add Serializer class & edit retrieve method in CustomField class

Author: PapiHack

src/CustomField.php

@@ -3,6 +3,7 @@
 namespace PayTech;
 
 use Exception;
+use PayTech\Utils\Serializer;
 
 /**
  * 
@@ -38,6 +39,6 @@ public static function find($name)
 
     public static function retrieve()
     {
-        return self::$data;
+        return new Serializer(self::$data);
     }
 }

src/Utils/Serializer.php

@@ -0,0 +1,60 @@
+<?php
+
+namespace PayTech\Utils;
+
+/**
+ * 
+ * @author PapiHack
+ * @since 07/2020
+ * 
+ */
+Class Serializer 
+{
+    private  $data = [];
+
+    public function __construct(Array $data)
+    {
+        $this->setData($data);
+    }
+
+    public function getData() 
+    {
+        return $this->data;
+    }
+
+    public function setData(Array $data) 
+    {
+        $this->data = $data;
+    }
+
+    public function toJSONString()
+    {
+        return json_encode($this->data);
+    }
+
+    public function toXMLString()
+    {
+        return $this->arrayToXml($this->data, '<custom_fields/>');
+    }
+
+    public function toQueryString()
+    {
+        return http_build_query($this->data);
+    }
+
+    private function arrayToXml($array, $rootElement = null, $xml = null) { 
+        $xmlDocument = $xml; 
+
+        if ($xmlDocument === null) 
+        { 
+            $xmlDocument = new \SimpleXMLElement($rootElement !== null ? $rootElement : '<root/>'); 
+        }
+
+        foreach ($array as $key => $value) 
+        {
+            is_array($value) ? $this->arrayToXml($value, $key, $xmlDocument->addChild($key)) : $xmlDocument->addChild($key, $value);
+        } 
+          
+        return $xmlDocument->asXML(); 
+    } 
+}