Marking up a search result list with HTML5 semantics

Question

Making a search result list (like in Google) is not very hard, if you just need something that works. Now, however, I want to do it with perfection, using the benefits of HTML5 semantics. The goal is to define the defacto way of marking up a search result list that potentially could be used by any future search engine.

For each hit, I want to

• order them by increasing number
• display a clickable title
• show a short summary
• display additional data like categories, publishing date and file size

My first idea is something like this:

<ol>
  <li>
    <article>
      <header>
        <h1>
          <a href="url-to-the-page.html">
            The Title of the Page
          </a>
        </h1>
      </header>
      <p>A short summary of the page</p>
      <footer>
        <dl>
          <dt>Categories</dt>
          <dd>
            <nav>
               <ul>
                  <li><a href="first-category.html">First category</a></li>
                  <li><a href="second-category.html">Second category</a></li>
                </ul>
            </nav>
          </dd>
          <dt>File size</dt>
          <dd>2 kB</dd>
          <dt>Published</dt>
          <dd>
            <time datetime="2010-07-15T13:15:05-02:00" pubdate>Today</time>
          </dd>
        </dl>
      </footer>
    </article>
  </li>
  <li>
    ...
  </li>
  ...
</ol>

I am not really happy about the <article/> within the <li/>. First, the search result hit is not an article by itself, but just a very short summary of one. Second, I am not even sure you are allowed to put an article within a list.

Maybe the <details/> and <summary/> tags are more suitable than <article/>, but I don't know if I can add a <footer/> inside that?

All suggestions and opinions are welcome! I really want every single detail to be perfect.

Answer 1

1) I think you should stick with the article element, as

[t]he article element represents a self-contained composition in a document, page, application, or site and that is intended to be independently distributable or reusable [source]

You merely have a list of separate documents, so I think this is fully appropriate. The same is true for the front page of a blog, containing several posts with titles and outlines, each in a separate article element. Besides, if you intend to quote a few sentences of the articles (instead of providing summaries), you could even use blockquote elements, like in the example of a forum post showing the original posts a user is replying to.

2) If you're wondering if it's allowed to include article elements inside a li element, just feed it to the validator. As you can see, it is permitted to do so. Moreover, as the Working Draft says:

Contexts in which this element may be used:

Where flow content is expected.

3) I wouldn't use nav elements for those categories, as those links are not part of the main navigation of the page:

only sections that consist of major navigation blocks are appropriate for the nav element. In particular, it is common for footers to have a short list of links to various pages of a site, such as the terms of service, the home page, and a copyright page. The footer element alone is sufficient for such cases, without a nav element. [source]

4) Do not use the details and/or summary elements, as those are used as part of interactive elements and are not intended for plain documents.

UPDATE: Regarding if it's a good idea to use an (un)ordered list to present search results:

The ul element represents a list of items, where the order of the items is not important — that is, where changing the order would not materially change the meaning of the document. [source]

As a list of search results actually is a list, I think this is the appropriate element to use; however, as it seems to me that the order is important (I expect the best matching result to be on top of the list), I think that you should use an ordered list (ol) instead:

The ol element represents a list of items, where the items have been intentionally ordered, such that changing the order would change the meaning of the document. [source]

Using CSS you can simply hide the numbers.

EDIT: Whoops, I just realized you already use an ol (due to my fatique, I thought you used an ul). I'll leave my ‘update’ as is; after all, it might be useful to someone.