How to make exposed filters more readable in the URL?

Question

I'm trying to make my URLs a bit more readable (and persistent) which includes query parameters of a view's page. Usually the URL would look like this when I define an exposed filter which is addressed by the parameter vocabulary-foo: https://www.example.com/view?vocabulary-foo[]=1234. As you might have noticed, this is a filter for taxonomy terms of a specific vocabulary. There are two problems with the usage of IDs in the URL, which I'd like to solve:

• If I uninstall my custom module that creates the taxonomy terms, these are gone and will get another ID when I install the module again. So I can't assume a link to a specific filtered view page would then still be the same.

• It's not readable (and memorizable). Using the term's value instead of the ID would probably already help me. On the other hand, if it is possible to define a query parameter preset=something which translates to vocabulary-foo[]=<The id of the term which has a specific value>, I'd rather do that as it enables me to combine multiple query parameters to one preset, which makes it shorter.

In my specific case, the view exposes a form which can be used to search for content. A preset as described would pre-select some form controls with only one clean URL parameter.

One idea that came to my mind was somehow using PHP's $_GET variable and conditionally changing its content before the view is created. Unfortunately, I don't know which hook would be suitable for that.

Has somebody faced a similar issue in the past? How could I solve these problems in Drupal 9? Thanks!

Answer 1

There's no easy way to do that .. views better_exposed_filters is quite nice, but does not provide clean urls. Drupal 7 had query_parameters_to_url, for Drupal 8 they link to a sandbox! project ... This may be a starting point for you.

There may be a simpler approach here: Redirect based on query string using a redirect event subscriber:

<?php
    static function getSubscribedEvents()
    {
        $events[KernelEvents::REQUEST][] = array('Redirect', 20);
        return $events;
    }

So you could provide at least clean urls to "somewhere".

Answer 2

Assuming you have a term name called "Hello World"

So you want https://www.example.com/view?vocabulary-foo=hello-world to work.

/**
 * Implements hook_views_pre_view.
 */
function mymodule_views_pre_view(\Drupal\views\ViewExecutable $view, $display_id, array &$args) {
  $term_name = \Drupal::request()->query->get('vocabulary-foo'); // equals hello-world
  if (!empty($term_name)) {
    $args = [];
    $term_name = str_replace('-', ' ', $term_name); // equals hello world
    // get term id from name
    $term = \Drupal::entityTypeManager()->getStorage('taxonomy_term')
      ->loadByProperties(['name' => $term_name, 'vid' => 'vocabulary_foo']);
    $term = reset($term);
    $term_id = $term->id();
    // set argument
    $args[] = $term_id;
  }
}