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Week 10 Assignment

Task 1 - Build a simple authentication system

In this task, you will implement a simple yet robust authentication system using Spring Security. Apply the best practices from this week's content and combine them together.

Requirements

Set up a security configuration class (filter chain, password encoder bean).
Implement /register, /login, and /logout endpoints to handle user registration, login, and logout.
- /register accepts a username and password and creates a new user in the database.
- /login accepts a username / password combination, verifies the password against the database, and returns a session token (or JWT) to the user.
- /logout ends the user's session (see the note on logout below).
Add a protected /profile endpoint that returns the logged-in user, or an error for unauthenticated requests.

Note: /register and /login are public endpoints. /logout and /profile are protected and require a valid token.

Guidelines

Store user passwords securely using bcrypt, with a strength (hash rounds) of 12.
When creating a new user, assign a good random hard-to-guess user ID.
For authentication, choose one approach:
1. Session tokens — store the session server-side (e.g. in the database). /logout deletes the session record.
2. JWT (stateless) — no server-side session. For /logout, the client discards the token. No logic needed to be implemented on the server-side.
Keep your secrets (JWT signing key, etc.) in environment variables — never hardcoded in the source.
Return the correct HTTP status codes (e.g. 401 for unauthenticated, 200 on success).
Use Spring Security's filter chain.

Starter project

We have set up a simple project for you with controllers, services and a repository. Feel free to change any code.

Submission

Follow the Assignment submission guide to submit

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