auth.py

from datetime import datetime, timedelta
from jose import JWTError, jwt
from fastapi import Depends, HTTPException, status
from fastapi.security import OAuth2PasswordBearer
from passlib.context import CryptContext
from models import User
from tortoise.exceptions import DoesNotExist
import os
from dotenv import load_dotenv
from schemas import (
    User as UserSchema,
    TokenData,
    Transaction as TransactionSchema,
)
import bcrypt

load_dotenv()

SECRET_KEY = f"{os.environ['SECRET_KEY']}"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")

async def get_user_by_email(email: str):
    return await User.get_or_none(email=email)

def hash_password(password: str) -> str:
    pwd_bytes = password.encode('utf-8')
    salt = bcrypt.gensalt()
    hashed_password = bcrypt.hashpw(pwd_bytes, salt)
    return hashed_password.decode('utf-8')

# Check if the provided password matches the stored password (hashed)
def verify_password(plain_password: str, hashed_password: str) -> bool:
    password_byte_enc = plain_password.encode('utf-8')
    if isinstance(hashed_password, str):
        hashed_password = hashed_password.encode('utf-8')
    return bcrypt.checkpw(password_byte_enc, hashed_password)


async def authenticate_user(email: str, password: str):
    try:
        user = await User.get(email=email)
    except DoesNotExist:
        return False
    if not verify_password(password, user.hashed_password):
        return False
    return user

def create_access_token(data: dict, expires_delta: timedelta = None):
    to_encode = data.copy()
    if expires_delta:
        expire = datetime.now() + expires_delta
    else:
        expire = datetime.now() + timedelta(minutes=15)
    to_encode.update({"exp": expire})
    encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
    return encoded_jwt

import logging

logger = logging.getLogger("uvicorn.error")

async def get_user(token: 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])
        email: str = payload.get("sub")
        if email is None:
            raise credentials_exception
        token_data = TokenData(email=email)
    except JWTError:
        raise credentials_exception
    user = await get_user_by_email(email=token_data.email)
    if user is None:
        raise credentials_exception
    return user

async def get_current_active_user(current_user: User = Depends(get_user)):
    return current_user