[Serializer] documentation for allow_extra_attributes

juliendidier · juliendidier · commit f4400f30c2a0 · 2016-09-18T12:45:00.000+02:00
diff --git a/components/serializer.rst b/components/serializer.rst
@@ -151,6 +151,28 @@ needs three parameters:
 #. The name of the class this information will be decoded to
 #. The encoder used to convert that information into an array
 
+Extra attributes, attributes which are not mapped to the object, are allowed per default
+by the serializer.
+:method:`Symfony\\Component\\Serializer\\Serializer::deserialize`
+has a fourth parameter, the context. If you want to throw an exception if an attribute is outside
+the object scope, use ``allow_extra_attributes`` as ``false``.
+
+This will throws a :class:`Symfony\Component\Serializer\Exception\ExtraAttributesException` exception,
+because city is not an attribute of ``Acme\Person``::
+
+    $data = <<<EOF
+    <person>
+        <name>foo</name>
+        <age>99</age>
+        <city>Paris</city>
+    </person>
+    EOF;
+
+    $person = $serializer->deserialize($data, 'Acme\Person', 'xml', array(
+        'allow_extra_attributes' => false,
+    ));
+
+
 Deserializing in an Existing Object
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
