✨ Add migration for flat structure

Classes/ContentRepository/Transformations/FlatStructureTransformation.php

@@ -0,0 +1,59 @@
+<?php
+
+namespace Jonnitto\ImagesInARow\ContentRepository\Transformations;
+
+use Neos\ContentRepository\Domain\Model\NodeInterface;
+use Neos\ContentRepository\Domain\Model\NodeData;
+use Neos\ContentRepository\Migration\Transformations\AbstractTransformation;
+use Neos\Neos\Controller\CreateContentContextTrait;
+
+/**
+ * Move content of collections to the container
+ */
+class FlatStructureTransformation extends AbstractTransformation
+{
+    use CreateContentContextTrait;
+
+    /**
+     * @param NodeData $node
+     * @return boolean
+     */
+    public function isTransformable(NodeData $node)
+    {
+        $numberOfChildNodes = $node->getNumberOfChildNodes('Neos.Neos:ContentCollection', $node->getWorkspace(), $node->getDimensions());
+        return ($numberOfChildNodes > 0);
+    }
+
+    /**
+     * @param NodeData $node
+     * @return void
+     */
+    public function execute(NodeData $node)
+    {
+        $contentContext = $this->createContentContext('live', []);
+        $containerNode = $contentContext->getNodeByIdentifier($node->getIdentifier());
+        $contentCollections = $containerNode->getChildNodes('Neos.Neos:ContentCollection');
+
+        foreach ($contentCollections as $contentCollection) {
+            /** @var NodeInterface $contentCollection */
+            if ($contentCollection->hasChildNodes()) {
+                $this->moveChildNodes($contentCollection->getChildNodes(), $containerNode);
+                $contentCollection->remove();
+            }
+        }
+    }
+
+    /**
+     * @param array $children
+     * @param NodeInterface $container
+     */
+    protected function moveChildNodes(array $children, NodeInterface $container)
+    {
+        foreach ($children as $childNode) {
+            if ($childNode instanceof NodeInterface) {
+                /** @var NodeInterface $childNode */
+                $childNode->moveInto($container);
+            }
+        }
+    }
+}

Migrations/ContentRepository/Version20200823164840.yaml

@@ -0,0 +1,12 @@
+up:
+  comments: 'Migrate content collection of images to a flat structure'
+  migration:
+    - filters:
+        - type: 'NodeType'
+          settings:
+            nodeType: 'Jonnitto.ImagesInARow:Container'
+      transformations:
+        - type: 'Jonnitto\ImagesInARow\ContentRepository\Transformations\FlatStructureTransformation'
+          settings: []
+down:
+  comments: 'No down migration available'