Implement the login endpoint which authenticates an user using either email or username. The backend must recognize which of the user's ids are provided and then authenticate the user in question.
When logging in, a JWT (JSON Web Token) must be issued and retrieved to the client, this JWT is used on every endpoint but the login endpoint (this endpoint) and the register endpoint (implemented on #12).
Implement the login endpoint which authenticates an user using either email or username. The backend must recognize which of the user's ids are provided and then authenticate the user in question.
When logging in, a JWT (JSON Web Token) must be issued and retrieved to the client, this JWT is used on every endpoint but the login endpoint (this endpoint) and the register endpoint (implemented on #12).
This issue depends on #11 and #12.