Add sidebar to page template

[haringsrob]

provides a left sidebar as per the markup here: https://ec.europa.eu/component-library/playground/ec/?path=/story/templates-pages--search

[haringsrob]

Tagged with ecl2 because the target is 2.x

[voidtek]

According to https://ec.europa.eu/component-library/ec/templates/pages/search/code/ this div should be an aside and we should change the main by a section.

[ademarco]

I would not add a sidebar in the main theme. Still this is a good occasion to improve our theme to be more extensible by sub-themes (which, I guess, you are using @haringsrob).

In order to do that we could maybe rework this PR using Twig blocks on the page template, so that you could simply override a content block in your page template that extends our.

If you are ok with this approach please consider updating the documentation too.

[ademarco]

See comment above.

[haringsrob]

Can be done by adding a page.html.twig to your subtheme.

{% set _main_content_class = page.sidebar ? 'ecl-col-12 ecl-col-lg-9' : 'ecl-col' %}

{% block content %}
  <section class="main-content ecl-u-mv-l">
    <div class="ecl-container">
      <div class="ecl-row">
        {% if page.sidebar %}
          <div class="ecl-col-12 ecl-col-lg-3">
            {{ page.sidebar }}
          </div>
        {% endif %}
        <div class="{{ _main_content_class }}">
          {{ page.content }}
        </div>
      </div>
    </div>
  </section>
{% endblock %}

And adding the region to the subtheme.info.yml

  sidebar: "Sidebar"

I still feel that on top of this theme a subset of functions can be provided to site builders that allow easier configuration of these sort of pages.