MAGETWO-53431: [GITHUB] SOAP API Encoding Object has no 'label' property #4630

Author: Alex Paliarush

app/code/Magento/Webapi/Controller/Soap/Request/Handler.php

@@ -5,6 +5,8 @@
  */
 namespace Magento\Webapi\Controller\Soap\Request;
 
+use Magento\Framework\Api\ExtensibleDataInterface;
+use Magento\Framework\Api\MetadataObjectInterface;
 use Magento\Framework\Api\SimpleDataObjectConverter;
 use Magento\Framework\Webapi\Authorization;
 use Magento\Framework\Exception\AuthorizationException;
@@ -155,7 +157,11 @@ protected function _prepareResponseData($data, $serviceClassName, $serviceMethod
         } elseif (is_array($data)) {
             $dataType = substr($dataType, 0, -2);
             foreach ($data as $key => $value) {
-                if ($value instanceof $dataType) {
+                if ($value instanceof $dataType
+                    // the following two options are supported for backward compatibility
+                    || $value instanceof ExtensibleDataInterface
+                    || $value instanceof MetadataObjectInterface
+                ) {
                     $result[] = $this->_dataObjectConverter
                         ->convertKeysToCamelCase($this->_dataObjectProcessor->buildOutputDataArray($value, $dataType));
                 } else {

app/code/Magento/Webapi/Test/Unit/Controller/Soap/Request/HandlerTest.php

@@ -104,6 +104,7 @@ public function testCall()
         $this->_dataObjectConverter->expects($this->once())
             ->method('convertStdObjectToArray')
             ->will($this->returnValue(['field' => 1]));
+        $this->_methodsMapProcessorMock->method('getMethodReturnType')->willReturn('string');
         $operationName = 'soapOperation';
         $className = \Magento\Framework\DataObject::class;
         $methodName = 'testMethod';