# DanceLessonsCoach

A Go project demonstrating idiomatic package structure, CLI implementation, and JSON API with Chi router.

## Features

- Greet function with default behavior
- Command-line interface
- JSON API with versioned endpoints
- Chi router integration
- Zerolog for high-performance logging
- Viper for configuration management
- Graceful shutdown with context
- Unit tests
- Go 1.26.1 compatible

## Installation

```bash
# Clone the repository
git clone https://github.com/yourusername/DanceLessonsCoach.git
cd DanceLessonsCoach

# Build and run
go run ./cmd/greet
```

## Optional Configuration

The project supports configuration via YAML file, environment variables, or defaults.
Configuration priority: file > environment variables > defaults

### Configuration File

By default, the application looks for `config.yaml` in the current working directory.

Create a `config.yaml` file:

```yaml
server:
  host: "0.0.0.0"
  port: 8080
shutdown:
  timeout: 30s
```

Then start the server:

```bash
go run ./cmd/server
```

### Custom Config File Path

To specify a custom config file path, use the `DLC_CONFIG_FILE` environment variable:

```bash
# Use a specific config file
export DLC_CONFIG_FILE="/path/to/your/config.yaml"
go run ./cmd/server

# Or in one command
DLC_CONFIG_FILE="/path/to/your/config.yaml" go run ./cmd/server
```

### Environment Variables

You can also configure via environment variables with `DLC_` prefix:

```bash
# Set configuration via environment variables
export DLC_SERVER_HOST="0.0.0.0"
export DLC_SERVER_PORT=8080
export DLC_SHUTDOWN_TIMEOUT=30s

# Start the server
go run ./cmd/server
```

### Configuration Priority

1. **File-based configuration** (highest priority)
2. **Environment variables** (override defaults)
3. **Default values** (lowest priority)

This means if you have both a config file and environment variables, the file takes precedence.

## Usage

### CLI

```bash
# Default greeting
go run ./cmd/greet
# Output: Hello world!

# Custom greeting
go run ./cmd/greet John
# Output: Hello John!
```

### Web Server

```bash
# Start the server
go run ./cmd/server

# Test API endpoints
curl http://localhost:8080/api/health
# Output: {"status":"healthy"}

curl http://localhost:8080/api/v1/greet
# Output: {"message":"Hello world!"}

curl http://localhost:8080/api/v1/greet/John
# Output: {"message":"Hello John!"}
```

## Testing

```bash
# Run all tests
go test ./...

# Run specific package tests
go test ./pkg/greet/
```

## Project Structure

```
DanceLessonsCoach/
├── cmd/
│   ├── greet/              # CLI entry point
│   │   └── main.go
│   └── server/             # Web server entry point
│       └── main.go
├── pkg/
│   ├── config/             # Configuration management
│   │   └── config.go
│   ├── greet/              # Core greet functionality
│   │   ├── api_v1.go       # API v1 handlers
│   │   ├── greet.go        # Core service
│   │   └── greet_test.go    # Unit tests
│   └── server/             # Server implementation
│       └── server.go
├── config.example.yaml     # Configuration template
├── go.mod                   # Go module definition
└── README.md                # Project documentation
```

## License

MIT