Logger RS

A Rust-style logger for Dart with colored output, precise file locations, and clean formatting inspired by the Rust compiler.

Installation

dependencies:
  logger_rs: ^2.0.3

Quick Start

import 'package:logger_rs/logger_rs.dart';

void main() {
  Log.d('Debug message');     // Cyan
  Log.i('Info message');      // Green
  Log.w('Warning message');   // Yellow
  Log.e('Error message');     // Red
  Log.f('Fatal message');     // Magenta
  Log.t('Trace message');     // Gray
}

Log Levels

Level	Method	Color	Description
Trace	Log.t()	Gray	Verbose debugging, method entry/exit
Debug	Log.d()	Cyan	Development information
Info	Log.i()	Green	General information
Warning	Log.w()	Yellow	Potential issues
Error	Log.e()	Red	Errors with optional stack traces
Fatal	Log.f()	Magenta	Critical failures

Output Examples

Simple Messages

TRACE: Entering function src/service.dart:10:3

DEBUG: Processing request src/controller.dart:25:5

INFO: Server started on port 8080 src/main.dart:15:3

WARNING: Deprecated API usage
  --> src/legacy.dart:67:9
   |
   └─

ERROR: Connection failed
  --> src/database.dart:45:12
   |
   └─

CRITICAL: System out of memory
  --> src/core.dart:112:7
   |
   └─

With Error and Stack Trace

try {
  await riskyOperation();
} catch (error, stackTrace) {
  Log.e('Operation failed', error: error, stackTrace: stackTrace);
}

ERROR: Operation failed
  --> src/service.dart:45:12
   |
   = error: SocketException: Connection refused
 1 | #0  Service.call (src/service.dart:45:12)
 2 | #1  App.run (src/app.dart:23:5)
   └─

With Objects (JSON)

Log.i({'user': 'john', 'action': 'login'});

INFO: src/auth.dart:15:3
   |
   ┌─
{
  "user": "john",
  "action": "login"
}
   └─

Tag Logging (Advanced)

Group related logs across your application and export them for debugging or AI analysis.

Basic Usage

// Tag logs throughout your code
Log.tag('auth', 'User pressed login');
Log.tag('auth', 'Validating credentials', level: Level.INFO);
Log.tag('auth', {'email': '[e-mail]'});

// Export when needed
Log.export('auth');

Conditional Export

// Export only if errors occurred
Log.export('auth', onlyOnError: true);

// Export based on custom condition
Log.export('auth', export: isDebugMode);

Export Output

When you call Log.export('auth'), the output is Markdown formatted for AI analysis:

# Tag: auth
════════════════════════════════════════════════════════════════════════════════
> **Tag:** `auth`
> **Generated:** 2024-01-30 12:30:45
> **Entries:** 4 | **Errors:** 1

## Summary
- **ERROR**: 1
- **INFO**: 2
- **DEBUG**: 1

## Timeline

### 12:30:45.001 🔵 [DEBUG] auth_page.dart:23:7
User pressed login

### 12:30:45.015 🟢 [INFO] auth_controller.dart:45:9
Validating credentials

### 12:30:45.050 🔵 [DEBUG] auth_service.dart:32:7
```json
{
  "email": "[e-mail]"
}

12:30:46.200 🔴 ERROR auth_controller.dart:52:11

Login failed: Invalid credentials

Stack Trace

#0  AuthService.authenticate (auth_service.dart:45:5)
#1  AuthController.login (auth_controller.dart:52:11)

---

Exported by logger_rs

════════════════════════════

Copy the content between the separators and paste it into your LLM.

Save to File

export returns the formatted Markdown string, so you can save it to a file:

final markdown = Log.export('auth');
if (markdown != null) {
  File('debug_auth.md').writeAsStringSync(markdown);
}

// Export all tags to files
final allLogs = Log.exportAll();
for (final entry in allLogs.entries) {
  File('${entry.key}_log.md').writeAsStringSync(entry.value);
}

Tag API

Method	Returns	Description
Log.tag(name, msg)	void	Add log to tag
Log.export(name)	String?	Export to console and return markdown
Log.exportAll()	Map<String, String>	Export all tags, return map of results
Log.clear(name)	void	Clear tag without exporting
Log.clearAll()	void	Clear all tags
Log.hasTag(name)	bool	Check if tag exists
Log.hasErrors(name)	bool	Check if tag has errors
Log.entryCount(name)	int	Get entry count

Tags are automatically removed in release builds (zero overhead).

Platform Support

Works on all Dart platforms with automatic color support:

• Flutter (iOS, Android, Web, Desktop)
• Dart VM / Native
• Web (WASM compatible)

License

MIT License - see LICENSE for details.

Author

JhonaCode - @JhonaCodes

Libraries

logger_rs

A beautiful Rust-style logger for Dart.