From 6f01e00c7e189b45093b031b4065f4abc0d3b727 Mon Sep 17 00:00:00 2001
From: Khalim Conn-Kowlessar <kconnkowlessar@gmail.com>
Date: Mon, 17 Jul 2023 17:16:52 +0100
Subject: [PATCH] Added placeholder code for user validation and implemented
 jwt expiry checking

---
 backend/app/dependencies.py | 32 ++++++++++++++++++++------------
 1 file changed, 20 insertions(+), 12 deletions(-)

diff --git a/backend/app/dependencies.py b/backend/app/dependencies.py
index 685e794f..07fa3c00 100644
--- a/backend/app/dependencies.py
+++ b/backend/app/dependencies.py
@@ -1,13 +1,17 @@
 from fastapi import Depends, HTTPException, status, Request
 from fastapi.security import APIKeyHeader, OAuth2PasswordBearer
-from jose import JWTError, jwe
+from jose import JWTError, jwe, jwt
 from Crypto.Protocol.KDF import HKDF
 from Crypto.Hash import SHA256
 from typing import Any
 import json
+import logging
 from app.config import get_settings
 
 
+logger = logging.getLogger(__name__)
+
+
 api_key_header = APIKeyHeader(name=get_settings().API_KEY_NAME, auto_error=False)
 oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")
 
@@ -30,6 +34,10 @@ def get_user(user_id: str):
         user = None
         if user_id == "known_id":
             user = {"id": user_id, "name": "Known User"}
+        else:
+            print("IMPLEMENT ME! - fetch user from database")
+            user = {"id": user_id, "name": "Dummy User"}
+
         return user
 
 
@@ -65,24 +73,24 @@ def validate_jwt_token(token: str = Depends(oauth2_scheme)):
         # The SECRET_KEY should match the NEXTAUTH_SECRET in the front end
         try:
             payload = get_token_payload(token, get_settings().SECRET_KEY)
-        except Exception as e:
-            print(e)
+        except jwt.ExpiredSignatureError:
+            logger.error("JWT token has expired.")
             raise credentials_exception
+        except Exception as e:
+            logger.error(f"An error occurred while validating the token: {e}")
+            raise credentials_exception
+
         user_id: str = payload.get("dbId")
         if user_id is None:
+            logger.error("No user ID found in the JWT token.")
             raise credentials_exception
+
         user = get_user(user_id=user_id)
         if user is None:
+            logger.error(f"No user found for user ID: {user_id}.")
             raise credentials_exception
+
         return user
     except JWTError:
+        logger.error("An error occurred while decoding the JWT token.")
         raise credentials_exception
-
-
-async def validate_token(token: str = Depends(oauth2_scheme), request: Request = None):
-    token_data = validate_jwt_token(token)
-    if not token_data:
-        raise HTTPException(
-            status_code=status.HTTP_403_FORBIDDEN, detail="Could not validate credentials"
-        )
-    return token