feat: ContactsToArray transformer

Created by: melanger

allows exporting contacts from Perun into SP metadata

lib/transformers/ContactsToArray.php

+<?php
+
+declare(strict_types=1);
+
+namespace SimpleSAML\Module\perun\transformers;
+
+use SimpleSAML\Configuration;
+use SimpleSAML\Module\perun\AttributeTransformer;
+
+/**
+ * Get contacts array from lists in contact attributes.
+ */
+class ContactsToArray extends AttributeTransformer
+{
+    private $contactTypes;
+
+    private $removeSource;
+
+    private $outputAttr;
+
+    /**
+     * @override
+     */
+    public function __construct(Configuration $config)
+    {
+        $this->contactTypes = $config->getArray('contactTypes');
+        $this->removeSource = !$config->getBoolean('keepSource', true);
+        $this->outputAttr = $config->getString('outputAttr', 'contacts');
+    }
+
+    /**
+     * @override
+     */
+    public function transform(array $attributes)
+    {
+        $result = [];
+        $contacts = [];
+        foreach ($attributes as $attribute => $emailList) {
+            if ($this->removeSource) {
+                $result[$attribute] = null;
+            }
+            if (!empty($emailList) && isset($this->contactTypes[$attribute])) {
+                foreach ($emailList as $email) {
+                    $contacts[] = [
+                        'contactType' => $this->contactTypes[$attribute],
+                        'emailAddress' => $email,
+                    ];
+                }
+            }
+        }
+        // contacts array
+        return array_merge($result, [
+            $this->outputAttr => $contacts,
+        ]);
+    }
+}