markdown-tree-parser

A powerful JavaScript library and CLI tool for parsing and manipulating markdown files as tree structures. Built on top of the battle-tested remark/unified ecosystem.

🚀 Features

• 🌳 Tree-based parsing - Treats markdown as manipulable Abstract Syntax Trees (AST)
• ✂️ Section extraction - Extract specific sections with automatic boundary detection
• 🔍 Powerful search - CSS-like selectors and custom search functions
• 📚 Batch processing - Process multiple sections at once
• 🛠️ CLI & Library - Use as a command-line tool or JavaScript library
• 📊 Document analysis - Get statistics and generate table of contents
• 🎯 TypeScript ready - Full type definitions included

📦 Installation

Global Installation (for CLI usage)

# Using npm
npm install -g @kayvan/markdown-tree-parser

# Using pnpm (may require approval for build scripts)
pnpm install -g @kayvan/markdown-tree-parser
pnpm approve-builds -g  # If prompted

# Using yarn
yarn global add @kayvan/markdown-tree-parser

Local Installation (for library usage)

npm install @kayvan/markdown-tree-parser

🔧 CLI Usage

After global installation, use the md-tree command:

List all headings

md-tree list README.md
md-tree list README.md --format json

Extract specific sections

# Extract one section
md-tree extract README.md "Installation"

# Extract to a file
md-tree extract README.md "Installation" --output ./sections

Extract all sections at a level

# Extract all level-2 sections
md-tree extract-all README.md 2

# Extract to separate files
md-tree extract-all README.md 2 --output ./sections

Show document structure

md-tree tree README.md

Search with CSS-like selectors

# Find all level-2 headings
md-tree search README.md "heading[depth=2]"

# Find all links
md-tree search README.md "link"

Document statistics

md-tree stats README.md

Check links

md-tree check-links README.md
md-tree check-links README.md --recursive

Generate table of contents

md-tree toc README.md --max-level 3

Complete CLI options

md-tree help

📚 Library Usage

Basic Usage

import { MarkdownTreeParser } from 'markdown-tree-parser';

const parser = new MarkdownTreeParser();

// Parse markdown into AST
const markdown = `
# My Document
Some content here.

## Section 1
Content for section 1.

## Section 2
Content for section 2.
`;

const tree = await parser.parse(markdown);

// Extract a specific section
const section = parser.extractSection(tree, 'Section 1');
const sectionMarkdown = await parser.stringify(section);

console.log(sectionMarkdown);
// Output:
// ## Section 1
// Content for section 1.

Advanced Usage

import {
  MarkdownTreeParser,
  createParser,
  extractSection,
} from 'markdown-tree-parser';

// Create parser with custom options
const parser = createParser({
  bullet: '-', // Use '-' for lists
  emphasis: '_', // Use '_' for emphasis
  strong: '__', // Use '__' for strong
});

// Extract all sections at level 2
const tree = await parser.parse(markdown);
const sections = parser.extractAllSections(tree, 2);

sections.forEach(async (section, index) => {
  const heading = parser.getHeadingText(section.heading);
  const content = await parser.stringify(section.tree);
  console.log(`Section ${index + 1}: ${heading}`);
  console.log(content);
});

// Use convenience functions
const sectionMarkdown = await extractSection(markdown, 'Installation');

Search and Manipulation

// CSS-like selectors
const headings = parser.selectAll(tree, 'heading[depth=2]');
const links = parser.selectAll(tree, 'link');
const codeBlocks = parser.selectAll(tree, 'code');

// Custom search
const customNode = parser.findNode(tree, (node) => {
  return node.type === 'heading' && parser.getHeadingText(node).includes('API');
});

// Transform content
parser.transform(tree, (node) => {
  if (node.type === 'heading' && node.depth === 1) {
    node.depth = 2; // Convert h1 to h2
  }
});

// Get document statistics
const stats = parser.getStats(tree);
console.log(
  `Document has ${stats.wordCount} words and ${stats.headings.total} headings`
);

