Error with custom enhancer defined with attributes

Root cause
In ResourceFieldEnhancerManager::alterDefinitions(), the code iterates over $definition_info['dependencies'] and passes each value directly to $this->moduleHandler->moduleExists(). However, plugin definitions using the #[ResourceFieldEnhancer] attribute declare dependencies as a flat array (e.g., dependencies: ['datetime']), but during plugin discovery the dependencies value can be structured as a keyed array (e.g., ['module' => ['datetime']]). When the value is a nested array, it gets passed as-is to moduleExists(), which calls isset($this->moduleList[$module]) — triggering a TypeError in PHP 8.1+ because an array cannot be used as an array offset in isset().

Fix
Flatten the dependencies array before iterating, so both flat (['datetime']) and nested (['module' => ['datetime']]) formats are handled correctly.

PS: The existing partial fix (the is_string check) was incorrect — it silently skipped array dependencies without validating them, so plugins with unmet nested dependencies would still be loaded.

I have tested https://www.drupal.org/files/issues/2026-04-22/jsonapi_extras-3584099-3.... against one of my projects. The routes no longer give a 500 error, but instead give the desired output.

I think i need to check if this change will break ealier versions.

Ran into this issue this morning - loaded up the patch from #3 and the page loads as intended.

Thanks!

I tried Patch #3 and the error still appears. I verified the patch definitely applied and the changes appeared. I'm running jsonapi_extras 8.x-3.28.

I'm trying to access the 'Override' page for several entities, but found the error also fires when attempting to edit existing overrides. I'm also not defining any enhancers or plugins.

The full error is:

TypeError: Cannot access offset of type array in isset or empty in Drupal\Core\Extension\ModuleHandler->moduleExists() (line 267 of core/lib/Drupal/Core/Extension/ModuleHandler.php).
Drupal\jsonapi_extras\Plugin\ResourceFieldEnhancerManager->alterDefinitions() (Line: 344)
Drupal\Core\Plugin\DefaultPluginManager->findDefinitions() (Line: 216)
Drupal\Core\Plugin\DefaultPluginManager->getDefinitions() (Line: 412)
Drupal\jsonapi_extras\Form\JsonapiResourceConfigForm->buildOverridesField() (Line: 309)
Drupal\jsonapi_extras\Form\JsonapiResourceConfigForm->buildOverridesForm() (Line: 138)
Drupal\jsonapi_extras\Form\JsonapiResourceConfigForm->form() (Line: 108)
Drupal\Core\Entity\EntityForm->buildForm()
call_user_func_array() (Line: 559)
Drupal\Core\Form\FormBuilder->retrieveForm() (Line: 299)
Drupal\Core\Form\FormBuilder->buildForm() (Line: 73)
Drupal\Core\Controller\FormController->getContentResult()
call_user_func_array() (Line: 123)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->{closure:Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber::wrapControllerExecutionInRenderContext():121}() (Line: 638)
Drupal\Core\Render\Renderer::{closure:Drupal\Core\Render\Renderer::executeInRenderContext():638}()
Fiber->resume() (Line: 653)
Drupal\Core\Render\Renderer->executeInRenderContext() (Line: 121)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext() (Line: 97)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->{closure:Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber::onController():96}() (Line: 183)
Symfony\Component\HttpKernel\HttpKernel->handleRaw() (Line: 76)
Symfony\Component\HttpKernel\HttpKernel->handle() (Line: 53)
Drupal\Core\StackMiddleware\Session->handle() (Line: 30)
Drupal\Core\StackMiddleware\KernelPreHandle->handle() (Line: 28)
Drupal\Core\StackMiddleware\ContentLength->handle() (Line: 118)
Drupal\page_cache\StackMiddleware\PageCache->pass() (Line: 92)
Drupal\page_cache\StackMiddleware\PageCache->handle() (Line: 263)
Drupal\shield\ShieldMiddleware->bypass() (Line: 154)
Drupal\shield\ShieldMiddleware->handle() (Line: 53)
Asm89\Stack\Cors->handle() (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle() (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle() (Line: 61)
Drupal\Core\StackMiddleware\AjaxPageState->handle() (Line: 54)
Drupal\Core\StackMiddleware\StackedHttpKernel->handle() (Line: 753)
Drupal\Core\DrupalKernel->handle() (Line: 34)
Symfony\Component\Runtime\Runner\Symfony\HttpKernelRunner->run() (Line: 32)
require('/var/www/html/vendor/autoload_runtime.php') (Line: 22)
require_once('/var/www/html/web/autoload_runtime.php') (Line: 13)

Did some testing and this fix will drop dependencies, which is not nice. The fix will be to actually move things around. I will keep a BC path for the enhancers but will emit a deprecation.

Fixed, thanks all