[FEATURE] New DataProcessor: ExtractPropertyProcessor

Classes/DataProcessing/ExtractPropertyProcessor.php

@@ -0,0 +1,75 @@
+<?php
+
+/*
+ * This file is part of the "headless" Extension for TYPO3 CMS.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.md file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace FriendsOfTYPO3\Headless\DataProcessing;
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Frontend\ContentObject\ContentObjectRenderer;
+use TYPO3\CMS\Frontend\ContentObject\DataProcessorInterface;
+
+/**
+ * Extract a single (maybe nested) property from a given array
+ *
+ * Example:
+ * lib.meta.fields.ogImage = TEXT
+ * lib.meta.fields.ogImage {
+ *     dataProcessing {
+ *         10 = FriendsOfTYPO3\Headless\DataProcessing\FilesProcessor
+ *         ...
+ *
+ *         20 = FriendsOfTYPO3\Headless\DataProcessing\ExtractPropertyProcessor
+ *         20.key = media.publicUrl
+ *         20.as = media
+ *     }
+ * }
+ */
+class ExtractPropertyProcessor implements DataProcessorInterface
+{
+    /**
+     * Extract a single (maybe nested) property from a given array
+     *
+     * @param ContentObjectRenderer $cObj The content object renderer, which contains data of the content element
+     * @param array $contentObjectConfiguration The configuration of Content Object
+     * @param array $processorConfiguration The configuration of this processor
+     * @param array $processedData Key/value store of processed data (e.g. to be passed to a Fluid View)
+     * @return array the processed data as key/value store
+     */
+    public function process(
+        ContentObjectRenderer $cObj,
+        array $contentObjectConfiguration,
+        array $processorConfiguration,
+        array $processedData
+    ) {
+        if (empty($processorConfiguration['as'])) {
+            throw new \Exception('Please specify property \'as\'');
+        }
+
+        if (empty($processorConfiguration['key'])) {
+            throw new \Exception('Please specify property \'key\'');
+        }
+
+        $targetFieldName = (string)$cObj->stdWrapValue(
+            'as',
+            $processorConfiguration
+        );
+
+        $key = GeneralUtility::trimExplode('.', $processorConfiguration['key'], true);
+
+        // Extract (nested) property
+        do {
+            $processedData = $processedData[array_shift($key)] ?? null;
+        } while (count($key));
+
+        return [
+            $targetFieldName => $processedData
+        ];
+    }
+}

Documentation/Developer/Index.rst

@@ -297,6 +297,34 @@ Here's an example of how to override the meta object by data from a DB record:
     }
   }
 
+.. _developer-dataprocessors:
+
+TypoScript DataProcessors
+=========================
+
+This extension provides a couple of handy DataProcessors. Have a look into the default TypoScript to see them in action.
+
+Here's an example demonstrating their usage.
+
+.. code-block:: typoscript
+
+  lib.meta.fields.ogImage = TEXT
+  lib.meta.fields.ogImage {
+    dataProcessing {
+      # Use the column 'og_image' to render an array with all relevant
+      # information (such as the publicUrl)
+      10 = FriendsOfTYPO3\Headless\DataProcessing\FilesProcessor
+      10.as = media
+      10.references.fieldName = og_image
+      10.processingConfiguration.returnFlattenObject = 1
+
+      # Extract only property 'publicUrl' from the above created array
+      20 = FriendsOfTYPO3\Headless\DataProcessing\ExtractPropertyProcessor
+      20.key = media.publicUrl
+      20.as = media
+    }
+  }
+
 .. _developer-ext-form:
 
 EXT:form & form output decorators