TASK: Introduce trait ActionToMethodDelegation instead of `SimpleAc…

…tionController`.

The name of the previously suggested `SimpleActionController` looked for improvement.

The `Simple*` prefix suggest, that the initial implementation blew up too much. But ideally a name would be more obvious and not suggest that there is another _complex_ action controller.

 I could not come up with a better name, but we can make the controllers more composable.

 This change introduces a trait which implements the logic of the previous `SimpleActionController`.
 That way people can implement the `ControllerInterface` directly and use a trait that will map action to method name.

Neos.Flow/Classes/Mvc/Controller/ActionToMethodDelegation.php

@@ -0,0 +1,59 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Neos\Flow\Mvc\Controller;
+
+use Neos\Flow\Mvc\ActionRequest;
+use Neos\Flow\Mvc\ActionResponse;
+use Neos\Flow\Mvc\Exception\NoSuchActionException;
+
+/**
+ * Helps to implement a controller with direct access to flows request/response abstraction.
+ *
+ * ```
+ * ┌─────────────────────────────────────────────────────────────────────────────┐
+ * │ class MyController implements ControllerInterface                           │
+ * │ {                                                                           │
+ * │     use ActionToMethodDelegation;                                           │
+ * │     public function myAction(ActionRequest $actionRequest): ActionResponse; │
+ * │ }                                                                           │
+ * └─────────────────────────────────────────────────────────────────────────────┘
+ * ```
+ *
+ * The request comes directly from the dispatcher and goes directly back to it.
+ *
+ * For helpers to facilitate throws, forwards, redirects: {@see SpecialResponsesSupport}
+ *
+ * Views or other processing needs to be added to your controller as needed,
+ * helpers will be suggested here as they become available.
+ * @api
+ */
+trait ActionToMethodDelegation
+{
+    /**
+     * @internal you don't need to use this trait if you need to override this functionality.
+     */
+    final public function processRequest(ActionRequest $request): ActionResponse
+    {
+        $request->setDispatched(true);
+        $actionMethodName = $this->resolveActionMethodName($request);
+        return $this->$actionMethodName($request);
+    }
+
+    /**
+     * Resolves and checks the current action method name
+     *
+     * @return string Method name of the current action
+     * @throws NoSuchActionException
+     */
+    private function resolveActionMethodName(ActionRequest $request): string
+    {
+        $actionMethodName = $request->getControllerActionName() . 'Action';
+        if (!is_callable([$this, $actionMethodName])) {
+            throw new NoSuchActionException(sprintf('An action "%s" does not exist in controller "%s".', $actionMethodName, get_class($this)), 1186669086);
+        }
+
+        return $actionMethodName;
+    }
+}

Neos.Flow/Tests/Functional/Mvc/Fixtures/Controller/SimpleActionControllerTestController.php

@@ -3,13 +3,13 @@
 
 use Neos\Flow\Mvc\ActionRequest;
 use Neos\Flow\Mvc\ActionResponse;
-use Neos\Flow\Mvc\Controller\SimpleActionController;
+use Neos\Flow\Mvc\Controller\ActionToMethodDelegation;
+use Neos\Flow\Mvc\Controller\ControllerInterface;
 
-/**
- *
- */
-class SimpleActionControllerTestController extends SimpleActionController
+class SimpleActionControllerTestController implements ControllerInterface
 {
+    use ActionToMethodDelegation;
+
     public function indexAction(ActionRequest $actionRequest): ActionResponse
     {
         $response = new ActionResponse();

Neos.Flow/Tests/Unit/Mvc/Controller/SimpleActionControllerTest.php → Neos.Flow/Tests/Unit/Mvc/Controller/ActionToMethodDelegationTest.php

@@ -13,15 +13,14 @@
 
 use Neos\Flow\Mvc\ActionRequest;
 use Neos\Flow\Mvc\ActionResponse;
-use Neos\Flow\Mvc\Controller\SimpleActionController;
+use Neos\Flow\Mvc\Controller\ActionToMethodDelegation;
 use Neos\Flow\Mvc\Exception\NoSuchActionException;
 use Neos\Flow\Tests\UnitTestCase;
 
 /**
- * Tests for
- * @see SimpleActionController
+ * Tests for @see ActionToMethodDelegation
  */
-class SimpleActionControllerTest extends UnitTestCase
+class ActionToMethodDelegationTest extends UnitTestCase
 {
     /**
      * Note: additional checks like "123" or "Foo" might seem sensible but those cases are prevented in the ActionRequest already.

Neos.Flow/Tests/Unit/Mvc/Controller/Fixtures/SimpleActionTestController.php

@@ -3,13 +3,13 @@
 
 use Neos\Flow\Mvc\ActionRequest;
 use Neos\Flow\Mvc\ActionResponse;
-use Neos\Flow\Mvc\Controller\SimpleActionController;
+use Neos\Flow\Mvc\Controller\ActionToMethodDelegation;
+use Neos\Flow\Mvc\Controller\ControllerInterface;
 
-/**
- *
- */
-class SimpleActionTestController extends SimpleActionController
+class SimpleActionTestController implements ControllerInterface
 {
+    use ActionToMethodDelegation;
+
     public function addTestContentAction(ActionRequest $actionRequest): ActionResponse
     {
         $response = new ActionResponse();