def authenticate_user(username: str, password: str, repo: AbstractRepository):
authenticated = False
user = repo.get_user(username)
if user is not None:
authenticated = check_password_hash(user.password, password)
if not authenticated:
raise AuthenticationException
def add_user(username: str, password: str, repo: AbstractRepository):
# Check that the given username is available.
user = repo.get_user(username)
if user is not None:
raise NameNotUniqueException
# Encrypt password so that the database doesn't store passwords 'in the clear'.
password_hash = generate_password_hash(password)
# Create and store the new User, with password encrypted.
user = User(username, password_hash)
repo.add_user(user)
def add_comment(article_id: int, comment_text: str, username: str,
repo: AbstractRepository):
# Check that the article exists.
article = repo.get_article(article_id)
if article is None:
raise NonExistentMoviesException
user = repo.get_user(username)
if user is None:
raise UnknownUserException
# Create comment.
comment = make_comment(comment_text, user, article)
# Update the repository.
repo.add_comment(comment)
def get_user(username: str, repo: AbstractRepository):
user = repo.get_user(username)
if user is None:
raise UnknownUserException
return user_to_dict(user)