はてなブログから export した MT ファイルを Markdown に変換する Deno スクリプト

hatena-mt-to-md.ts

import * as path from "https://deno.land/std@v0.100.0/path/mod.ts";

const content = await Deno.readTextFile(Deno.args[0]);
const outDir = Deno.args[1] || "output";
await Deno.mkdir(outDir, { recursive: true });
console.log(`Export to ${outDir}`);

const articles = content.split("AUTHOR: agtn").slice(1);

function parseArticle(
  article: string,
): { title: string; date: string; content: string } {
  const title = (article.match(/^TITLE: (.*)$/m) as any)[1].trim();
  const date = new Date((article.match(/^DATE: (.*)$/m) as any)[1].trim());
  const content = article.split("-----\nBODY:\n")[1].trim();
  return { title, date: date.toISOString(), content };
}

console.log(`${articles.length} articles found.`);
for (const article of articles) {
  const { title, date, content } = parseArticle(article);
  const outFilePath = path.join(
    outDir,
    title.replaceAll("/", "_").replaceAll(" ", "_") + ".md",
  );
  const contentWithFrontmatter = `---
title: "${title}"
date: ${date}
tags: []
---
${content}`;
  await Deno.writeTextFile(outFilePath, contentWithFrontmatter);
}