# ZMP Authentication Provider

A Python library for authentication using Basic Auth and OIDC (OpenID Connect).

## Description

This library provides authentication functionality using both Basic Authentication and OpenID Connect protocols. It's designed to be flexible and easy to integrate into your Python applications.

## Installation

```bash
pip install zmp-authentication-provider
```

## Requirements

- Python >= 3.12, < 4.0

## Dependencies

- pydantic >= 2.10.6
- pydantic-settings >= 2.9.1, < 3.0.0
- fastapi >= 0.115.11, < 0.116.0
- python-dotenv >= 1.0.1, < 2.0.0
- pyjwt >= 2.10.1, < 3.0.0
- requests >= 2.32.3, < 3.0.0
- cryptography >= 42.0.0, < 45.0
- pymongo >= 4.12.0, < 5.0.0
- motor >= 3.7.0, < 4.0.0
- redis >= 5.2.0, < 6.0.0
- uvicorn >= 0.35.0, < 0.36.0
- starlette >= 0.46.2, < 0.47.0
- starlette-csrf >= 3.0.0, < 4.0.0
- colorlog >= 6.9.0, < 7.0.0

## Usage

```python
# FastAPI main.py
from contextlib import asynccontextmanager
from fastapi import FastAPI, Request, Response
from motor.motor_asyncio import AsyncIOMotorClient
from redis.asyncio import Redis
from typing import Callable

from zmp_authentication_provider.routes.auth import router as auth_router
from zmp_authentication_provider.service.auth_service import AuthService
from zmp_authentication_provider.utils.redis_session_store import RedisSessionStore
from zmp_authentication_provider.setting import auth_default_settings, redis_settings

@asynccontextmanager
async def lifespan(app: FastAPI):
    """Lifespan for the FastAPI app."""
    try:
        # 1. Initialize MongoDB Connection
        mongodb_client = AsyncIOMotorClient(mongodb_uri)
        database = mongodb_client[database_name]

        # 2. Initialize Redis Session Store
        redis_client = Redis.from_url(
            f"redis://{redis_settings.host}:{redis_settings.port}",
            encoding="utf-8",
            decode_responses=redis_settings.decode_responses,
            db=redis_settings.db,
            password=redis_settings.password,
        )
        app.state.redis_session_store = RedisSessionStore(
            redis_client=redis_client,
            session_ttl=auth_default_settings.session_ttl
        )

        # 3. Initialize Auth Service
        app.state.auth_service = await AuthService.initialize(database=database)

        yield

    finally:
        if mongodb_client:
            await mongodb_client.close()
        if redis_client:
            await redis_client.close()

app = FastAPI(
    title="Your Application",
    version="0.1.0",
    lifespan=lifespan,
)

app.include_router(auth_router, tags=["auth"], prefix="/api/v1")


# router.py
from zmp_authentication_provider.auth.oauth2_keycloak import (
    TokenData,
    get_current_user,
)


@router.put(
    "/jobs/{job_id}",
    summary="Update job details",
    description="Update the details of an existing job. Only the provided fields will be updated.",
    response_description="The updated job information.",
    response_class=JSONResponse,
    response_model=Job,
    response_model_by_alias=False,
    response_model_exclude_none=False,
)
async def update_job(
    job_update_request: JobUpdateRequest,
    job_id: str = Path(..., description="The ID of the job to update"),
    service: AIOpsService = Depends(_get_aiops_service),
    oauth_user: TokenData = Depends(get_current_user),
):
    """Update a job's information."""
    job = Job(
        id=job_id,
        updated_by=oauth_user.username,
        **job_update_request.model_dump(exclude_unset=True),
    )
    return await service.modify_job(job=job)

```

### Sliding Session Management

To implement sliding session expiration (automatic session extension on user activity), add the following middleware to your FastAPI application:

```python
from typing import Callable
from fastapi import Request, Response
from zmp_authentication_provider.setting import auth_default_settings
from zmp_authentication_provider.utils.redis_session_store import RedisSessionStore

@app.middleware("http")
async def sliding_session_middleware(
    request: Request, call_next: Callable[[Request], Response]
):
    """Sliding session middleware.

    This middleware extends session TTL on every request (sliding expiration).
    It updates both Redis TTL and cookie max-age to keep them synchronized.
    """
    resp: Response = await call_next(request)

    # Apply sliding expiration for existing sessions
    session_id = request.cookies.get(auth_default_settings.session_id_cookie_name)
    session_id_created = getattr(request.state, "session_id_created", False)
    
    if session_id and not session_id_created:
        try:
            redis_session_store: RedisSessionStore = request.app.state.redis_session_store
            
            # Extend both Redis TTL and cookie max-age (sliding expiration)
            # Refresh session TTL & cookie max-age if needed
            if await redis_session_store.need_refresh(session_id, threshold_seconds=600):
                # 1. Refresh session TTL
                await redis_session_store.reset_ttl(session_id)

                # 2. Update cookie max-age                
                resp.set_cookie(
                    key=auth_default_settings.session_id_cookie_name,
                    value=session_id,
                    max_age=auth_default_settings.session_max_age,
                    httponly=auth_default_settings.session_https_only,
                    secure=auth_default_settings.session_secure,
                    samesite=auth_default_settings.session_same_site,
                    domain=auth_default_settings.session_domain,
                )
            
        except Exception as e:
            # 세션 연장 실패가 사용자 응답을 막지 않도록 로그만 남기고 무시
            logger.error(f"[Sliding Session] Failed to extend session {session_id}: {e}")

    return resp
```

