YALP - Yet Another Logging Package

Introduction

YALP is a logging package for Dart and Flutter that provides a simple and flexible way to log messages in your applications.

Features

• Easy to use API
• Support for different log levels
• Contextual logging
• Tagging
• Builtin UI

Installation

To use YALP in your Dart project, add the following dependency to your pubspec.yaml file:

dependencies:
  yalp_core: ^1.0.0
  yalp_isar_storage: ^1.0.0 # For persisting the logs
  yalp_flutter: ^1.0.0 # Builtin UI

Packages

Package	Description
yalp_core
yalp_isar_storage
yalp_flutter

Usage

Setup

To use the Logger you need to setup and initialize the Logger. Add the following lines of code in your app startup.

import 'package:yalp_core/yalp_core.dart';

...

await Logger.root.init(IsarLogStorage(), KeepAll());

This initializes the log storage and applies the provided retention policy.

Logging

To log something you can either use Logger.root or create a new Logger instance. The Logger has a method for each of the following logging level: trace, debug, info, warning, error, fatal.

Logger.root.info('Something happend');

or

final logger = Logger();
logger.info('Something happend');

Each log method accepts the following optional arguments:

Argument	Description
Object? error	The exception or error object.
StrackTrace? stackTrace	Stacktrace of the exception or custom stacktrace.
String? tag	Custom tag to group or mark a log message
LogContext? context	details in the next part

Contextual logging

The base LogContext gives you the option to specify the className and functionName which should be saved in the log. If none is provided both names are extracted from the stackTrace.

The more interesting LogContext is the TrackedLogContext which enables you to group and associate logs. Every time you create a new TrackedLogContext a new v4 UUID is generated and stored in the context and later also in each log entry itself.

Each TrackedLogContext can also have a parent TrackedLogContext. This enables you to group logs with arbitrary nesting. This is pretty usefull when logging parallel methods.

final logger = Logger();

// Uses current stacktrace to extract class and function name 
final lc1 = LogContext();
logger.info('Something happend', context: lc1);

// Class and function names are provided in the constructor
final lc2 = LogContext(className: 'Test', functionName: 'run');
final logger.info('Something happend', context: lc2);

// Single tracked context
final lc3 = LogContext.tracked();
logger.info('Something happend', context: lc3);
logger.warning('Something could be wrong here', context: lc3);

// Nested tracked contexts
final lc4 = LogContext.tracked();

logger.info('Something happend', context: lc4);

final lc5 = lc4.nested();
logger.warning('Something does not look right', context: lc5);

logger.fatal('Oh no its crashed', context: lc4);

UI

To show the logs you simple import yalp_flutter and use the MaterialLogViewer widget (CupertinoLogViewer coming soon...).