Make the property param optional

DependencyInjection/Configuration.php

@@ -511,7 +511,7 @@ class Configuration implements ConfigurationInterface
 
         return $node;
     }
-    
+
     /**
      * Returns the array node used for "_parent".
      */
@@ -523,7 +523,7 @@ class Configuration implements ConfigurationInterface
         $node
             ->children()
                 ->scalarNode('type')->end()
-                ->scalarNode('property')->end()
+                ->scalarNode('property')->defaultValue(null)->end()
                 ->scalarNode('identifier')->defaultValue('id')->end()
             ->end()
         ;

README.md

@@ -182,6 +182,12 @@ per type.
                             content: ~
                         _parent: { type: "post", property: "post", identifier: "id" }
 
+The parent filed declaration has the following values:
+
+ * `type`: The parent type.
+ * `property`: The property in the child entity where to look for the parent entity. It may be ignored if is equal to the parent type.
+ * `identifier`: The property in the parent entity which have the parent identifier. Defaults to `id`.
+
 ### Declaring `nested` or `object`
 
     fos_elastica:

Tests/Transformer/ModelToElasticaAutoTransformerTest.php

@@ -106,6 +106,11 @@ class POPO
     {
         return (object) array('id' => 'parent', 'name' => 'a random name');
     }
+
+    public function getUpperAlias()
+    {
+        return $this->getUpper();
+    }
 }
 
 class ModelToElasticaAutoTransformerTest extends \PHPUnit_Framework_TestCase
@@ -288,6 +293,26 @@ class ModelToElasticaAutoTransformerTest extends \PHPUnit_Framework_TestCase
         $this->assertEquals("a random name", $document->getParent());
     }
 
+    public function testParentMappingWithNullProperty()
+    {
+        $transformer = $this->getTransformer();
+        $document    = $transformer->transform(new POPO(), array(
+            '_parent' => array('type' => 'upper', 'property'=>null, 'identifier' => 'id'),
+        ));
+
+        $this->assertEquals("parent", $document->getParent());
+    }
+
+    public function testParentMappingWithCustomProperty()
+    {
+        $transformer = $this->getTransformer();
+        $document    = $transformer->transform(new POPO(), array(
+            '_parent' => array('type' => 'upper', 'property'=>'upperAlias', 'identifier' => 'id'),
+        ));
+
+        $this->assertEquals("parent", $document->getParent());
+    }
+
     /**
      * @return ModelToElasticaAutoTransformer
      */

Transformer/ModelToElasticaAutoTransformer.php

@@ -63,11 +63,12 @@ class ModelToElasticaAutoTransformer implements ModelToElasticaTransformerInterf
 
         foreach ($fields as $key => $mapping) {
             if ($key == '_parent') {
-                $value = $this->propertyAccessor->getValue($object, $mapping['property']);
+                $property = (null !== $mapping['property'])?$mapping['property']:$mapping['type'];
+                $value = $this->propertyAccessor->getValue($object, $property);
                 $document->setParent($this->propertyAccessor->getValue($value, $mapping['identifier']));
                 continue;
             }
-            
+
             $value = $this->propertyAccessor->getValue($object, $key);
 
             if (isset($mapping['type']) && in_array($mapping['type'], array('nested', 'object'))) {