Log Engine

Log Engine is a flexible and extensible logging module for Dart and Flutter applications. It provides a simple interface for logging messages at various levels and supports multiple output targets such as the console and files.

Features

• Log messages at different levels: debug, info, warning, error, fatal.
• Easily switch log output targets (console, file).
• Configure log levels to filter messages.
• Customizable log output implementations.

Installation

Add the following dependency to your pubspec.yaml file:

dependencies:
  log_engine:
    path: path/to/log_engine

Usage

Quick Start Here's an example of how to use the Log Engine in a Flutter or Dart application

mport 'package:log_engine/log_engine.dart';

void main() {
  final logger = Logger();

  // Set the log output to console
  logger.setOutput(ConsoleLogOutput());

  // Set the log level to info
  logger.setLogLevel(LogLevel.info);

  // Log messages
  logger.logInfo('This is an info message');
  logger.logError('This is an error message', exception: Exception('Sample exception'));

  // Set the log output to a file
  logger.setOutput(FileLogOutput('logs/app.log'));

  // Log messages to the file
  logger.logDebug('This is a debug message');
}

Log Levels The LogLevel enum defines the severity of log messages:

• LogLevel.debug
• LogLevel.info
• LogLevel.warning
• LogLevel.error
• LogLevel.fatal

Set the log level to control which messages are output:

logger.setLogLevel(LogLevel.warning);

Log Outputs Log Engine supports multiple log outputs. You can implement your own by extending the LogOutput abstract class.

ConsoleLogOutput Logs messages to the console:

logger.setOutput(ConsoleLogOutput()); 

FileLogOutput Logs messages to a file:

logger.setOutput(FileLogOutput('logs/app.log'));

Extending Log Engine You can create custom log outputs by implementing the LogOutput interface:

class MyCustomLogOutput implements LogOutput {
  @override
  void output(LogLevel level, String message, {Exception? exception, StackTrace? stackTrace}) {
    // Custom implementation
  }
}

Testing Log Engine includes a comprehensive set of unit tests. To run the tests, use the following command:

flutter test 

or, if you are using Dart only:

dart test 

Ensure you have the test package included in your pubspec.yaml under dev_dependencies:

dev_dependencies:
  test: (latest_version)

Project Structure

lib/
  src/
    console_log_output.dart
    file_log_output.dart
    logger.dart
    logger_interface.dart
  log_engine.dart

test/
  logger_interface_test.dart
  logger_test.dart
  file_log_output_test.dart
  console_log_output_test.dart