Markdown Renderer for GitHub

Description

Markdown Renderer for GitHub transforms your WordPress content with beautiful GitHub Flavored Markdown (GFM) rendering. Perfect for technical blogs, documentation sites, and any content that needs professional code presentation.

Key Features:

🎨 Beautiful Syntax Highlighting
* Powered by Shiki – the same syntax highlighter used by VS Code
* Support for 100+ programming languages
* Multiple beautiful themes (GitHub Light/Dark, VS Code themes, and more)
* Automatic language detection

📊 Mermaid Diagram Support
* Create flowcharts, sequence diagrams, and more
* Professional diagram rendering
* Interactive zoom functionality
* Error handling with user-friendly messages

📈 Chart.js Chart Support
* Create line, bar, pie, doughnut, and more chart types
* 8 chart types including scatter, bubble, radar, and Polar Area
* Simple JSON configuration in “`chart fenced code blocks
* Responsive and interactive charts

✨ GitHub Flavored Markdown
* Tables, task lists, strikethrough
* Automatic URL linking
* Footnotes support
* 100% compatible with GitHub markdown

📋 Copy Button Feature
* One-click code copying
* GitHub-style user experience
* Full accessibility support
* Mobile-friendly design

⚡ Performance Optimized
* Asset lazy loading
* Minimal performance impact
* CDN-friendly architecture
* Optimized for WordPress

🌍 Developer Friendly
* Clean, semantic HTML output
* Extensive hooks and filters
* Translation ready (i18n)
* WordPress coding standards

Perfect for:
* Technical blogs and tutorials
* Documentation websites
* Code portfolios
* Educational content
* API documentation
* Developer resources

Technical Requirements

• WordPress 6.8 or higher
• PHP 8.2 or higher
• Modern browser with JavaScript enabled
• Recommended: 128MB+ PHP memory limit
• Recommended: gzip or Brotli compression enabled for static JavaScript on your web server

Why server compression matters:
The syntax-highlighting and diagram libraries are large when uncompressed (Shiki ~2.35 MB, Mermaid ~3.2 MB) but shrink dramatically when delivered with gzip or Brotli (Shiki ~302 KB, Mermaid ~908 KB). For the best front-end performance, ensure your web server compresses static JavaScript (for example mod_deflate/mod_brotli on Apache, or the gzip/brotli directives on nginx). Most managed hosts and CDNs enable this by default. The plugin adds a Tools → Site Health check that reports whether these bundles are actually being served compressed.

Support

For support, please visit the WordPress.org support forum for this plugin. Our team actively monitors and responds to support requests.

Before posting a support request:
* Check the FAQ section above for common questions
* Ensure you’re using the latest version of the plugin
* Include your WordPress and PHP versions in your support request

Feature Requests:
We welcome feature suggestions! Please post them in the support forum with detailed descriptions of your use case.

Source Code

This plugin uses build tools for development efficiency.

Compressed File Source Code:
* build/index.js: WordPress Block Editor integration code
* Source: blocks/markdown/src/ folder
* Build: npm run build
* assets/libs/shiki/shiki.min.js: Shiki syntax highlighter (self-contained bundle, no CDN)
* Source: scripts/vendor/shiki-entry.mjs
* Build: npm run vendor:shiki

Source Code Access:
* GitHub Repository: https://github.com/my-biz-dev/markdown-renderer-for-github
* License: GPL v2 or later
* Development Branch: main

Build Instructions:
1. Install Node.js 18+
2. Install dependencies with npm install
3. Build with npm run build
4. Run tests with npm run test

Developer Resources:
* Development Environment Setup: See CLAUDE.md and docs/DEVELOPMENT.md
* Contributing: See CONTRIBUTING.md
* Build Process Details: See BUILD.md

Third Party Services

This plugin operates entirely self-contained and does NOT use any external third-party services.

Complete Local Operation:
* All JavaScript libraries are bundled locally within the plugin
* Shiki syntax highlighter – served from your WordPress installation (no CDN)
* Mermaid diagram renderer – served from your WordPress installation (no CDN)
* Chart.js chart renderer – served from your WordPress installation (no CDN)
* No external API calls or network requests are made

Privacy & Security Benefits:
* No data is transmitted to external servers
* No tracking, analytics, or data collection
* No external dependencies that could compromise your site
* GDPR compliant by design
* Works offline and in closed networks

All functionality is fully self-contained within your WordPress installation with no external service dependencies.

Privacy

This plugin does not collect any personal data. All processing is done locally on your server.

Credits

• Syntax highlighting: Shiki
• Diagram rendering: Mermaid
• Chart rendering: Chart.js
• Markdown parsing: markdown-it

Developer Information

This section provides essential information for developers who want to extend or customize the plugin.

For complete API documentation, architecture diagrams, and customization examples, see:
Developer Documentation on GitHub

Available Hooks and Filters

Actions:

• gfmr_metadata_saved – Fired when code block metadata is saved
  • Parameters: $post_id (int), $metadata (array)
  • Use case: Sync metadata with external services, logging

Filters:

• gfmr_metadata_get_metadata – Filter retrieved metadata before use

  • Parameters: $metadata (array), $post_id (int)
  • Use case: Custom language detection, metadata modification

• gfmr_schema_data – Filter Schema.org JSON-LD data before output

  • Parameters: $schema (array), $post (WP_Post)
  • Use case: Add custom schema properties, author profiles

PHP Constants

• GFMR_PLUGIN_FILE – Plugin main file path
• GFMR_SLUG – Plugin slug (‘markdown-renderer-for-github’)
• GFMR_URI – Plugin URL
• GFMR_PATH – Plugin directory path
• GFMR_PLUGIN_PATH – Plugin directory name (relative)
• GFMR_PLUGIN_BASENAME – Plugin basename
• GFMR_ASSETS_PATH – Assets directory URL

JavaScript Global Objects

• wpGfmConfig – Plugin configuration object
• wpGfmRenderer – Core rendering API (processCodeBlocks, renderContent, initialize)
• wpGfmHighlighter – Highlighter wrapper instance
• wpGfmShikiHighlighter – Actual Shiki highlighter instance
• wpGfmUnifiedHighlight(code, lang, options) – Unified highlight function
• wpGfmSwitchTheme(newTheme) – Theme switching function (‘light’, ‘dark’, ‘system’)
• wpGfmRenderDiagram(content, element, options) – Diagram rendering function

Settings Option

Option name: gfmr_theme_settings

Available keys:

• theme – Theme setting (‘light’, ‘dark’, ‘system’)
• schema_enabled – Enable Schema.org JSON-LD output (bool)
• schema_auto_detect_type – Auto-detect article type (bool)
• schema_include_author – Include author in schema (bool)
• schema_include_publisher – Include publisher in schema (bool)

Plugin Development

This plugin follows WordPress coding standards and provides clean, semantic HTML output.

Detailed Documentation:

For complete documentation including full API reference with code examples, architecture diagrams (Mermaid), step-by-step customization guides, and CSS class reference, visit:

GitHub Developer Documentation