logger_pro #

A modern, developer-first logger for Dart & Flutter that gets out of your way. It provides beautiful, readable console output with zero-config ANSI colors, while offering powerful features for complex debugging—like performance profiling with millisecond diffs, structured JSON sinks, and unique handlers for inspecting raw data like HEX strings and ANSI terminal sequences.

With zero dependencies and seamless DevTools integration, it's the perfect companion for your next CLI, Flutter app, or server-side project.

Works great for CLI tools, Flutter apps, and test environments. No dependencies.

Platform Support #

✨ Features #

• Zero‑dependency. Pure Dart. Usable in both Dart VM and Flutter.
• Colorful by default. ANSI colors with an AnsiColor enum and a global ansiEnabled switch.
• Readable channels. The name parameter acts like a tag/channel: [network], [auth], etc.
• Timestamps & perf. Use time: true for [HH:mm:ss] or msDiff: true to see deltas between logs.
• Pluggable sinks. Implement LoggerPlus to forward each structured log event (JSON) anywhere.
• Binary‑friendly. logBufHex, logBufChr and logBufAnsi for protocol debugging and terminal control.
• DevTools‑friendly. Uses dev.log under the hood; level, zone, and sequenceNumber are preserved.

📦 Installation #

Add to your pubspec.yaml:

dependencies:
  logger_pro: ^0.0.1

or run this command with Dart :

dart pub add logger_pro

Then import:

import 'package:logger_pro/logger_pro.dart';

🚀 Quick start #

import 'package:logger_pro/logger_pro.dart';

void main() {
  ansiEnabled = true; // Turn off if your console doesn't support ANSI

  logi('App started', name: 'bootstrap');
  logw('Careful here', name: 'config');
  loge('Something failed', name: 'io', error: Exception('disk full'));
  logd('Debug details', name: 'debug');
}

Output (sample):

[bootstrap] App started 
[config] Careful here 
[io] Something failed 
[debug] Debug details

🧪 Sinks (structured logs to anywhere) #

Every log goes through a single global sink if registered. You receive a Map<String, dynamic> (JSON‑ready) with fields like kind, timestamp, message, name, error, etc.

import 'dart:convert';
import 'package:logger_pro/logger_pro.dart';

class JsonSink extends LoggerPlus {
  final encoder = const JsonEncoder.withIndent('  ');
  @override
  void onLog(Map<String, dynamic> event) {
    // Send to a file, HTTP endpoint, analytics pipeline, etc.
    print(encoder.convert(event));
  }
}

void main() {
  registerLogSink(JsonSink());
  logi('Ship it!', name: 'release');
}

Event shape (example):

{
  "kind": "logi",
  "timestamp": "2025-08-17T12:34:56.789012",
  "message": "Ship it!",
  "timePrinted": false,
  "msDiffPrinted": false,
  "timeHHmmss": null,
  "sequenceNumber": null,
  "level": 0,
  "name": "release",
  "zone": null,
  "error": null,
  "stackTrace": null,
  "ansiEnabled": true,
  "color": "green"
}

Unregister the sink when you’re done:

unregisterLogSink();

⏱️ Time #

time: true #

Prefix the message with [HH:mm:ss]:

logi('Tick', time: true, name: 'clock');  // [12:04:33]

msDiff: true #

Show the current time and the delta since the previous log in milliseconds/seconds:

logi('First',  msDiff: true, name: 'perf');
logi('Second', msDiff: true, name: 'perf'); // [HH:mm:ss] [+12.34ms] Second

time and msDiff are mutually exclusive; the logger will assert if both are set.

Colors & channels #

logi('Saved', name: 'db', color: AnsiColor.green);
logw('Retrying', name: 'network', color: AnsiColor.yellow);
loge('Boom', name: 'auth', color: AnsiColor.red);
logd('Trace', name: 'debug', color: AnsiColor.cyan);

Disable colors globally:

ansiEnabled = false;

🔧 Working with buffers #

Hex #

logBufHex([0xDE, 0xAD, 0xBE, 0xEF], name: 'pkt');
// (4 bytes) DE AD BE EF

Chr (ASCII if printable, hex otherwise) #

logBufChr([72, 101, 108, 108, 111, 10], name: 'pkt');
// (6 bytes) H e l l o 0x0A

Raw ANSI escape sequences #

Send terminal control directly (color, cursor movement, clear screen, …):

final redHello = <int>[
  27, 91, 51, 49, 109,         // ESC[31m  -> red
  ...'Hello, ANSI!'.codeUnits,
  27, 91, 48, 109,             // ESC[0m   -> reset
];
logBufAnsi(redHello, name: 'ansi-demo');

Some IDE consoles ignore cursor movement/clear operations. Use a real terminal for full effect.

API overview #

void logi(String message, { bool time, bool msDiff, int? sequenceNumber, int level, String name, Zone? zone, Object? error, StackTrace? stackTrace, AnsiColor? color });
void logw(String message, { ...same params... });
void loge(String message, { ...same params... });
void logd(String message, { ...same params... });

void logBufHex(List<num> buf, { ...same params... });
void logBufChr(List<num> buf, { ...same params... });
void logBufAnsi(List<num> buf, { ...same params... });

void registerLogSink(LoggerPlus sink);
void unregisterLogSink();

bool get ansiEnabled;
set ansiEnabled(bool value);

Kinds : logi, logw, loge, logd, hex, chr, ansi.

🔍 Example project #

A complete example is included under /example showing basic logging, timestamps, diffs, buffers, and ANSI control sequences.

Run it:

dart run example/main.dart

🤝 Contributing #

Issues and pull requests are welcome. If you find a bug or want a feature, open an issue with a clear repro or use‑case.

📄 License #

This project is licensed under the MIT License.