l

[L]ogger

About

Cross-platform html/io logger with simple API. No need to create a logger object. Just import and use. Simple and w/o boilerplate. Work with native console.

Core API

Example of usage

Example of using the library to display a message in the console.

Key features

Method	Description
[s]	A shout is always displayed
[v1], [v]	Regular message with verbose level 1
[e]	Error message with verbose level 1
[v2], [vv]	Regular message with verbose level 2
[w]	Warning message with verbose level 2
[v3], [vvv]	Regular message with verbose level 3
[i], [<]	Inform message with verbose level 3
[v4], [vvvv]	Regular message with verbose level 4
[d], [<<]	Debug message with verbose level 4
[v5], [vvvvv]	Regular message with verbose level 5
[v6], [vvvvvv]	Regular message with verbose level 6

l.s('shout me');
l.e('error msg');
l.w('warning msg');
l.i('info msg');
l < 'alt info msg';
l.d('debug msg');
l << 'alt debug msg';
l.v('verbose lvl #1');
l.vv('verbose lvl #2');
l.vvv('verbose lvl #3');
l.v4('verbose lvl #4');
l.v5('verbose lvl #5');
l.v6('verbose lvl #6');

Integration capabilities

Method	Description
[listen]	Broadcast stream receiving logs.

// Broadcast stream instantly receiving logs.
l.forEach((log) => print('* ${log.level} : ${log.message}'));

Print handling and customizing

Logger supports fine-tuning with the second argument LogOptions in a capture method. Also, you can handle print and output with l on some function or in a whole app with this simple syntax:

import 'package:l/l.dart';

void main() => l.capture(
      someFunction,
      const LogOptions(
        handlePrint: true,
        printColors: true,
        outputInRelease: false,
        messageFormatting: _messageFormatting,
      ),
    );

Future<void> someFunction() async {
  print('Hello');
  await Future<void>.delayed(const Duration(milliseconds: 150));
  l.d('world');
  await Future<void>.delayed(const Duration(milliseconds: 150));
  l.e('!!!');
}

Object _messageFormatting(Object message, LogLevel logLevel, DateTime now) =>
    '${now.hour}:${now.minute.toString().padLeft(2, '0')} $message';

Handling errors

Flutter

final sourceFlutterError = FlutterError.onError;
FlutterError.onError = (details) {
  l.w(details.exceptionAsString(), details.stack);
  sourceFlutterError?.call(details);
};

Crashlytics

l.where((msg) => msg.level.maybeWhen(
      error: () => true,
      warning: () => true,
      orElse: () => false,
    ))
  .map<String>((msg) => msg.message.toString())
  .listen(FirebaseCrashlytics.instance.log);

Zoned Errors

runZonedGuarded(someFunction, l.e);

Handling uncaught errors

Isolate.current
       ..setErrorsFatal(false)
       ..addErrorListener(
         RawReceivePort(
           (List<dynamic> pair) => // ignore: avoid_types_on_closure_parameters
               l.e(pair.first as Object),
         ).sendPort,
       );

Limitations

• When there is no direct access to the terminal, it works through print.
• !!! PLEASE, DO NOT LOG SENSITIVE INFORMATION !!!

Changelog

Refer to the Changelog to get all release notes.

Maintainers

Plague Fox

Funding

If you want to support the development of our library, there are several ways you can do it:

• Buy me a coffee
• Support on Patreon
• Subscribe through Boosty

We appreciate any form of support, whether it's a financial donation or just a star on GitHub. It helps us to continue developing and improving our library. Thank you for your support!

License

MIT