user 5

var express = require('express');
var app = express();

var userRouter = express.Router();
// you need to set mergeParams: true on the router,
// if you want to access params from the parent router
var itemRouter = express.Router({mergeParams: true});

// you can nest routers by attaching them as middleware:
userRouter.use('/:userId/items', itemRouter);

userRouter.route("https://stackoverflow.com/")
    .get(function (req, res) {
        res.status(200)
            .send('hello users');
    });

userRouter.route('/:userId')
    .get(function (req, res) {
        res.status(200)
            .send('hello user ' + req.params.userId);
    });

itemRouter.route("https://stackoverflow.com/")
    .get(function (req, res) {
        res.status(200)
            .send('hello items from user ' + req.params.userId);
    });

itemRouter.route('/:itemId')
    .get(function (req, res) {
        res.status(200)
            .send('hello item ' + req.params.itemId + ' from user ' + req.params.userId);
    });

app.use('/user', userRouter);

app.listen(3003);

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