l 3.3.0-dev

Cross-platform html/io Logger library with simple API. Manipulate with native and web console. Support ascii colorize output.

[L]ogger

About

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

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Core API

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 second argument LogOptions in l.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';

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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,
       );

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Output example

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Limitations

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

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Changelog

Refer to the Changelog to get all release notes.

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Maintainers

Plague Fox

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License

WTFPL

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Tags

logger, log, logs, logging, logging-library, cross-platform, io, html