2.1.2. AuthenticateUser

Implement this function:

authenticate_user(username: str, password: str) → User

Returns an instance of an User that includes all necessary data the client program needs to operate on behalf of the already-created user identified by username and password. However, raises a util.DropboxError in the following circumstances:

  • If no user with username exists.

  • If the provided password is invalid for the given username.

  • If authentication cannot complete due to malicious action, such as an integrity violation.

Parameters:

  • username (str) – The username of the user

  • password (str) – The password of the user

Returns:

A User instance corresponding to the user identified by username

Return type:

User

Raises:

DropboxError – if an error case occurred

Warning

This function may be called multiple times with the same credentials to obtain multiple, authenticated User instances for the same user. Any actions taken by any authenticated instances of the same user must be immediately visible to all other User instances corresponding to that user.

For example, let \(u_1\) and \(u_2\) be two instances of the same user running on different machines. Then, if \(u_1\) uploads a file \(F\), \(u_2\) should be able to download \(F\) immediately.

Note

For simplicity, your system does not need to support concurrent operations—that is, we guarantee that individual operations between clients will be performed serially, and you should implement your client with the assumption that no other code will be running at the same time.