Added auth

backend/app/auth.py

@@ -0,0 +1,93 @@
+from datetime import datetime, timedelta
+from typing import Optional
+from jose import JWTError, jwt
+from passlib.context import CryptContext
+from fastapi import Depends, HTTPException, status, Header
+from sqlalchemy.orm import Session
+from .database import get_db
+from .models import User
+
+# Configuration
+SECRET_KEY = "your-secret-key-change-in-production"  # Change this in production!
+ALGORITHM = "HS256"
+ACCESS_TOKEN_EXPIRE_MINUTES = 720
+
+pwd_context = CryptContext(schemes=["argon2"], deprecated="auto")
+
+
+def hash_password(password: str) -> str:
+    """Hash a password using bcrypt"""
+    return pwd_context.hash(password)
+
+
+def verify_password(plain_password: str, hashed_password: str) -> bool:
+    """Verify a password against its hash"""
+    return pwd_context.verify(plain_password, hashed_password)
+
+
+def create_access_token(data: dict, expires_delta: Optional[timedelta] = None):
+    """Create a JWT access token"""
+    to_encode = data.copy()
+    if expires_delta:
+        expire = datetime.utcnow() + expires_delta
+    else:
+        expire = datetime.utcnow() + timedelta(minutes=15)
+    to_encode.update({"exp": expire})
+    encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
+    return encoded_jwt
+
+
+def get_current_user(authorization: Optional[str] = Header(None), db: Session = Depends(get_db)) -> User:
+    """Get the current authenticated user from JWT token"""
+    if not authorization:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Missing authorization header",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    
+    try:
+        scheme, credentials = authorization.split()
+        if scheme.lower() != "bearer":
+            raise ValueError("Invalid auth scheme")
+    except (ValueError, AttributeError):
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Invalid authorization header format",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    
+    try:
+        payload = jwt.decode(credentials, SECRET_KEY, algorithms=[ALGORITHM])
+        username: str = payload.get("sub")
+        if username is None:
+            raise HTTPException(
+                status_code=status.HTTP_401_UNAUTHORIZED,
+                detail="Invalid authentication credentials",
+                headers={"WWW-Authenticate": "Bearer"},
+            )
+    except JWTError:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Invalid authentication credentials",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    
+    user = db.query(User).filter(User.username == username).first()
+    if user is None:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Invalid authentication credentials",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    return user
+
+
+def get_current_admin_user(current_user: User = Depends(get_current_user)) -> User:
+    """Get the current user and verify they are an admin"""
+    if not current_user.is_admin:
+        raise HTTPException(
+            status_code=status.HTTP_403_FORBIDDEN,
+            detail="Not enough permissions. Admin access required."
+        )
+    return current_user