Basic user model and login authentication :]

app/logic/user_logic.py

@@ -0,0 +1,90 @@
+from datetime import UTC, datetime, timedelta
+from typing import Annotated
+
+import jwt
+from fastapi import Depends, HTTPException, status
+from fastapi.security import OAuth2PasswordBearer
+from pwdlib import PasswordHash
+
+from app.config import Settings
+from app.database import get_from_database_where
+from app.models.token import TokenData
+from app.models.user import User, UserInDB
+
+oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")
+
+password_hash = PasswordHash.recommended()
+
+DUMMY_HASH = password_hash.hash("testpassword")
+
+
+def verify_password(plain_password: str, hashed_password: str):
+    return password_hash.verify(plain_password, hashed_password)
+
+
+def get_password_hash(password: str):
+    return password_hash.hash(password)
+
+
+def get_user(username: str):
+    user_dict = get_from_database_where(User, User.username, username, True)
+    if user_dict is not None:
+        return UserInDB(**user_dict)
+
+
+def authenticate_user(username: str, password: str):
+    user = get_user(username)
+    if not user:
+        verify_password(password, DUMMY_HASH)
+        return False
+    if not verify_password(password, user.hashed_password):
+        return False
+    return user
+
+
+def create_access_token(
+    data: dict[str, str],
+    expires_delta: timedelta | None = None,
+):
+    to_encode = data.copy()
+    if expires_delta:
+        expire = datetime.now(UTC) + expires_delta
+    else:
+        expire = datetime.now(UTC) + timedelta(minutes=15)
+    to_encode.update({"exp": expire})
+    encoded_jwt = jwt.encode(
+        to_encode,
+        Settings.secret_key,
+        algorithm=Settings.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,
+            Settings.secret_key,
+            algorithms=[Settings.algorithm],
+        )
+        username = payload.get("sub")
+        if username is None:
+            raise credentials_exception
+        token_data = TokenData(username=username)
+    except jwt.InvalidTokenError:
+        raise credentials_exception
+    user = get_user(token_data.username)  # type: ignore Look just above here idiot!
+    if user is None:
+        raise credentials_exception
+    return user
+
+
+async def get_current_active_user(
+    current_user: Annotated[User, Depends(get_current_user)],
+):
+    return current_user