--- /dev/null
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Serializer\Mapping\Loader;
+
+use Symfony\Component\Serializer\Exception\MappingException;
+use Symfony\Component\Serializer\Mapping\AttributeMetadata;
+use Symfony\Component\Serializer\Mapping\ClassMetadataInterface;
+use Symfony\Component\Yaml\Parser;
+
+/**
+ * YAML File Loader.
+ *
+ * @author Kévin Dunglas <dunglas@gmail.com>
+ */
+class YamlFileLoader extends FileLoader
+{
+ private $yamlParser;
+
+ /**
+ * An array of YAML class descriptions.
+ *
+ * @var array
+ */
+ private $classes = null;
+
+ /**
+ * {@inheritdoc}
+ */
+ public function loadClassMetadata(ClassMetadataInterface $classMetadata)
+ {
+ if (null === $this->classes) {
+ if (!stream_is_local($this->file)) {
+ throw new MappingException(sprintf('This is not a local file "%s".', $this->file));
+ }
+
+ if (null === $this->yamlParser) {
+ $this->yamlParser = new Parser();
+ }
+
+ $classes = $this->yamlParser->parse(file_get_contents($this->file));
+
+ if (empty($classes)) {
+ return false;
+ }
+
+ // not an array
+ if (!is_array($classes)) {
+ throw new MappingException(sprintf('The file "%s" must contain a YAML array.', $this->file));
+ }
+
+ $this->classes = $classes;
+ }
+
+ if (!isset($this->classes[$classMetadata->getName()])) {
+ return false;
+ }
+
+ $yaml = $this->classes[$classMetadata->getName()];
+
+ if (isset($yaml['attributes']) && is_array($yaml['attributes'])) {
+ $attributesMetadata = $classMetadata->getAttributesMetadata();
+
+ foreach ($yaml['attributes'] as $attribute => $data) {
+ if (isset($attributesMetadata[$attribute])) {
+ $attributeMetadata = $attributesMetadata[$attribute];
+ } else {
+ $attributeMetadata = new AttributeMetadata($attribute);
+ $classMetadata->addAttributeMetadata($attributeMetadata);
+ }
+
+ if (isset($data['groups'])) {
+ if (!is_array($data['groups'])) {
+ throw new MappingException(sprintf('The "groups" key must be an array of strings in "%s" for the attribute "%s" of the class "%s".', $this->file, $attribute, $classMetadata->getName()));
+ }
+
+ foreach ($data['groups'] as $group) {
+ if (!is_string($group)) {
+ throw new MappingException(sprintf('Group names must be strings in "%s" for the attribute "%s" of the class "%s".', $this->file, $attribute, $classMetadata->getName()));
+ }
+
+ $attributeMetadata->addGroup($group);
+ }
+ }
+ }
+ }
+
+ return true;
+ }
+}