Express REST API with JWT and Routes - api

Question

I am trying to create an Express API with JWT authentication.
However, I was wondering how to best allow users to only access their own resources.
For example if there is a user with id 1 and each user has a list of books in the database:
The id is already part of the JWT Token but commonly there would be a request to something like /users/1/books to get all of the books belonging to user 1.
Would my routes typically still look like this and I would just check the id in the token is the same the request is made for, or is there any other/simpler way?
Thank you for your help!

Answer 1

You can define, some access rights permissions base on the user role or id.
Example: roles : {root, admin, staff}
Then, in your routes you can have some checking whether this user have the permission to access the functions or you can do in the controller level to check the access rights.
You need to define model relations between User, UserModel. In your case as I understand you need to have the relations between UserModel and BooksModels.
UserModel hasMany BooksModel
When you call findOne() to retrieve specific user's data, you can just define include: 'aliasModelName', to retrieve the users related book data.
With this way, you can only have 1endpoint users/:id to retrieve users data and book data. It depends on what you really want, you can also have an endpoint users/:id/books to get all books that belongs to this user.
Your model definition will then become
BooksModel belongsTo UserModel
If you use hasMany you can get all the results that you need in just one query.
Hope this helps!

Answer 2

When user sends the login credentials, you check database if the email exists, if yes then you check if the password matches. If user successfully signins you create the token.
const token = jwt.sign({ _id: user._id, email: user.email }, "this-is-secret", {
expiresIn: "1h",
});
this token is sent to the browser, whenever user make requests, it manually attachs this token to the req, and sends the request to your server. You check if the token is valid, by using the secret key (in this case "this-is-secret").
const decodedToken = jwt.verify(token, "this-is-secret")
req.userId = decodedToken.userId;
now "userId" is attached to the req object. Now when you fetch the data from database, the items that you are fetching, you write a query that (implementation depends on which database you are using)
book.userId=req.userId