Aniworld/docs/logging_implementation_summary.md

# Logging Implementation Summary

## What Was Implemented

### 1. Core Logging Infrastructure (`src/infrastructure/logging/`)

-   **`logger.py`**: Main logging configuration module

    -   `setup_logging()`: Configures both console and file handlers
    -   `get_logger()`: Retrieves logger instances for specific modules
    -   Follows Python logging best practices with proper formatters

-   **`uvicorn_config.py`**: Uvicorn-specific logging configuration

    -   Custom logging configuration dictionary for uvicorn
    -   Ensures uvicorn logs are captured in both console and file
    -   Configures multiple loggers (uvicorn, uvicorn.error, uvicorn.access, aniworld)

-   **`__init__.py`**: Package initialization
    -   Exports public API: `setup_logging`, `get_logger`, `get_uvicorn_log_config`

### 2. FastAPI Integration

Updated `src/server/fastapi_app.py` to:

-   Import and use the logging infrastructure
-   Call `setup_logging()` during application startup (in `lifespan()`)
-   Replace all `print()` statements with proper logger calls
-   Use lazy formatting (`logger.info("Message: %s", value)`)

### 3. Startup Scripts

-   **`run_server.py`**: Python startup script

    -   Uses the custom uvicorn logging configuration
    -   Recommended way to start the server

-   **`start_server.sh`**: Bash startup script
    -   Wrapper around `run_server.py`
    -   Made executable with proper shebang

### 4. Documentation

-   **`docs/logging.md`**: Comprehensive logging guide
    -   How to run the server
    -   Log file locations
    -   Log format examples
    -   Troubleshooting guide
    -   Programmatic usage examples

## Log Outputs

### Console Output

```
INFO:     Starting FastAPI application...
INFO:     Loaded anime_directory from config: /home/lukas/Volume/serien/
INFO:     Server running on http://127.0.0.1:8000
INFO:     API documentation available at http://127.0.0.1:8000/api/docs
```

### File Output (`logs/fastapi_app.log`)

```
2025-10-25 17:31:19 - aniworld - INFO - ============================================================
2025-10-25 17:31:19 - aniworld - INFO - Logging configured successfully
2025-10-25 17:31:19 - aniworld - INFO - Log level: INFO
2025-10-25 17:31:19 - aniworld - INFO - Log file: /home/lukas/Volume/repo/Aniworld/logs/fastapi_app.log
2025-10-25 17:31:19 - aniworld - INFO - ============================================================
2025-10-25 17:31:19 - aniworld - INFO - Starting FastAPI application...
2025-10-25 17:31:19 - aniworld - INFO - Loaded anime_directory from config: /home/lukas/Volume/serien/
2025-10-25 17:31:19 - src.core.SeriesApp - INFO - Initializing SeriesApp...
2025-10-25 17:31:19 - src.core.SerieScanner - INFO - Initialized SerieScanner...
2025-10-25 17:31:19 - aniworld - INFO - SeriesApp initialized with directory: /home/lukas/Volume/serien/
2025-10-25 17:31:19 - aniworld - INFO - FastAPI application started successfully
2025-10-25 17:31:19 - aniworld - INFO - Server running on http://127.0.0.1:8000
2025-10-25 17:31:19 - aniworld - INFO - API documentation available at http://127.0.0.1:8000/api/docs
```

## How to Use

### Starting the Server

**Recommended:**

```bash
conda run -n AniWorld python run_server.py
```

**Alternative:**

```bash
./start_server.sh
```

**View logs in real-time:**

```bash
tail -f logs/fastapi_app.log
```

### In Code

```python
from src.infrastructure.logging import get_logger

logger = get_logger(__name__)

logger.info("Message: %s", value)
logger.warning("Warning: %s", warning_msg)
logger.error("Error occurred", exc_info=True)
```

## Configuration

Set log level via environment variable or `.env` file:

```bash
export LOG_LEVEL=INFO  # or DEBUG, WARNING, ERROR
```

## Features

✅ **Console logging**: Colored, easy-to-read format  
✅ **File logging**: Detailed with timestamps and logger names  
✅ **Automatic log directory creation**: `logs/` created if missing  
✅ **Uvicorn integration**: All uvicorn logs captured  
✅ **Multiple loggers**: Different loggers for different modules  
✅ **Configurable log level**: Via environment variable  
✅ **Proper formatting**: Uses lazy formatting for performance  
✅ **Startup/shutdown logging**: Clear application lifecycle logs  
✅ **Error tracebacks**: Full exception context with `exc_info=True`

## Files Created/Modified

### Created:

-   `src/infrastructure/logging/logger.py`
-   `src/infrastructure/logging/uvicorn_config.py`
-   `src/infrastructure/logging/__init__.py`
-   `run_server.py`
-   `start_server.sh`
-   `docs/logging.md`
-   `docs/logging_implementation_summary.md` (this file)

### Modified:

-   `src/server/fastapi_app.py`: Integrated logging throughout

## Testing

The implementation has been tested and verified:

-   ✅ Log file created at `logs/fastapi_app.log`
-   ✅ Startup messages logged correctly
-   ✅ Application configuration loaded and logged
-   ✅ Uvicorn logs captured
-   ✅ File watching events logged
-   ✅ Shutdown messages logged

## Next Steps

Consider adding:

1. **Log rotation**: Use `RotatingFileHandler` to prevent log files from growing too large
2. **Structured logging**: Use `structlog` for JSON-formatted logs
3. **Log aggregation**: Send logs to a centralized logging service
4. **Performance monitoring**: Add timing logs for slow operations
5. **Request logging middleware**: Log all HTTP requests/responses