# Configuration Persistence for Docker

ShiftScheduler now supports persisting configuration changes in external files, making it suitable for Docker deployments where configuration should survive container rebuilds.

## How it Works

Configuration is automatically saved to and loaded from external JSON files in the `config/` directory:

- `config/shifts.json` - Contains all shift definitions (name, icon, times)
- `config/transport.json` - Contains transport API settings and parameters

## Behavior

1. **Startup**: Service reads from external files if they exist, otherwise uses `appsettings.json` defaults
2. **Initial Creation**: If external files don't exist, they're created with current configuration
3. **Updates**: Any configuration changes via the UI are automatically saved to external files
4. **Persistence**: External files persist across application restarts

## Docker Usage

### Docker Compose Example

```yaml
version: '3.8'
services:
  shiftscheduler:
    build: .
    ports:
      - "5000:5000"
    volumes:
      - ./config:/app/config  # Mount config directory
    environment:
      - ASPNETCORE_ENVIRONMENT=Production
```

### Folder Structure

```
project/
├── docker-compose.yml
├── config/                 # This directory will be created automatically
│   ├── shifts.json        # Persisted shift configurations
│   └── transport.json     # Persisted transport settings
└── ...
```

## Benefits

- **Persistence**: Configuration survives container rebuilds
- **Backup**: Easy to backup/restore configuration by copying JSON files
- **Version Control**: Configuration files can be committed to source control
- **Multiple Environments**: Different config files for different deployments
- **No Data Loss**: UI changes are automatically preserved

## Migration

No migration needed - existing installations will automatically:
1. Create the `config/` directory on next startup
2. Export current configuration to external files
3. Continue using existing settings

## File Format

Configuration files use standard JSON format and can be edited directly if needed. Changes take effect after application restart.

## Nextcloud Calendar Sync

To enable Nextcloud CalDAV sync, populate the `Nextcloud` section in the production `appsettings.json` (not committed to git):

```json
"Nextcloud": {
  "BaseUrl": "https://your-nextcloud-instance.example.com",
  "Username": "your-nextcloud-username",
  "AppPassword": "your-nextcloud-app-password"
}
```

Generate an app password in Nextcloud: **Settings → Security → Devices & sessions → Create new app password**.