1 files changed, 48 insertions, 0 deletions

diff --git a/app/app_sessions.py b/app/app_sessions.py
new file mode 100644
index 0000000..89521fb
--- /dev/null
+++ b/app/app_sessions.py
@@ -0,0 +1,48 @@
+# UGE / L2 / Intro to relational databases / Python project prototype
+# Author: Pacien TRAN-GIRARD
+# Licence: EUPL-1.2
+
+from os import environ
+from functools import partial
+
+from fastapi import Request, HTTPException, status
+from starlette.middleware.sessions import SessionMiddleware
+
+
+# Use a signed-cookie session manager.
+# The default SameSite policy offers some protection against CSRF attacks.
+cookie_key = environ['COOKIE_SECRET_KEY']
+SessionManager = partial(SessionMiddleware, secret_key=cookie_key)
+
+
+class UserSession:
+    """
+    Session decorator for managing user login sessions.
+    """
+
+    def __init__(self, request: Request):
+        self._session = request.session
+
+    def is_logged_in(self) -> bool:
+        return 'user_id' in self._session
+
+    def get_user_id(self) -> int:
+        return self._session['user_id']
+
+    def login(self, user_id: int):
+        self._session['user_id'] = user_id
+
+    def logout(self):
+        self._session.pop('user_id', None)
+
+    @classmethod
+    def authenticated(cls, request: Request) -> 'UserSession':
+        """
+        Returns the authenticated user session or raises an HTTP Exception,
+        dropping the request if the user is not logged in.
+        """
+        session = cls(request)
+        if not session.is_logged_in():
+            raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED)
+
+        return session