qtlogger

QtLogger Documentation

QtLogger Documentation

A simple yet powerful logging solution for the Qt Framework. QtLogger provides an intuitive and configurable logging system that works seamlessly with existing Qt logging macros (qDebug(), qInfo(), qWarning(), qCritical(), qFatal()).

Key Features

• Zero code changes — works with existing Qt logging macros
• One-line configuration: gQtLogger.configure()
• Flexible pipeline architecture for processing log messages
• Multiple output destinations (console, file, network, system logs)
• Rich formatting options with pattern and JSON formatters
• Category-based and regex filtering
• Asynchronous logging with optional dedicated thread
• Cross-platform: Linux, Windows, macOS, iOS, Android

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Table of Contents

Getting Started

• Getting Started — Installation, integration options, Hello World example, and preprocessor macros

Core Concepts

• Architecture — Understanding the pipeline concept, data flow, handler types, and lifecycle management

Configuration

• Configuration Guide — Fluent API, INI file configuration, and Qt logging rules integration

API Reference

• API Reference — Complete API documentation
  • Core Classes — Logger, LogMessage, context and utilities
  • Pipelines — Pipeline, SimplePipeline, SortedPipeline
  • Sinks — All output destinations (File, Console, Network, Syslog, etc.)
  • Formatters — Pattern, JSON, Pretty, and Qt default formatters
  • Filters — Level, Category, RegExp, and Duplicate filters
  • Attribute Handlers — Custom attributes, AppInfo, HostInfo, SeqNumber

Advanced Topics

• Advanced Usage — Asynchronous logging, thread safety, and creating custom handlers

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Quick Example

#include "qtlogger.h"

int main(int argc, char *argv[])
{
    QCoreApplication app(argc, argv);
    
    gQtLogger.configure();  // That's it!
    
    qDebug() << "It just works!";
    
    return app.exec();
}

For more complex scenarios:

#include "qtlogger.h"

int main(int argc, char *argv[])
{
    QCoreApplication app(argc, argv);

    gQtLogger
        .moveToOwnThread()                 // Asynchronous logging
        .addSeqNumber()
        .pipeline()
            .filterLevel(QtWarningMsg)     // Only warnings and above
            .formatPretty()
            .sendToStdErr(true)            // Colored output
        .end()
        .pipeline()
            .format("%{time} [%{category}] %{type}: %{message}")
            .sendToFile("app.log", 1024 * 1024, 5)
        .end();

    gQtLogger.installMessageHandler();

    qDebug() << "Application started";
    qWarning() << "This is a warning";

    return app.exec();
}

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Requirements

• C++17 compatible compiler
• Qt Framework: Qt 5.9 — Qt 6.10

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License

This project is licensed under the MIT License. See the LICENSE file for details.

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