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codellama_auth_gen.py

from passlib.context import CryptContext
from jose import jwt
import datetime

SECRET_KEY = "YOUR-SECRET-KEY"  # Replace this with your secret key
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")

class User:
    def __init__(self, username: str, password: str):
        self.username = username
        self.password = pwd_context.hash(password)  # Hash the password using bcrypt

    def verify_password(self, password: str):
        return pwd_context.verify(password, self.password)



from fastapi import FastAPI, HTTPException, Depends, status
from fastapi.security import OAuth2PasswordBearer
from pydantic import BaseModel

app = FastAPI()
oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")

# Mock user database (in practice this would be a real database)
user_db = {
    "user1": User("user1", "password1"),
    "user2": User("user2", "password2"),
}

class TokenData(BaseModel):
    username: str

def authenticate_user(username: str, password: str):
    user = user_db.get(username)
    if not user or not user.verify_password(password):
        return False
    return user

async def get_current_user(token: str = Depends(oauth2_scheme)):
    credentials_exception = HTTPException(
        status_code=status.HTTP_401_UNAUTHORIZED,
        detail="Invalid authentication credentials",
        headers={"WWW-Authenticate": "Bearer"},
    )
    try:
        payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
        username: str = payload.get("sub")
        if username is None or (user := user_db.get(username)) is None:
            raise credentials_exception
    except jwt.JWTError:
        raise credentials_exception
    return user

@app.post("/token", response_model=TokenData)
async def login_for_access_token(form_data: dict):
    username = form_data.get("username")
    password = form_data.get("password")
    user = authenticate_user(username, password)
    if not user:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Incorrect username or password",
            headers={"WWW-Authenticate": "Bearer"},
        )
    access_token_expires = datetime.timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
    access_token = create_access_token(
        data={"sub": user.username}, expires_delta=access_token_expires
    )
    return {"access_token": access_token, "token_type": "bearer"}