fix some problems

app/Http/Resources/TransferResource.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace App\Http\Resources;
+
+use Illuminate\Http\Request;
+use Illuminate\Http\Resources\Json\JsonResource;
+
+class TransferResource extends JsonResource
+{
+    /**
+     * Transform the resource into an array.
+     *
+     * @param  Request  $request
+     * @return array
+     */
+    public function toArray($request)
+    {
+        return [
+            'id' => $this->id,
+            'from_date' => $this->from_date,
+            'to_date' => $this->to_date,
+            'status' => $this->status,
+            'user_id' => $this->user_id,
+            'user' => UserResource::make($this->whenLoaded('user')),
+            'transferable' => $this->resourceFinder(),
+            'created_at' => $this->created_at,
+            'updated_at' => $this->updated_at
+        ];
+    }
+
+    private function resourceFinder()
+    {
+        if ($this->whenLoaded('transferable')) {
+            if ($this->transferable_type == "App\\Package"){
+                return PackageResource::make($this->transferable);
+            }elseif($this->transferable_type == "App\\Item"){
+                return ItemResource::make($this->transferable);
+            }
+        }
+    }
+}