chore: api authentication

Author: ayushkrtiwari

src/quant_research_starter/api/auth.py

@@ -0,0 +1,68 @@
+"""JWT authentication utilities and dependencies."""
+from __future__ import annotations
+import os
+from datetime import datetime, timedelta
+from typing import Optional
+
+from passlib.context import CryptContext
+from jose import JWTError, jwt
+from fastapi import Depends, HTTPException, status
+from fastapi.security import OAuth2PasswordBearer
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from . import models, db
+
+SECRET_KEY = os.getenv("JWT_SECRET", "dev-secret-change-me")
+ALGORITHM = "HS256"
+ACCESS_TOKEN_EXPIRE_MINUTES = int(os.getenv("JWT_EXPIRE_MINUTES", "60"))
+
+pwd_ctx = CryptContext(schemes=["bcrypt"], deprecated="auto")
+oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/api/auth/token")
+
+
+def verify_password(plain_password: str, hashed_password: str) -> bool:
+    return pwd_ctx.verify(plain_password, hashed_password)
+
+
+def get_password_hash(password: str) -> str:
+    return pwd_ctx.hash(password)
+
+
+def create_access_token(data: dict, expires_delta: Optional[timedelta] = None) -> str:
+    to_encode = data.copy()
+    if expires_delta:
+        expire = datetime.utcnow() + expires_delta
+    else:
+        expire = datetime.utcnow() + timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
+    to_encode.update({"exp": expire})
+    return jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
+
+
+async def get_current_user(token: str = Depends(oauth2_scheme), session: AsyncSession = Depends(db.get_session)):
+    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
+    except JWTError:
+        raise credentials_exception
+
+    q = await session.execute(
+        models.User.__table__.select().where(models.User.username == username)
+    )
+    row = q.first()
+    if not row:
+        raise credentials_exception
+    user = row[0]
+    return user
+
+
+async def require_active_user(current_user=Depends(get_current_user)):
+    if not current_user.is_active:
+        raise HTTPException(status_code=400, detail="Inactive user")
+    return current_user