Another logger

example.dart

class MyService {
  final _log = Logger('MyService');
  
  void init() {
    try {
      // operation
      _log("initialized"); 
    } catch(e, stackTrace){
      _log.e("init() error", e, stackTrace);
    }
  }
}

logger.dart

import 'package:firebase_crashlytics/firebase_crashlytics.dart';
import 'package:flutter/foundation.dart';

void setupLogger() {
  Logger.registerChannel(DebugPrintLoggerChannel());
  Logger.registerChannel(CrashlyticsLoggerChannel());
}

/// A tagged logging utility with debug / warn / error severity and custom
/// channels
class Logger {
  Logger(this.tag);

  final String tag;

  static final _channels = <LoggerChannel>{};

  /// Adds a channel to the logging utility
  static void registerChannel(LoggerChannel channel) => _channels.add(channel);

  void d(String message) {
    for (final channel in _channels) {
      channel.d(tag, message);
    }
  }

  void call(String message) => d(message);

  void e(String message, dynamic error, [StackTrace? stackTrace]) {
    for (final channel in _channels) {
      channel.e(tag, message, error, stackTrace);
    }
  }

  void w(String message) {
    for (final channel in _channels) {
      channel.w(tag, message);
    }
  }
}

abstract class LoggerChannel {
  /// Handle a debug log event
  void d(String tag, String message) {}

  /// Handle a warning log event
  void w(String tag, String message) {}

  /// Handle an error log event
  void e(String tag, String message, dynamic error, StackTrace? stackTrace) {}
}

/// Outputs all log to console via [debugPrint]
class DebugPrintLoggerChannel implements LoggerChannel {
  @override
  void d(String tag, String message) {
    debugPrint('D [$tag]: \t $message');
  }

  @override
  void e(String tag, String message, dynamic error, StackTrace? stackTrace) {
    debugPrint('E [$tag]: \t $message, $error');
  }

  @override
  void w(String tag, String message) {
    debugPrint('W [$tag]: \t $message');
  }
}

class CrashlyticsLoggerChannel implements LoggerChannel {
  FirebaseCrashlytics get _c => FirebaseCrashlytics.instance;

  @override
  void d(String tag, String message) {
    _c.log('D [$tag]: \t $message');
  }

  @override
  void e(String tag, String message, error, StackTrace? stackTrace) {
    _c.log('E [$tag]: \t $message, $error');
  }

  @override
  void w(String tag, String message) {
    _c.log('W [$tag]: \t $message');
  }
}