// Generate table of contents
const toc = parser.generateTableOfContents(tree, 3);
console.log(toc);

Working with Files

import fs from 'fs/promises';

// Read and process a file
const content = await fs.readFile('README.md', 'utf-8');
const tree = await parser.parse(content);

// Extract all sections and save to files
const sections = parser.extractAllSections(tree, 2);

for (let i = 0; i < sections.length; i++) {
  const section = sections[i];
  const filename = `section-${i + 1}.md`;
  const markdown = await parser.stringify(section.tree);
  await fs.writeFile(filename, markdown);
}

🎯 Use Cases

• 📖 Documentation Management - Split large docs into manageable sections
• 🌐 Static Site Generation - Process markdown for blogs and websites
• 📝 Content Organization - Restructure and reorganize markdown content
• 🔍 Content Analysis - Analyze document structure and extract insights
• 📋 Documentation Tools - Build custom documentation processing tools
• 🚀 Content Migration - Extract and transform content between formats

🏗️ API Reference

MarkdownTreeParser

Constructor

new MarkdownTreeParser((options = {}));

Methods

• parse(markdown) - Parse markdown into AST
• stringify(tree) - Convert AST back to markdown
• extractSection(tree, headingText, level?) - Extract specific section
• extractAllSections(tree, level) - Extract all sections at level
• select(tree, selector) - Find first node matching CSS selector
• selectAll(tree, selector) - Find all nodes matching CSS selector
• findNode(tree, condition) - Find node with custom condition
• getHeadingText(headingNode) - Get text content of heading
• getHeadingsList(tree) - Get all headings with metadata
• getStats(tree) - Get document statistics
• generateTableOfContents(tree, maxLevel) - Generate TOC
• transform(tree, visitor) - Transform tree with visitor function

Convenience Functions

• createParser(options) - Create new parser instance
• extractSection(markdown, sectionName, options) - Quick section extraction
• getHeadings(markdown, options) - Quick heading extraction
• generateTOC(markdown, maxLevel, options) - Quick TOC generation

🔗 CSS-Like Selectors

The library supports powerful CSS-like selectors for searching:

// Element selectors
parser.selectAll(tree, 'heading'); // All headings
parser.selectAll(tree, 'paragraph'); // All paragraphs
parser.selectAll(tree, 'link'); // All links

// Attribute selectors
parser.selectAll(tree, 'heading[depth=1]'); // H1 headings
parser.selectAll(tree, 'heading[depth=2]'); // H2 headings
parser.selectAll(tree, 'link[url*="github"]'); // Links containing "github"

// Pseudo selectors
parser.selectAll(tree, ':first-child'); // First child elements
parser.selectAll(tree, ':last-child'); // Last child elements

🧪 Testing

# Run tests
npm test

# Test CLI
npm run test:cli

# Run examples
npm run example

🔧 Development

Prerequisites

• Node.js 18+
• npm

Setup

# Clone the repository
git clone https://github.com/ksylvan/markdown-tree-parser.git
cd markdown-tree-parser

# Install dependencies
npm install

# Run tests
npm test

# Run linting
npm run lint

# Format code
npm run format

# Test CLI functionality
npm run test:cli

CI/CD

This project uses GitHub Actions for continuous integration. The workflow automatically:

• Tests against Node.js versions 18.x, 20.x, and 22.x
• Runs linting with ESLint
• Executes the full test suite
• Tests CLI functionality
• Verifies the package can be published

The CI badge in the README shows the current build status and links to the Actions page.

🤝 Contributing

Contributions are welcome! Please read our Contributing Guide for details.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

📄 License

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

🙏 Acknowledgments

Built on top of the excellent unified ecosystem:

• remark - Markdown processing
• mdast - Markdown AST specification
• unist - Universal syntax tree utilities

📞 Support

• 📖 Documentation
• 🐛 Issue Tracker
• 💬 Discussions

Made with ❤️ by Kayvan Sylvan