Node.js & Express routing with parameters

Question

I currently have 2 routes in node.js for an API I am building. They are:

app.get('/api/v1/user/:userid', function (req, res) {
    return res.status(200).json(GetUser());
});

and

app.get('/api/v1/user', function (req, res) {
    return res.status(400).json('UserId expected');
});

As you can see, both routes actually should be combined into one, for example:

app.get('/api/v1/user/:userid', function (req, res) {
    console.log('this should still show if :userid is not populated, but it does not');

    if(!req.params.userid)
        return res.status(400).json('UserId expected');

    return res.status(200).json(GetUser());
});

However, when I test the above endpoint with Postman without the :userid specified, I will get a timeout. Obviously if I supply an :userid, I get the corresponding user.

Also I have found that the console.log will never show up in the terminal when :userid isn't specified. This is my terminal output:

this should still show if :userid is not populated, but it does not
GET /api/v1/user/56a6861675774c1a046bf780 200 3.140 ms - 274
GET /api/v1/user/ - - ms - -

So all the above leads me to believe that because the :userid is undefined or null, that it is breaking the express middleware. Is that assumption correct and how do I overcome it?

Answer 1

The assumption is correct. The handler defined for /api/v1/user/:user_id cannot be used for /api/v1/user. As such, the route /api/v1/user/ will be unable to handle 'GET' requests.

You need to define different handlers for the different routes.

A solution would be to use Express router middleware to define your routes.

var router = express.Router();
router.route('/api/v1/user')
  .get(); // define handler for multiple resources here.

router.route('/api/v1/user/:user_id')
  .get(); // define handler for single resource here.

app.use('/', router);