Letterboxd API without approval

const LETTERBOXD = 'https://letterboxd.com';
const TMDB = 'https://themoviedb.org';

async function fetchDiary(username) {
  const response = await fetch(`https://proxy.cors.dev/https://letterboxd.com/${username}/rss/`, {
    credentials: 'omit',
  });
  if (!response.ok) {
    throw new Error(`Feed request failed: ${response.headers.get('X-Cors-Error') ?? response.status}`);
  }

  const feed = new DOMParser().parseFromString(await response.text(), 'application/xml');
  if (feed.querySelector('parsererror')) throw new Error('The feed is not valid XML');

  return [...feed.getElementsByTagName('item')]
    .map((item) => {
      const field = (namespace, name) => item.getElementsByTagNameNS(namespace, name)[0]?.textContent ?? '';
      const description = item.getElementsByTagName('description')[0]?.textContent ?? '';
      const poster = new DOMParser().parseFromString(description, 'text/html').querySelector('img');

      return {
        film: field(LETTERBOXD, 'filmTitle'),
        year: Number(field(LETTERBOXD, 'filmYear')) || null,
        rating: Number(field(LETTERBOXD, 'memberRating')) || null,
        watched: field(LETTERBOXD, 'watchedDate'),
        rewatch: field(LETTERBOXD, 'rewatch') === 'Yes',
        liked: field(LETTERBOXD, 'memberLike') === 'Yes',
        tmdbId: field(TMDB, 'movieId'),
        url: item.getElementsByTagName('link')[0]?.textContent ?? '',
        poster: poster?.getAttribute('src') ?? '',
      };
    })
    // Lists share the feed but carry no film fields
    .filter((entry) => entry.film);
}

const diary = await fetchDiary('dave');
console.log(diary.length, diary[0]);

// Markup: <ul id="diary"></ul>
const list = document.querySelector('#diary');

list.replaceChildren(
  ...diary.slice(0, 10).map((entry) => {
    const item = document.createElement('li');
    const link = document.createElement('a');
    const poster = document.createElement('img');
    const stars = entry.rating ? '★'.repeat(Math.floor(entry.rating)) + (entry.rating % 1 ? '½' : '') : 'unrated';

    link.href = entry.url;
    poster.src = entry.poster;
    poster.alt = '';
    poster.width = 70;
    poster.height = 105;
    poster.loading = 'lazy';

    link.append(poster, `${entry.film} (${entry.year ?? '?'})`);
    item.append(link, ` ${stars}, watched ${entry.watched}`);
    return item;
  }),
);

async function fetchFilm(slug) {
  const response = await fetch(`https://proxy.cors.dev/https://letterboxd.com/film/${slug}/`, {
    credentials: 'omit',
  });
  if (!response.ok) {
    throw new Error(`Film page failed: ${response.headers.get('X-Cors-Error') ?? response.status}`);
  }

  const page = new DOMParser().parseFromString(await response.text(), 'text/html');
  const script = page.querySelector('script[type="application/ld+json"]');
  if (!script) throw new Error('No structured data on this page');

  // Letterboxd wraps the JSON-LD in CDATA comments
  const movie = JSON.parse(script.textContent.replace('/* <![CDATA[ */', '').replace('/* ]]> */', ''));
  const meta = (property) => page.querySelector(`meta[property="${property}"]`)?.getAttribute('content') ?? '';

  return {
    title: movie.name,
    year: Number(meta('og:title').match(/\((\d{4})\)$/)?.[1]) || null,
    rating: movie.aggregateRating?.ratingValue ?? null,
    ratings: movie.aggregateRating?.ratingCount ?? 0,
    directors: (movie.director ?? []).map((person) => person.name),
    genres: movie.genre ?? [],
    poster: movie.image,
    backdrop: meta('og:image'),
  };
}

console.log(await fetchFilm('parasite-2019'));