Convert views_ajax_autocomplete_taxonomy() to a Controller

Since this is an AJAX callback rather than a full page callback, we should wait on #1944472: Add generic content handler for returning dialogs.

#1944472: Add generic content handler for returning dialogs is in.

I think instead of converting it to a route, we should probably convert Views to use [#1801356‎], no?

Theoretically #1169964: Taxonomy autocomplete: decouple from Field API and factor out a helper so that code is reusable would have allowed us to not have our own code, but well now that taxonomy uses the entity reference callback we are basically lost.

@tstoeckler that issue doesn't appear to exist, what were you trying to reference?

Don't know why Drupal.org hates me, but the issue does exist: http://drupal.org/node/1801356. It's the issue (that's already in) about a generic entity reference autocomplete. The problem is that views wants an autocomplete that does not rely on a field, but only filters taxonomy terms by bundle. I still think that should be a generic utility somewhere, but @dawehner is right, that Entity Reference doesn't make sense, as that is solely about fields. Maybe we can make a generic EntityAutocomplete in \Drupal\Core\Entity that Entity Reference extends?

Actually, there is a patch for ER that tries to solve exactly this use case, make the generic entity reference available as a form element that doesn't rely on fields. The code is not quite ready yet and I've been awfully slow at reviewing it, but Views is exactly the reason why I pushed my colleague (@goldorak) to submit it as a D8 patch first. Here's the issue: #1959806: Provide a generic 'entity_autocomplete' Form API element

Re #8: Thanks @amateescu, I wasn't aware of that issue. Should we re-title this "Remove views_ajax_autocomplete_taxonomy()" and postpone on that one?

Yep, that sounds like a good plan.

OK. :-)

#1959806: Provide a generic 'entity_autocomplete' Form API element is currently categorized as a feature request and has had no activity in 3 months. Meanwhile, this issue is part of a critical meta, so shouldn't be postponed on that one.

It is good to know that views already has a test for it.

In theory you could argue to just move this code to the autocomplete controller of taxonomy and reuse most of the code.

+++ b/core/modules/views/lib/Drupal/views/Controller/TagsAutocompleteController.php
@@ -0,0 +1,125 @@
+} ¶

Other then this white space RTBC.

There we go. Leaving at RTBC.

CNR for bot.

TaxonomyIndexTid::valueForm() needs to change the #autocomplete_path to #autocomplete_route_name. If #16 passes tests, that also means we're missing test coverage for this autocomplete appearing.

+++ b/core/modules/views/views.module
@@ -322,13 +322,6 @@
-    'theme callback' => 'ajax_base_page_theme',

I was also going to remove the menu item but @dawehner said we can't remove menu items with theme callback.

That's generally correct, but autocomplete controllers aren't ajax in the sense of Drupal's Ajax API, so don't require this theme callback.

Tagging per #17.

Here's the test.

And the fix.

Oh right I agree to remove the 'theme callback'. The request is not a classical ajax request, which pulls down potentially other CSS but it just returns the JSON result.

It is green it has tests and clean conversion so back to RTBC.

#22: vdc-1979038-22.patch queued for re-testing.

Conversion looks fine, but while we're moving this, why not just put it in taxonomy module?

+++ b/core/modules/views/lib/Drupal/views/Controller/TagsAutocompleteController.php
@@ -0,0 +1,125 @@
+use Drupal\Core\Controller\ControllerInterface;

This needs to use the new Drupal\Core\Controller\ContainerInjectionInterface as ControllerInterface no longer exists. See #2057589: [Docs clean-up] Rename ControllerInterface to ContainerInjectionInterface

This adds a new method on the taxonomy autocompletion and reuses as much as possible.

#28: views_taxonomy_ajax-1979038-28.patch queued for re-testing.

Fixed it.

As #26 is addressed. Back to RTBC.

Manually tested works fine

But

1. +++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Controller/TermAutocompleteController.php
   @@ -129,34 +130,82 @@ public function autocomplete(Request $request, $entity_type, $field_name) {
   +   * @return \Symfony\Component\HttpFoundation\JsonResponse|\Symfony\Component\HttpFoundation\Response
   +   *   When valid field name is specified, a JSON response containing the
   +   *   autocomplete suggestions for taxonomy terms. Otherwise a normal response
   +   *   containing an error message.
   +   */
   +  public function autocompletePerVid(Request $request, VocabularyInterface $taxonomy_vocabulary) {
   

   This will never return a normal response.

2. +++ b/core/modules/views/includes/ajax.inc
   @@ -80,53 +80,5 @@ function views_ajax_form_wrapper($form_id, &$form_state) {
   -  $tags_typed = Tags::explode(Drupal::request()->query->get('q'));
   -  $tag_last = Unicode::strtolower(array_pop($tags_typed));
   ...
   -      $term_matches[$prefix . $n] = String::checkPlain($name);
   ...
   -  return new JsonResponse($term_matches);
   

   All the respective use statements for these classes can be removed from the top of this file. They are no longer used.

Good points!

Back to RTBC as #34 is fixed.

Committed and pushed to 8.x. Thanks!