From f101fe830e87c627be3ebaf42c863991ed81fa41 Mon Sep 17 00:00:00 2001
From: Sander de Vos <sander@tutanota.de>
Date: Sun, 29 Jul 2018 16:26:51 +0200
Subject: [PATCH] Resolves #16

---
 readme.md                  |  5 ++--
 src/Contracts/Portable.php | 20 ++++++++++++++
 src/Portable.php           | 54 +++++++++++++++++++++++++++++++++++++-
 3 files changed, 76 insertions(+), 3 deletions(-)
 create mode 100644 src/Contracts/Portable.php

diff --git a/readme.md b/readme.md
index 70dfa40..ec82444 100644
--- a/readme.md
+++ b/readme.md
@@ -26,7 +26,7 @@ After installing the package, you should publish the configuration file:
 $ php artisan vendor:publish --tag=gdpr-config
 ```
 
-Finally, add the `Soved\Laravel\Gdpr\Portable` trait to the `App\User` model:
+Finally, add the `Soved\Laravel\Gdpr\Portable` trait to the `App\User` model and implement the `Soved\Laravel\Gdpr\Contracts\Portable` contract:
 
 ```php
 <?php
@@ -36,8 +36,9 @@ namespace App;
 use Soved\Laravel\Gdpr\Portable;
 use Illuminate\Notifications\Notifiable;
 use Illuminate\Foundation\Auth\User as Authenticatable;
+use Soved\Laravel\Gdpr\Contracts\Portable as PortableContract;
 
-class User extends Authenticatable
+class User extends Authenticatable implements PortableContract
 {
     use Portable, Notifiable;
 }
diff --git a/src/Contracts/Portable.php b/src/Contracts/Portable.php
new file mode 100644
index 0000000..6050f6a
--- /dev/null
+++ b/src/Contracts/Portable.php
@@ -0,0 +1,20 @@
+<?php
+
+namespace Soved\Laravel\Gdpr\Contracts;
+
+interface Portable
+{
+    /**
+     * Convert the model instance to a GDPR compliant data portability array.
+     *
+     * @return array
+     */
+    public function portable();
+
+    /**
+     * Get the GDPR compliant data portability array for the model.
+     *
+     * @return array
+     */
+    public function toPortableArray();
+}
diff --git a/src/Portable.php b/src/Portable.php
index 2a8ab18..edcd80c 100644
--- a/src/Portable.php
+++ b/src/Portable.php
@@ -2,6 +2,8 @@
 
 namespace Soved\Laravel\Gdpr;
 
+use Soved\Laravel\Gdpr\Contracts\Portable as PortableContract;
+
 trait Portable
 {
     /**
@@ -13,7 +15,7 @@ public function portable()
     {
         // Eager load the given relations
         if (isset($this->gdprWith)) {
-            $this->loadMissing($this->gdprWith);
+            $this->loadRelations($this->gdprWith);
         }
 
         // Make the given attributes visible
@@ -29,6 +31,56 @@ public function portable()
         return $this->toPortableArray();
     }
 
+    /**
+     * Eager load the given relations.
+     *
+     * @param  array  $relations
+     * @return void
+     */
+    public function loadRelations(array $relations)
+    {
+        $portableRelations = $this->getPortableRelations($relations);
+
+        array_walk($portableRelations, [$this, 'loadPortableRelation']);
+
+        $this->load(array_diff($relations, $portableRelations));
+    }
+
+    /**
+     * Get all portable relations.
+     *
+     * @param  array  $relations
+     * @return array
+     */
+    private function getPortableRelations(array $relations)
+    {
+        $portableRelations = [];
+
+        foreach ($relations as $relation) {
+            if ($this->$relation()->getRelated() instanceof PortableContract) {
+                $portableRelations[] = $relation;
+            }
+        }
+
+        return $portableRelations;
+    }
+
+    /**
+     * Load and transform a portable relation.
+     *
+     * @param  string  $relation
+     * @return void
+     */
+    private function loadPortableRelation(string $relation)
+    {
+        $this->attributes[$relation] = $this
+            ->$relation()
+            ->get()
+            ->transform(function ($item) {
+                return $item->portable();
+            });
+    }
+
     /**
      * Get the GDPR compliant data portability array for the model.
      *