MarkPaste

MarkPaste is an isomorphic tool that converts rich text to Markdown. It works seamlessly in both the browser as a web application and in Node.js as a library.

Features

• Isomorphic Core: The same robust conversion logic runs in modern browsers and Node.js.
• Rich Text to Markdown: Convert rich text from any source into clean, readable Markdown.
• Multiple Converters: Choose between Turndown for standard conversion or Pandoc (via WASM) for advanced features.
• HTML Cleaning: Optional sanitization to strip unnecessary tags and attributes while preserving structure.
• Web UI: A polished, responsive interface with live HTML preview, syntax highlighting, and dark mode.

Usage

Web Application

1. Open the app: Run locally or host the index.html.
2. Paste: Copy rich text from a webpage or document and paste it into the input area.
3. Get Markdown: View the generated Markdown from multiple converters simultaneously.
4. Copy: Click to copy the Markdown to your clipboard.

Node.js Library

MarkPaste can be used programmatically in Node.js environments. It uses linkedom to provide a lightweight DOM implementation for the conversion logic.

import {convert} from './src/index.js';

const html = '<h1>Hello World</h1><p>This is <b>bold</b> text.</p>';

// Basic usage (defaults to Turndown)
const markdown = await convert(html);
console.log(markdown);

// Using Pandoc
const pandocMarkdown = await convert(html, {converter: 'pandoc'});
console.log(pandocMarkdown);

// Disabling HTML cleaning
const rawMarkdown = await convert(html, {clean: false});

Development

To run MarkPaste locally:

1. Clone & Install:

   git clone https://github.com/paulirish/markpaste.git
   cd markpaste
   pnpm install

2. Start the Web UI:

   pnpm start

   Access the application at http://localhost:7025.

Testing

The project uses a dual-testing strategy:

• Node.js tests: Unit tests for isomorphic modules (pnpm test:node).
• Playwright tests: End-to-end browser testing (pnpm test:web).

Run all tests with:

pnpm test

Pandoc WASM

The pandoc.wasm and pandoc.js files used in this project originate from the haskell-wasm/pandoc-wasm project. Since GitHub Actions artifacts are cleaned up after ~90 days and the upstream repository hadn't run its CI recently, a fork was created to generate fresh build artifacts. The files in this project were obtained from that fork's GitHub Actions build artifacts.

License

This project is licensed under the Apache License 2.0. See LICENSE for details.