Converts OPML lists to a simple markdown bulleted list with links, ideal for sharing RSS feeds

convert-opml.ts

import { XMLParser } from 'fast-xml-parser';

interface OutlineItem {
  text: string;
  title?: string;
  htmlUrl?: string;
  xmlUrl?: string;
}

function parseOpml(opmlContent: string): OutlineItem[] {
  const parser = new XMLParser({
    ignoreAttributes: false,
    attributeNamePrefix: "@_"
  });

  const jsonObj = parser.parse(opmlContent);
  const outlines = jsonObj.opml?.body?.outline || [];

  // Handle both single outline and array of outlines
  const outlineArray = Array.isArray(outlines) ? outlines : [outlines];

  const items: OutlineItem[] = outlineArray
    .filter(outline => outline["@_type"] === "rss")
    .map(outline => ({
      text: outline["@_text"] || outline["@_title"] || 'Untitled',
      title: outline["@_title"],
      htmlUrl: outline["@_htmlUrl"],
      xmlUrl: outline["@_xmlUrl"]
    }));

  return items;
}

function convertToMarkdown(items: OutlineItem[]): string {
  const lines = items.map(item => {
    const name = item.text || item.title || 'Untitled';
    // Prefer htmlUrl (website) over xmlUrl (RSS feed), fallback to xmlUrl if no htmlUrl
    const url = (item.htmlUrl && item.htmlUrl.trim() !== '') ? item.htmlUrl : item.xmlUrl || '#';
    return `- [${name}](${url})`;
  });

  return lines.join('\n');
}

async function main() {
  const args = process.argv.slice(2);

  if (args.length === 0) {
    console.error('Usage: bun convert-opml.ts <opml-file> [output-file]');
    console.error('Example: bun convert-opml.ts subscriptions.opml links.md');
    process.exit(1);
  }

  const inputFile = args[0];
  const outputFile = args[1] || inputFile?.replace(/\.opml$/i, '.md');

  try {
    const opmlContent = await Bun.file(inputFile as string).text();
    const items = parseOpml(opmlContent);
    const markdown = convertToMarkdown(items);

    await Bun.write(outputFile as string, markdown);
    console.log(`✅ Converted ${items.length} items from ${inputFile} to ${outputFile}`);

  } catch (error) {
    console.error('❌ Error:', error);
    process.exit(1);
  }
}

if (import.meta.main) {
  main();
}