Aniworld/docs/instructions.md

# Aniworld Web Application Development Instructions

This document provides detailed tasks for AI agents to implement a modern web application for the Aniworld anime download manager. All tasks should follow the coding guidelines specified in the project's copilot instructions.

## Project Overview

The goal is to create a FastAPI-based web application that provides a modern interface for the existing Aniworld anime download functionality. The core anime logic should remain in `SeriesApp.py` while the web layer provides REST API endpoints and a responsive UI.

## Architecture Principles

- **Single Responsibility**: Each file/class has one clear purpose
- **Dependency Injection**: Use FastAPI's dependency system
- **Clean Separation**: Web layer calls core logic, never the reverse
- **File Size Limit**: Maximum 500 lines per file
- **Type Hints**: Use comprehensive type annotations
- **Error Handling**: Proper exception handling and logging

## Additional Implementation Guidelines

### Code Style and Standards

- **Type Hints**: Use comprehensive type annotations throughout all modules
- **Docstrings**: Follow PEP 257 for function and class documentation
- **Error Handling**: Implement custom exception classes with meaningful messages
- **Logging**: Use structured logging with appropriate log levels
- **Security**: Validate all inputs and sanitize outputs
- **Performance**: Use async/await patterns for I/O operations

## 📞 Escalation

If you encounter:

- Architecture issues requiring design decisions
- Tests that conflict with documented requirements
- Breaking changes needed
- Unclear requirements or expectations

**Document the issue and escalate rather than guessing.**

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## <20> Credentials

**Admin Login:**

- Username: `admin`
- Password: `Hallo123!`

---

## <20>📚 Helpful Commands

```bash
# Run all tests
conda run -n AniWorld python -m pytest tests/ -v --tb=short

# Run specific test file
conda run -n AniWorld python -m pytest tests/unit/test_websocket_service.py -v

# Run specific test class
conda run -n AniWorld python -m pytest tests/unit/test_websocket_service.py::TestWebSocketService -v

# Run specific test
conda run -n AniWorld python -m pytest tests/unit/test_websocket_service.py::TestWebSocketService::test_broadcast_download_progress -v

# Run with extra verbosity
conda run -n AniWorld python -m pytest tests/ -vv

# Run with full traceback
conda run -n AniWorld python -m pytest tests/ -v --tb=long

# Run and stop at first failure
conda run -n AniWorld python -m pytest tests/ -v -x

# Run tests matching pattern
conda run -n AniWorld python -m pytest tests/ -v -k "auth"

# Show all print statements
conda run -n AniWorld python -m pytest tests/ -v -s

#Run app
conda run -n AniWorld python -m uvicorn src.server.fastapi_app:app --host 127.0.0.1 --port 8000 --reload
```

---

## Implementation Notes

1. **Incremental Development**: Implement features incrementally, testing each component thoroughly before moving to the next
2. **Code Review**: Review all generated code for adherence to project standards
3. **Documentation**: Document all public APIs and complex logic
4. **Testing**: Maintain test coverage above 80% for all new code
5. **Performance**: Profile and optimize critical paths, especially download and streaming operations
6. **Security**: Regular security audits and dependency updates
7. **Monitoring**: Implement comprehensive monitoring and alerting
8. **Maintenance**: Plan for regular maintenance and updates

---

## Task Completion Checklist

For each task completed:

- [ ] Implementation follows coding standards
- [ ] Unit tests written and passing
- [ ] Integration tests passing
- [ ] Documentation updated
- [ ] Error handling implemented
- [ ] Logging added
- [ ] Security considerations addressed
- [ ] Performance validated
- [ ] Code reviewed
- [ ] Task marked as complete in instructions.md
- [ ] Infrastructure.md updated and other docs
- [ ] Changes committed to git; keep your messages in git short and clear
- [ ] Take the next task

---

## TODO List:

✅ **Task Completed Successfully**

### Issue Fixed: TypeError: 'async for' requires an object with __aiter__ method

**Problem:**
The BackgroundLoaderService was crashing when trying to load series data with the error:
```
TypeError: 'async for' requires an object with __aiter__ method, got _AsyncGeneratorContextManager
```

This error occurred in `_load_series_data` method at line 282 of [background_loader_service.py](src/server/services/background_loader_service.py).

**Root Cause:**
The code was incorrectly using `async for db in get_db_session():` to get a database session. However, `get_db_session()` is decorated with `@asynccontextmanager`, which returns an async context manager (not an async iterator). Async context managers must be used with `async with`, not `async for`.

**Solution:**
Changed the database session acquisition from:
```python
async for db in get_db_session():
    # ... code ...
    break  # Exit loop after first iteration
```

To the correct pattern:
```python
async with get_db_session() as db:
    # ... code ...
```

**Files Modified:**
1. [src/server/services/background_loader_service.py](src/server/services/background_loader_service.py) - Fixed async context manager usage
2. [tests/unit/test_background_loader_session.py](tests/unit/test_background_loader_session.py) - Created comprehensive unit tests

**Tests:**
- ✅ 5 new unit tests for background loader database session handling (all passing)
- ✅ Tests verify proper async context manager usage
- ✅ Tests verify error handling and progress tracking
- ✅ Tests verify episode and NFO loading logic
- ✅ Includes test demonstrating the difference between `async with` and `async for`

**Verification:**
The fix allows the background loader service to properly load series data including episodes, NFO files, logos, and images without crashing.

---

## Next Tasks:

No pending tasks at this time.