This middleware automatically extends the session expiration time on every request, ensuring users remain logged in while actively using the application. It includes an optimization to only refresh the session if the remaining TTL is below a certain threshold (e.g., 600 seconds) to reduce Redis write operations.

### Environment Configuration

Put the below value into the`.env` file in your project root:

```env
# Authentication default configuration
AUTH_HTTP_CLIENT_SSL_VERIFY="True"
AUTH_APPLICATION_ENDPOINT="${YOUR_API_ENDPOINT}"
AUTH_SESSION_TTL="1800"
AUTH_SESSION_MAX_AGE="1800"
AUTH_SESSION_DOMAIN="your-domain.com"
AUTH_SESSION_SECURE="True"
AUTH_SESSION_HTTPS_ONLY="True"
AUTH_SESSION_SAME_SITE="lax"

# Keycloak configuration
KEYCLOAK_SERVER_URL="https://your-keycloak-server.com/auth"
KEYCLOAK_REALM="your-realm"
KEYCLOAK_CLIENT_ID="your-client-id"
KEYCLOAK_CLIENT_SECRET="your-client-secret"
KEYCLOAK_REDIRECT_URI="${AUTH_APPLICATION_ENDPOINT}/api/v1/auth/oauth2/callback"
KEYCLOAK_ALGORITHM="RS256"

# Redis configuration
REDIS_HOST="localhost"
REDIS_PORT="6379"
REDIS_DB="0"
REDIS_PASSWORD=""
REDIS_DECODE_RESPONSES="True"
REDIS_SESSION_PREFIX="session:"
REDIS_SESSION_TTL="1800"
```

## Testing
### Test flow
```
# for obtaining csrf token
http://0.0.0.0:7900/api/v1/auth/home

# setting the Referer header using the chrome extension
Referer = http://0.0.0.0:7900/api/v1/auth/access-token

# Login using the keycloak oauth flow and redirect_uri=http://0.0.0.0:7900/api/v1/auth/oauth2/callback
# Use new reqeust to the keycloak
https://keycloak.ags.cloudzcp.net/auth/realms/ags/protocol/openid-connect/auth?response_type=code&client_id=zmp-client&state=.eJwFwUkOgjAAAMC_eCeRxRaODYKUraxFTo1FQMSURkSE1ztzQJi7wswEfs1j4E953dHc7SaF0IQoy81G4aBFupiCWm3NL1dlYeD1hJlgnUv7sXKJjWjpIYc52rHeVxyXM2kWjoEy1Invb94u3yIiufeT6PFJWoapdQXnewZVjmAwmOZThq3GssJfeawYVSqAnpet7C6w5xVMrWgDTaNV6eEPQtc4PA.DKauCaFnrjVwj1P3RaYa6GBH7VM::http://0.0.0.0:7900/api/v1/auth/access-token&redirect_uri=http://0.0.0.0:7900/api/v1/auth/oauth2/callback&scope=openid%20profile%20email

# connect home page
http://0.0.0.0:7900/api/v1/auth/home
```

## Development

### Development Dependencies

```bash
pip install pytest pytest-cov pytest-watcher pytest-asyncio certifi ruff
```

### Quality Tools

```bash
pip install pre-commit
```

## Project Structure

The main package is located in the `src/zmp_authentication_provider` directory.

## Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

## License

This project is licensed under the terms of the license included in the repository.

## Author

- Kilsoo Kang (kilsoo75@gmail.com)

## Links

- [Homepage](https://github.com/cloudz-mp)
- [Repository](https://github.com/cloudz-mp/zmp-authentication-provider)
- [Documentation](https://github.com/cloudz-mp/zmp-authentication-provider)
- [Issue Tracker](https://github.com/cloudz-mp/zmp-authentication-provider/issues)
