forum-app/backend/routers/auth.py

from typing import Annotated
from fastapi import APIRouter, Depends
from pydantic import BaseModel
from passlib.context import CryptContext
from sqlalchemy.orm import Session
from starlette import status
from fastapi.security import OAuth2PasswordRequestForm

from models import User
from database import SessionLocal

router = APIRouter()

bcrypt_context = CryptContext(schemes=['bcrypt'], deprecated='auto')


def get_db():
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()


db_dependency = Annotated[Session, Depends(get_db)]


def authenticate_user(username: str, password: str, db):
    user = db.query(User).filter(User.username == username).first()
    if not user:
        return False
    if not bcrypt_context.verify(password, user.password):
        return False
    return True


class CreateUser(BaseModel):
    username: str
    email: str
    password: str


@router.post('/auth/create', status_code=status.HTTP_201_CREATED)
async def create_user(db: db_dependency, data: CreateUser):
    create_user_model = User(
        username=data.username,
        email=data.email,
        password=bcrypt_context.hash(data.password),
        role='admin'
    )

    db.add(create_user_model)
    db.commit()


@router.post('/auth/token', status_code=status.HTTP_200_OK)
async def get_token(
        form_data: Annotated[OAuth2PasswordRequestForm, Depends()],
        db: db_dependency
):
    user = authenticate_user(form_data.username, form_data.password, db)
    if user:
        return "you good fam"

    return "failed authentication"