Gros refactoring

backend/authentication.py

@@ -0,0 +1,102 @@
+from datetime import timedelta, datetime, timezone
+from typing import Annotated
+
+import jwt
+from fastapi import Depends, HTTPException
+from passlib.exc import InvalidTokenError
+from starlette import status
+
+from config import SECRET_KEY, get_fake_users_db, pwd_context, oauth2_scheme, ALGORITHM
+from models import UserInDB, User
+
+import base64
+import hashlib
+import hmac
+
+def verify_password(plain_password, hashed_password):
+    try:
+        # Decode the stored hash
+        decoded = base64.b64decode(hashed_password)
+        salt, stored_hash = decoded[:16], decoded[16:]
+        
+        # Hash the plain password with the same salt
+        key = hashlib.sha256(salt).digest()
+        new_hash = hmac.new(key, plain_password.encode('utf-8'), hashlib.sha256).digest()
+        
+        # Compare the new hash with the stored hash
+        return hmac.compare_digest(new_hash, stored_hash)
+    except (TypeError, ValueError, base64.binascii.Error):
+        # This will catch any decoding errors or incorrect hash format
+        return False
+
+
+def get_password_hash(password):
+    return pwd_context.hash(password)
+
+
+def get_user(db, username: str):
+    if username in db:
+        user_dict = db[username]
+        return UserInDB(**user_dict)
+
+
+from fastapi import HTTPException, status
+
+def authenticate_user(fake_db, username: str, password: str):
+    user = get_user(fake_db, username)
+    if not user:
+        print(f"User not found: {username}")  # Debug print
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Incorrect username",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    print(f"Stored hash: {user.hashed_password}")  # Debug print
+    print(f"Provided password: {password}")  # Debug print
+    if not verify_password(password, user.hashed_password):
+        print("Password verification failed")  # Debug print
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Incorrect password",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    return user
+
+
+def create_access_token(data: dict, expires_delta: timedelta | None = None):
+    to_encode = data.copy()
+    if expires_delta:
+        expire = datetime.now(timezone.utc) + expires_delta
+    else:
+        expire = datetime.now(timezone.utc) + timedelta(minutes=15)
+    to_encode.update({"exp": expire})
+    encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
+    return encoded_jwt
+
+
+async def get_current_user(token: Annotated[str, Depends(oauth2_scheme)]):
+    credentials_exception = HTTPException(
+        status_code=status.HTTP_401_UNAUTHORIZED,
+        detail="Could not validate credentials",
+        headers={"WWW-Authenticate": "Bearer"},
+    )
+    try:
+        payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
+        username: str = payload.get("sub")
+        if username is None:
+            raise credentials_exception
+        token_data = User(username=username)
+    except InvalidTokenError:
+        raise credentials_exception
+    user = get_user(get_fake_users_db(), username=token_data.username)
+    if user is None:
+        raise credentials_exception
+    return user
+
+
+async def get_current_active_user(
+        current_user: Annotated[User, Depends(get_current_user)],
+):
+    if current_user.disabled:
+        raise HTTPException(status_code=400, detail="Inactive user")
+    return current_user