@domternal/extension-markdown

Bidirectional Markdown for the Domternal editor: parse GitHub-flavored Markdown into the document and serialize the document back to Markdown, covering the full Notion-style schema.

• Import: insertMarkdown / setMarkdownContent commands, plus automatic conversion of Markdown-looking plain-text pastes (opt-out).
• Export: getMarkdown(editor) and a downloadMarkdown helper, with a warning channel for anything Markdown cannot express (alignment, colors, merged table cells).
• Headless: parseMarkdown / serializeMarkdown work against any schema without an editor instance.
• Coverage: headings, lists (bullet, ordered with start, GFM task lists), blockquotes, fenced code with language, tables with column alignment, images, links and autolinks, bold/italic/strike/inline code, hard breaks, LaTeX math ($...$, $$ blocks), emoji glyphs.

Links

Website    •    Documentation    •    Live examples

Install

pnpm add @domternal/extension-markdown

@domternal/core and @domternal/pm are peer dependencies.

Usage

import { Editor } from '@domternal/core';
import { Markdown, getMarkdown, downloadMarkdown } from '@domternal/extension-markdown';

const editor = new Editor({
  extensions: [/* your extensions */, Markdown],
});

// Import
editor.commands.insertMarkdown('## Hello\n\n- [x] done\n- [ ] open');
editor.commands.setMarkdownContent('# Fresh document');

// Export
const { markdown, warnings } = getMarkdown(editor);
downloadMarkdown(editor, 'notes.md');

Markdown-looking plain-text pastes convert automatically. Pastes that carry an HTML flavor, plain prose, and pastes into code blocks are never touched. Disable with Markdown.configure({ paste: false }).

Options

| Option | Default | Description | | --- | --- | --- | | paste | true | Convert Markdown-looking plain-text pastes into rich content. | | tightLists | true | Serialize lists without blank lines between items. | | specs | null | Extra or replacement Markdown mappings for custom nodes and marks. |

Headless usage

import { parseMarkdown, serializeMarkdown } from '@domternal/extension-markdown';

const doc = parseMarkdown('# Title', schema);
const { markdown, warnings } = serializeMarkdown(doc);

Custom nodes without a mapping degrade gracefully: content is preserved as plain text and a warning is reported instead of failing. Custom mappings plug in via Markdown.configure({ specs }) or the specs option of serializeMarkdown.

Fidelity notes

Markdown cannot express everything the editor can. The serializer keeps the content and reports a warning for: text alignment and line height, text and background colors, underline, merged table cells, multi-block table cells, image resize dimensions, toggle (details) structure, and mentions. Round trips of the supported subset are exact and covered by tests.

License

MIT