markdown-it-admonitions

A markdown-it plugin for rendering admonitions (callouts/alerts).

Installation

npm install markdown-it-admonitions

Usage

import MarkdownIt from 'markdown-it';
import admonitionPlugin from 'markdown-it-admonitions';

const md = new MarkdownIt();
md.use(admonitionPlugin);

const result = md.render(`
:::note Custom Title
This is a note admonition with a custom title.
:::

:::warning
This is a warning with the default title.
:::
`);

Syntax

The plugin supports two syntax styles:

Docusaurus Style (default)

:::note Optional Title
Content goes here
:::

Obsidian Style (default)

> [!note] Optional Title
> Content goes here
> More content

Both styles can be enabled or disabled independently via options.

Default Types

• note 📝
• tip 💡
• warning ⚠️
• danger 🚨
• info ℹ️

Options

md.use(admonitionPlugin, {
  // Custom types to register
  types: ['note', 'tip', 'warning', 'danger', 'info', 'custom'],
  
  // Custom emoji icons for types (used when lucideIcons is false)
  icons: {
    custom: '✨',
    note: '📌'
  },
  
  // Use Lucide icons instead of emojis (default: false)
  // See "Lucide Icons" section below for details
  lucideIcons: false,
  
  // Custom marker for Docusaurus style (default is ":")
  marker: ':',
  
  // Enable/disable syntax styles
  // NOTE: At least one must be enabled (default: both true)
  obsidianStyle: true,    // Enable > [!type] syntax (default: true)
  docusaurusStyle: true,  // Enable ::: type syntax (default: true)
  
  // Custom render functions per type
  // IMPORTANT: Both 'open' and 'close' must be provided together for symmetric rendering
  customRenders: {
    custom: {
      open: (tokens, idx, options, env, slf) => {
        tokens[idx].attrJoin('class', 'my-custom-class');
        return slf.renderToken(tokens, idx, options);
      },
      close: (tokens, idx, options, env, slf) => {
        return slf.renderToken(tokens, idx, options);
      }
    }
  }
});

Lucide Icons

The plugin supports Lucide icons via react-icons. When enabled, the plugin renders icon placeholders with data-lucide-icon attributes that you can hydrate with your preferred icon library.

Installation:

npm install react-icons

Enable Lucide icons:

// Use default Lucide icon mappings
md.use(admonitionPlugin, {
  lucideIcons: true
});

// Or provide custom icon name mappings
md.use(admonitionPlugin, {
  lucideIcons: {
    note: 'LuPencil',      // Override default
    tip: 'LuZap',          // Override default
    custom: 'LuSparkles'   // Add new type
  }
});

Default Lucide icon mappings:

| Type | Icon Name | Icon | |------|-----------|------| | note | LuStickyNote | 📄 | | tip | LuLightbulb | 💡 | | warning | LuTriangleAlert | ⚠️ | | danger | LuCircleAlert | 🚨 | | info | LuInfo | ℹ️ |

React example (hydrating icons):

import { useEffect } from 'react';
import * as LucideIcons from 'react-icons/lu';
import { createRoot } from 'react-dom/client';

function hydrateAdmonitionIcons() {
  const iconElements = document.querySelectorAll('[data-lucide-icon]');
  
  iconElements.forEach((el) => {
    const iconName = el.getAttribute('data-lucide-icon');
    const IconComponent = LucideIcons[iconName];
    
    if (IconComponent) {
      const root = createRoot(el);
      root.render(<IconComponent />);
    }
  });
}

// Call after rendering markdown
useEffect(() => {
  hydrateAdmonitionIcons();
}, [markdownContent]);

HTML output with Lucide icons enabled:

<div class="admonition admonition-note">
  <div class="admonition-title">
    <span class="admonition-icon admonition-icon-lucide" data-lucide-icon="LuStickyNote"></span>
    Note
  </div>
  <div class="admonition-content">
    Content here
  </div>
</div>

Symmetry Principles

This plugin enforces symmetry principles to ensure proper HTML structure and consistent behaviour:

• Render Function Pairs: Custom render functions must provide both open and close together. Providing only one will result in a validation error.
• Syntax Styles: At least one of obsidianStyle or docusaurusStyle must be enabled. Both are enabled by default.
• Token Structure: Every opening token has a corresponding closing token with balanced nesting levels.

// ✅ Correct: Both open and close provided
customRenders: {
  note: {
    open: (tokens, idx, options, env, slf) => '<div class="custom">',
    close: (tokens, idx, options, env, slf) => '</div>'
  }
}

// ❌ Invalid: Only open provided (will throw TypeError)
customRenders: {
  note: {
    open: (tokens, idx, options, env, slf) => '<div class="custom">'
  }
}

Styling

The package includes default CSS files with attractive styling for all admonition types. Two versions are available:

• admonitions.css - Full version with comments and formatting (recommended for development)
• admonitions.min.css - Minified version for production use

In HTML

<!-- Development -->
<link rel="stylesheet" href="node_modules/markdown-it-admonitions/admonitions.css">

<!-- Production -->
<link rel="stylesheet" href="node_modules/markdown-it-admonitions/admonitions.min.css">

In JavaScript/TypeScript

// Development
import 'markdown-it-admonitions/admonitions.css';

// Production
import 'markdown-it-admonitions/admonitions.min.css';

Features

The default stylesheet includes:

• Modern, clean design with subtle shadows and borders
• Unique colour schemes for each admonition type:
  • Note: Blue theme
  • Tip: Green theme
  • Info: Cyan theme
  • Warning: Orange theme
  • Danger: Red theme
• Automatic dark mode support via prefers-color-scheme
• Responsive design for mobile devices
• Print-friendly styles
• Proper spacing for nested content (lists, code blocks, etc.)

Demo

You can preview all admonition styles by opening demo.html in your browser. The demo includes:

• All five default admonition types
• Examples with various content types (lists, code blocks, nested elements)
• A theme toggle button to test dark mode

Customisation

You can override the default styles by adding your own CSS rules:

/* Example: Custom styling for note admonitions */
.admonition-note {
  border-left-color: #0066cc;
}

.admonition-note .admonition-title {
  background-colour: #e6f2ff;
  colour: #0066cc;
}

TypeScript

The plugin is written in TypeScript and includes full type definitions:

import type { AdmonitionPluginOptions } from 'markdown-it-admonitions';

const options: AdmonitionPluginOptions = {
  types: ['note', 'warning'],
  icons: {
    note: '📝'
  }
};

Development

# Install dependencies
npm install

# Build the package (includes CSS minification)
npm run build

# Build just the CSS (generates minified version)
npm run build:css

# Watch mode for development
npm run dev

Working with CSS

The minified CSS file (admonitions.min.css) is automatically generated from the source file (admonitions.css) during the build process.

Important: Only edit admonitions.css. The minified version is auto-generated and tracked in .gitignore.

When you make changes to admonitions.css:

1. Edit the source CSS file
2. Run npm run build:css to regenerate the minified version (or npm run build for full build)
3. The minified version will be automatically created for distribution

License

MIT