logd_html

Modern HTML5 log rendering, dynamic dark/light stylesheet, and file handler satellite package for logd.

Features

• Modern HTML5 Output: Renders structured, browser-ready log documents with level badges, metadata blocks, and collapsible stack traces.
• Dynamic Dark/Light Themes: Built-in CSS system supporting automatic system preferences (prefers-color-scheme) and custom stylesheet injection via HtmlStylesheet.
• Asynchronous File Handling: Background worker isolate offloading via HtmlFileHandler.async().
• Isolate-Safe Components: Compatible with standard isolate pipelines and cross-isolate handlers.

Installation

Add logd_html to your pubspec.yaml:

dependencies:
  logd: ^latest_version
  logd_html: ^latest_version

Quick Start

import 'package:logd/logd.dart';
import 'package:logd_html/logd_html.dart';

void main() async {
  // Configure a logger to write beautiful HTML logs in the background
  final handler = HtmlFileHandler.async(
    path: 'logs/app_logs.html',
    title: 'My Application Logs',
  );

  Logger.configure(
    'html_demo',
    handlers: [handler],
  );

  final logger = Logger.get('html_demo');
  logger.info(
    'Application started successfully.',
    context: {'version': '1.0.0', 'environment': 'production'},
  );

  try {
    throw StateError('Simulated database connection failure');
  } catch (e, stackTrace) {
    logger.error(
      'Failed to connect to database',
      error: e,
      stackTrace: stackTrace,
    );
  }

  await handler.dispose();
}

Custom Stylesheets

Customize typography, colors, padding, and layout by providing a custom HtmlStylesheet:

final customStylesheet = DefaultHtmlStylesheet().copyWith(
  fontFamily: 'Fira Code, monospace',
  fontSize: '13px',
);

final handler = HtmlFileHandler(
  path: 'logs/custom.html',
  formatter: HtmlFormatter(
    title: 'Custom Styled Logs',
    stylesheet: customStylesheet,
  ),
);

Migration from logd <=0.9.7

Starting with logd v0.10.0, all legacy HTML shims (HtmlEncoder, HtmlFileHandler, HtmlFormatter, HtmlStylesheet) have been permanently removed from core package:logd.

• On logd >=0.10.0: Simply import package:logd_html/logd_html.dart. No hide clauses are required.
• On logd 0.9.7: If upgrading gradually, hide the legacy shims (import 'package:logd/logd.dart' hide HtmlEncoder...).
• For detailed instructions, see the Migration Guide.