coryd.dev-eleventy/src/posts/2023/drying-up-now-page-templates-eleventy.md

date	title	description	tags
2023-09-03	Drying up now page templates and normalizing data in Eleventy	My now page consists of a number of similar sections — some bespoke text, a number of media grids and lists. The text is repeated once, the lists are easily templated out in Liquid.js and the media grids are all quite similar.	Eleventy development javascript

My now page consists of a number of similar sections — some bespoke text, a number of media grids and lists. The text is repeated once, the lists are easily templated out in Liquid.js and the media grids are all quite similar. Given the prominence of the media grids on the page and the number of them I decided to consolidate them into a single template while also normalizing the data passed into them as best I could.

If you want to skip all the reading, the diff for this is here. There were a few steps to take to get this done. First I went ahead and took an existing media template and went to work reconciling the slight differences between the artist, album, book, tv and movie displays as follows:

{% raw %}

{% if data.size > 0 %}
  {% assign media = data | normalizeMedia %}
  <h2 class="icon--bold m-0 text-xl flex flex-row items-center font-black leading-tight tracking-normal dark:text-white md:text-2xl mt-8 mb-4 [&>svg]:h-7 [&>svg]:w-7">
    {% tablericon icon title %}
    <div class="ml-1">{{ title }}</div>
  </h2>
  <div class="grid gap-2 {% if shape == 'square' %}grid-cols-2 md:grid-cols-4{% else %}grid-cols-3 md:grid-cols-6{% endif %} not-prose">
    {% for item in media limit: count %}
      {% assign alt = item.alt | strip %}
      <a href="{{ item.url | stripUtm }}" title="{{ alt | escape }}">
        <div class="relative block h-full"{% if shape != 'square' %} style="max-width:226px"{% endif %}>
          <div class="absolute left-0 top-0 h-full w-full rounded-lg border border-blue-600 hover:border-blue-800 dark:border-blue-400 dark:hover:border-blue-200 ease-in-out duration-300{% if item.title %} bg-cover-gradient{% endif %}"></div>
          <div class="absolute left-1 bottom-2 drop-shadow-md">
            {% if item.title %}
              <div class="px-1 text-xs font-bold text-white line-clamp-2">{{ item.title }}</div>
            {% endif %}
            {% if item.subtext %}
              <div class="px-1 text-xs text-white line-clamp-2">
                {{ item.subtext }}
              </div>
            {% endif %}
          </div>
          {%- capture size %}{% if shape == 'square' %}225px{% else %}180px{% endif %}{% endcapture -%}
          {% image item.image, alt, 'rounded-lg w-full h-full' %}
        </div>
      </a>
    {% endfor %}
  </div>
{% endif %}

{% endraw %}

We pass in the data to populate the section as data which is passed to the normalizeMedia filter and assigned to a media variable. The normalizeMedia filter does a few things:

module.exports = {
  normalizeMedia: (media) =>
    media.map((item) => {
      let normalized = {
        image: item['image'],
        url: item['url'],
      }
      if (item.type === 'album') {
        normalized['title'] = item['title']
        normalized['alt'] = `${item['title']} by ${item['artist']}`
        normalized['subtext'] = item['artist']
      }
      if (item.type === 'artist') {
        normalized['title'] = item['title']
        normalized['alt'] = `${item['plays']} plays of ${item['title']}`
        normalized['subtext'] = `${item['plays']} plays`
      }
      if (item.type === 'book') normalized['alt'] = item['title']
      if (item.type === 'movie') {
        normalized['title'] = item['title']
        normalized['alt'] = `${item['title']} - ${item['summary']}`
      }
      if (item.type === 'tv') {
        normalized['title'] = item['title']
        normalized['alt'] = `${item['title']} from ${item['name']}`
        normalized['subtext'] = `${item.name} • <strong>${item.episode}</strong>`
      }
      return normalized
    }),
}

Most notably the filter populates an object with the properties known to be common to each media type. Next, it iterates through the media object, checks the type property and mutates the normalized object to include properties specific to the given media type. When returned, our normalized media object can then be iterated through to populate a given media grid. For example, the tv media type maps 'title' to 'title', ${item['title']} from ${item['name']} to 'alt' and so forth. This allows each different media type to be rendered in a grid that supports an object shape like this:

{
  image: string,
  url: string,
  title: string,
  alt: string,
  subtext?: string
}[]

This normalization is made easier by updating the shape of the objects returned by my site's _data files to better align with the object shape required by the normalizeMedia filter. For example (from artists.js):

return {
  title: artist['name'],
  plays: artist['playcount'],
  rank: artist['@attr']['rank'],
  image:
    `https://cdn.coryd.dev/artists/${artist['name'].replace(/\s+/g, '-').toLowerCase()}.jpg` ||
    'https://cdn.coryd.dev/artists/missing-artist.jpg',
  url: artist['mbid']
    ? `https://musicbrainz.org/artist/${artist['mbid']}`
    : `https://musicbrainz.org/search?query=${encodeURI(artist['name'])}&type=artist`,
  type: 'artist',
}

This aligns image and url with the expected defaults in normalizeMedia with the remaining data being mapped inside of the if (item.type === 'artist') condition to align with the expectations of the media-grid.liquid template. Whew.

Now, leveraging this looks like the following:

{% raw %}

{% render "partials/media/grid.liquid", data:artists, icon: "microphone-2", title: "Artists", shape: "square", count: 8, loading: 'eager' %}

{% endraw %}

We use the liquid.js render tag and pass in a number of things: data which accepts the data returned by our artists.js data file, an icon of our choosing, a title of our choosing, a shape (as artist/albums are square and our remaining sets are rendered as vertical images), a count of items to render and the loading strategy to leverage (artists load above the fold and, hence, adopt the 'eager' strategy — the rest are below the fold and default to 'lazy'). My full now.liquid file now looks like this:

{% raw %}

---
layout: main
---
{% render "partials/header.liquid", meta: meta, page: page, nav: nav %}
{{ content }}
{% render "partials/media/grid.liquid", data:artists, icon: "microphone-2", title: "Artists", shape: "square", count: 8, loading: 'eager' %}
{% render "partials/media/grid.liquid", data:albums, icon: "vinyl", title: "Albums", shape: "square", count: 8, loading: 'lazy' %}
{% render "partials/media/album-releases.liquid", albumReleases:albumReleases %}
{% render "partials/media/grid.liquid", data:books, icon: "books", title: "Books", shape: "vertical", count: 6, loading: 'lazy' %}
{% render "partials/now/links.liquid", links:links %}
{% render "partials/media/grid.liquid", data:movies, icon: "movie", title: "Movies", shape: "vertical", count: 6, loading: 'lazy' %}
{% render "partials/media/grid.liquid", data:tv, icon: "device-tv", title: "TV", shape: "vertical", count: 6, loading: 'lazy' %}
<p class="text-xs text-centered pt-6">This is a
  <a href="https://nownownow.com/about">now page</a>, and if you have your own site,
  <a href="https://nownownow.com/about">you should make one too</a>.</p>

{% endraw %}