Deprecate feed.bridge.writer

I once had the honour to use zend writer in a project. I don't remember the exact details, nor do I have the source code, but it turned out the bridge in Drupal was broken, can't say how anymore though :(

Regarding usage in contrib:

$ ag "feed.bridge"
feeds/src/Feeds/Parser/SyndicationParser.php
32:    Reader::setExtensionManager(\Drupal::service('feed.bridge.reader'));

feeds/src/Utility/Feed.php
47:    Reader::setExtensionManager(\Drupal::service('feed.bridge.reader'));

feeds/tests/src/Unit/Feeds/Parser/SyndicationParserTest.php
48:    $container->set('feed.bridge.reader', $manager);

feeds_brighttalk/copy-to-feeds/BrightTALKParser.php
32:    Reader::setExtensionManager(\Drupal::service('feed.bridge.reader'));

feeds_brighttalk/src/Feeds/Parser/BrightTALKParser.php
32:    Reader::setExtensionManager(\Drupal::service('feed.bridge.reader'));

ide_helper/src-dev/expected/Unish/PhpStormMeta/drupal.core.php
185:      'feed.bridge.reader' => \Zend\Feed\Reader\ExtensionManagerInterface::class,
186:      'feed.bridge.writer' => \Zend\Feed\Reader\ExtensionManagerInterface::class,
574:      'feed.bridge.reader' => \Zend\Feed\Reader\ExtensionManagerInterface::class,
575:      'feed.bridge.writer' => \Zend\Feed\Reader\ExtensionManagerInterface::class,

Something we could certainly talk about is to mark it as deprecated. On the longrun we could tell people to use internal services + composer dependencies if they really want to.

I agree with #5, marking it as deprecated sounds like a good idea. I don't think we can just remove it.

+++ b/core/tests/Drupal/KernelTests/Core/LegacyServiceTest.php
@@ -41,6 +41,14 @@ public function testLaminasFeedServices($type, $service, $class) {
+    $this->expectDeprecation("The \"feed.bridge.writer\" service is deprecated in drupal:9.4.0 and is removed from drupal:10.0.0. Use \Laminas\Feed\Writer\StandaloneExtensionManager or create your own service. See https://www.drupal.org/node/3258440");

We better update the deprecation that we just added that points to this service :)

    deprecated: The "%service_id%" service is deprecated in drupal:9.4.0 and is removed from drupal:10.0.0. You should use \Drupal::service('feed.bridge.writer')->get('Atom\Renderer\Feed') instead. See https://www.drupal.org/node/2979042

Now we have deprecated all the feed.(reader|writer).* services what is the point of feed.bridge.reader and ZfExtensionManagerSfContainer?

Would we be better off wrapping Laminas\Feed\Reader\StandaloneExtensionManager in a service, perhaps with a service collector that allows users to add new feed types?

I think it'd be worth going ahead with what we have here, then opening follow-ups for #20-22 - just to make sure we get this deprecation in now, and not in another four years.

In general, once #3188549: [Meta] Tasks to deprecate both Aggregator and our dependency on Laminas Feed is done, we can remove Laminas/Feed entirely from core. #2003108: Switch Views RSS to use Serializer/Zend never happened so it is only used by aggregator. We need to deprecate all of the services in order to remove them, but not really worth expending effort trying to clean up an integration we're going to nuke entirely.

OK, let's just get this small part done and defer the rest to followups if needed. Not even sure #21 is relevant if nobody is using this in contrib and earlier reports suggest the writer service doesn't work anyway.

Sure but let's do that in a followup, deprecating the writer is easy because nobody uses it, restructuring the reader means moving ZfExtensionManagerSfContainer and deprecating the entire Bridge component I think, which seems much more complicated.

Committed/pushed to 10.0.x and cherry-picked to 9.4.x, thanks!

Published the change record.