Handle response from Checkout API redirect

Controller/Process/Result.php

@@ -87,7 +87,6 @@ class Result extends \Magento\Framework\App\Action\Action
         $this->_orderHistoryFactory = $orderHistoryFactory;
         $this->_session = $session;
         $this->_adyenLogger = $adyenLogger;
-		$this->storeManager = $storeManager;
         parent::__construct($context);
     }
 
@@ -302,37 +301,33 @@ class Result extends \Magento\Framework\App\Action\Action
     protected function _authenticate($response)
     {
 
-    	if (!empty($response['merchantSig'])) {
-			$merchantSigNotification = $response['merchantSig'];
+		$merchantSigNotification = $response['merchantSig'];
 
-        // do it like this because $_GET is converting dot to underscore
-        $queryString = $_SERVER['QUERY_STRING'];
-        $result = [];
-        $pairs = explode("&", $queryString);
+			// do it like this because $_GET is converting dot to underscore
+			$queryString = $_SERVER['QUERY_STRING'];
+			$result = [];
+			$pairs = explode("&", $queryString);
 
-			foreach ($pairs as $pair) {
-				$nv = explode("=", $pair);
-				$name = urldecode($nv[0]);
-				$value = urldecode($nv[1]);
-				$result[$name] = $value;
-			}
+		foreach ($pairs as $pair) {
+			$nv = explode("=", $pair);
+			$name = urldecode($nv[0]);
+			$value = urldecode($nv[1]);
+			$result[$name] = $value;
+		}
 
-        // do not include the merchantSig in the merchantSig calculation
-        unset($result['merchantSig']);
+			// do not include the merchantSig in the merchantSig calculation
+			unset($result['merchantSig']);
 
-        // Sign request using secret key
-        $hmacKey = $this->_adyenHelper->getHmac();
-        $merchantSig = \Adyen\Util\Util::calculateSha256Signature($hmacKey, $result);
-
-			if (strcmp($merchantSig, $merchantSigNotification) === 0) {
-				return true;
-			}
-			return false;
-		} else{
-    		// send the payload verification payment\details request to validate the response
+			// Sign request using secret key
+			$hmacKey = $this->_adyenHelper->getHmac();
+			$merchantSig = \Adyen\Util\Util::calculateSha256Signature($hmacKey, $result);
 
+		if (strcmp($merchantSig, $merchantSigNotification) === 0) {
+			return true;
 		}
 
+		return false;
+
     }
 
     /**