Parse REST Json replay

Question

I create a views with REST export display, result are serialized with Json,

In my formBuild method I want to parse JSON and Convert it to array and use it in select option

    $host = \Drupal::request()->getHost();
    $response = \Drupal::httpClient()
        ->get($host.'/get/slider' );

    $json_string = $response->getBody()->getContents();
    kint($json_string);

I see Symfony serialize class and find Deserialize method with this example

 $person = $serializer->deserialize($data, 'Acme\Person', 'xml');

According to this,I guess maybe I should something like

     $results = $serializer->deserialize($json_string, '???', 'josn');

but what I should write in second param(???)? I try

    $serialize = new Serializer\Serializer();
    $json_string = $response->getBody()->getContents();
  $entity = $serialize->deserialize($json_string, '\Drupal\node\Entity\Node::class', 'json')  ;

but face me with error Symfony\Component\Serializer\Exception\UnexpectedValueException: Deserialization for the format json is not supported in Symfony\Component\Serializer\Serializer->deserialize().

And if you have better solution tell me How Can I deserilized views REST results?

update Also,I tried

    $json_string = $response->getBody()->getContents();
    $serializer = \Drupal::service('serializer');
    $deserialized = $serializer->deserialize($json_string, \Drupal\node\Entity\Node::class, 'json');

but Symfony\Component\Serializer\Exception\UnexpectedValueException: A string must be provided as a bundle value. in Drupal\serialization\Normalizer\EntityNormalizer->denormalize()

Answer 1

Drupal has a service for serialisation, pre-configured with the normalisers and encoders you need. The error you currently have is because you're not setting up the instance of the serialiser with the Symfony\Component\Serializer\Encoder\JsonEncoder, but you'll also need, for example, the Drupal\serialization\Normalizer\ConfigEntityNormalizer normaliser.

This code works well for me:

$serializer = \Drupal::service('serializer');
$node = \Drupal::entityTypeManager()->getStorage('node')->load(1);

$output = $serializer->serialize($node, 'json');
$deserialized_node = $serializer->deserialize($output, \Drupal\node\Entity\Node::class, 'json');

As always, inject the services if possible.

Answer 2

Try json_decode, first use Drupal\Core\Serializer;

then in your code use

 $json_string = $response->getBody()->getContents();  
 $res =json_decode($json_string);