# Log Formats

Zario supports two primary log formats: **Plain Text** (default) and **JSON**. You can switch between these formats using the `json` configuration option.

## Plain Text Format

The plain text format is designed for human readability, making it ideal for development and CLI tools.

### Structure
The default structure of a text log entry is:
```text
[Timestamp] [Prefix] [LEVEL] Message {metadata}
```

- **Timestamp**: Included if `timestamp` is set to `true`. Formatted according to `timestampFormat`.
- **Prefix**: Included if a `prefix` is configured for the logger.
- **LEVEL**: The log level (e.g., INFO, ERROR), optionally colorized.
- **Message**: The main log message.
- **Metadata**: Any additional data objects passed to the log method, serialized as JSON.

### Examples

**Standard Log:**
```text
[2025-01-23 10:22:20] [INFO] Server started on port 3000
```

**With Prefix and Metadata:**
```text
[2025-01-23 10:22:20] [API] [ERROR] Database connection failed {"host":"localhost","port":5432}
```

## JSON Format

The JSON format is structured and machine-readable, making it perfect for production environments and log aggregators like ELK, Datadog, or cloud logging services.

### Structure
Each log entry is a single JSON object on a new line. Unlike some other loggers that nest metadata in a `data` field, Zario **spreads metadata fields into the root of the JSON object** for easier querying.

### Fields
- `level`: The log level string.
- `message`: The log message string.
- `timestamp`: The ISO 8601 timestamp (included if `timestamp: true`).
- `prefix`: The logger prefix (included if configured).
- `...metadata`: Any key-value pairs from the metadata object are included at the root level.

### Examples

**Basic JSON Log:**
```json
{"level":"info","message":"User logged in","timestamp":"2025-01-23T10:22:20.000Z"}
```

**JSON Log with Metadata:**
```json
{
  "level": "error",
  "message": "Request failed",
  "timestamp": "2025-01-23T10:22:25.000Z",
  "path": "/api/users",
  "status": 500,
  "userId": "12345"
}
```

## Color Support

When `colorize` is enabled (default in development), Zario uses ANSI color codes for console output.

### Environment Detection
Zario automatically detects terminal color support. You can force colors on or off using environment variables:
- `FORCE_COLOR=1`: Force color support.
- `FORCE_COLOR=0`: Disable color support.

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