at the end of the day, it was inevitable

src/AppBundle/HttpFoundation/AppMergeableResponse.php

@@ -0,0 +1,51 @@
+<?php
+
+namespace AppBundle\HttpFoundation;
+
+/**
+ * Class AppMergeableResponse
+ * Response from app api which merge new data instead or resetting.
+ *
+ * @package AuthenticationBundle\HttpFoundation
+ */
+class AppMergeableResponse extends AppResponse
+{
+
+    /**
+     * @var boolean
+     */
+    protected $isOriginalPriority = false;
+
+    /**
+     * @param boolean $flag Flag, if set original data which set in constructor
+     *                      or by first call of setData method have higher
+     *                      priority than new data.
+     *
+     * @return AppMergeableResponse
+     */
+    public function setOriginalPriority($flag)
+    {
+        $this->isOriginalPriority = $flag;
+
+        return $this;
+    }
+
+    /**
+     * Sets the data to be sent as JSON.
+     *
+     * @param mixed $data New data.
+     *
+     * @return AppMergeableResponse
+     */
+    public function setData($data = [])
+    {
+        if ($this->isOriginalPriority) {
+            $data = $this->data + (array) $data;
+        } else {
+            $data = (array) $data + $this->data;
+        }
+        parent::setData($data);
+
+        return $this;
+    }
+}

src/AppBundle/HttpFoundation/AppResponse.php

@@ -0,0 +1,114 @@
+<?php
+
+namespace AppBundle\HttpFoundation;
+
+use Symfony\Component\HttpFoundation\JsonResponse;
+
+/**
+ * Class SearchResponse
+ * Response from application api.
+ *
+ * @package AuthenticationBundle\HttpFoundation
+ */
+class AppResponse extends JsonResponse
+{
+
+    /**
+     * SearchResponse constructor.
+     *
+     * @param mixed   $data    The response data.
+     * @param integer $status  The response status code.
+     * @param array   $headers An array of response headers.
+     */
+    public function __construct($data = null, $status = 200, array $headers = [])
+    {
+        // Initialize current response data first.
+        $this->data = [];
+
+        if ($data === null) {
+            $data = [];
+        } elseif (is_scalar($data)) {
+            $data = [ $data ];
+        }
+        $headers['Content-Type'] = 'application/json';
+
+        parent::__construct($data, $status, $headers);
+        $this->update();
+    }
+
+    /**
+     * Sets the data to be sent as JSON.
+     *
+     * @param mixed $data Response data.
+     *
+     * @return AppResponse
+     */
+    public function setData($data = [])
+    {
+        // Do not serialize data into json here, but do it in update method.
+        if ($data === null) {
+            $data = [];
+        } elseif (is_scalar($data)) {
+            $data = [ $data ];
+        }
+        $this->data = $data;
+        $this->update();
+
+        return $this;
+    }
+
+    /**
+     * Updates the content and headers according to the JSON data and callback.
+     *
+     * @return AppResponse
+     */
+    protected function update()
+    {
+        $data = $this->data;
+
+        if (($this->statusCode >= 400) && ($this->statusCode !== 402)) {
+            $data = [
+                'errors' => $data,
+            ];
+        }
+
+        return $this->setContent(json_encode($data));
+    }
+
+    /**
+     * Create response with 400 HTTP code.
+     *
+     * @param mixed $data The response data.
+     *
+     * @return static
+     */
+    public static function badRequest($data = 'Bad Request')
+    {
+        return static::create($data, self::HTTP_BAD_REQUEST);
+    }
+
+    /**
+     * Create response with 401 HTTP code.
+     *
+     * @param string $data The response data.
+     *
+     * @return static
+     */
+    public static function unauthorized($data = 'Unauthorized')
+    {
+        return static::create($data, self::HTTP_UNAUTHORIZED);
+    }
+
+    /**
+     * Sends HTTP headers and content.
+     *
+     * @return AppResponse
+     */
+    public function send()
+    {
+        $this->update();
+        parent::send();
+
+        return $this;
+    }
+}