We need an endpoint to get user information by some identifier. To create the endpoint we need, follow these steps:

1. Define the route:

routerAuth.get('/users/:id', User.show);

2. Define the show method inside the user controller, server/api/user.js:

show: (req, res) => {
    Model.users
      .getBy(req.params.id)
      .then(user => handleSuccess(res, { user: user.toJson() }))
      .catch(errors => handleFailure(res, { errors, message: errors.message }));
  },

3. Define the getBy method inside the user model:

  Schema.statics.getBy = function(id) {
    return new Promise((resolve, reject) => {
      try {
        this.findOne({ _id: id })
          .then(user => resolve(user))
          .catch(error => reject(error));
      } catch (e) {
        reject(e);
      }
    });
  };

As part of the exercise, we leave it up to you to test these endpoints.