Symfony - Deserialize json to an array of entities - php

Question

I have a json object that I received by making a get API call. I make this call to receive a list of objects. It's a list of post... So I have an array of Post Objects.
Here the output :
{
"total":2,
"data":[
{
"id":2,
"user":{
"id":1,
"username":"sandro.tchikovani"
},
"description":"cool",
"nb_comments":0,
"nb_likes":0,
"date_creation":"2014-04-13T20:07:34-0700"
},
{
"id":1,
"user":{
"id":1,
"username":"sandro.tchikovani",
},
"description":"Premier pooooste #lol",
"nb_comments":0,
"nb_likes":0,
"date_creation":"2014-04-13T15:15:35-0700"
}
]
}
I would like to deserialize the data part...
The problem is that the Serializer in Symfony gives me an error ...
The error that I have :
Class array<Moodress\Bundle\PosteBundle\Entity\Poste> does not exist
How I do deserialize :
$lastPosts = $serializer->deserialize($data['data'], 'array<Moodress\Bundle\PosteBundle\Entity\Poste>', 'json');
How can I deserialze the data array... To have an array of Postes. I want to give to my view .twig an array Poste... I did precise the type when I deserialize... So I can't find what is the problem...
Thanks.

Answer 1

I think the best solution here is to create new PosteResponse class, like this one:
namespace Moodress\Bundle\PosteBundle\Response;
use JMS\Serializer\Annotation\Type;
class PosteResponse
{
/**
* #Type("integer")
*/
private $total;
/**
* #Type("array<Moodress\Bundle\PosteBundle\Entity\Poste>")
*/
private $data;
//getters here
}
and deserialize your response to that class:
$response = $serializer->deserialize(
$json,
'Moodress\Bundle\PosteBundle\Response\PosteResponse',
'json'
);
$posts = $response->getData();
That WILL do the trick, and it doesn't require you to decode and encode your json manually which is riddiculous in my opinion.

Answer 2

Since Symfony Serializer Component 2.8 to deserialize array of objects:
$persons = $serializer->deserialize($data, 'Acme\Person[]', 'json');
https://symfony.com/doc/master/components/serializer.html#handling-arrays

Answer 3

A less than ideal solution that I found was to first decode and then encode the json data again at the node that represents the data array. For example in your case:
$json = json_decode($json);
$json = json_encode($json->data);
$serializer->deserialize($json, 'array<Moodress\Bundle\PosteBundle\Entity\Poste>', 'json');
There must be a better solution than this but this seems more elegant than the above solution of de-serialising json.

Answer 4

The error is pretty clear. Your string does not match any existant class.
The example in official documentation says:
$person = $serializer->deserialize($data,'Acme\Person','xml');
In your case it should be more like:
$person = $serializer->deserialize($data['data'],'Moodress\Bundle\PosteBundle\Entity\Poste','json');
Update:
Ok then.
First, your json file does not seem to be valid (use http://jsonlint.com/ to test it). Be careful of that.
Second, you will have to fetch your json as an array with
$data = json_decode($yourJsonFile, true);
and then you can access to each 'data' array with
foreach($data['data'] as $result)
{
/* Here you can hydrate your object manually like:
$person = new Person();
$person->setId($user['id']);
$person->setDescription($user['description']);
Or you can use a denormalizer. */
}

Answer 5

I would make something like this
class PostsModel
{
/**
* #var int
*/
private $total;
/**
* #var PostModel[]
*/
private $data;
}
class PostModel
{
/**
* #var int
*/
private $id;
/**
* #var UserModel
*/
private $user;
/**
* #var string
*/
private $description;
/**
* #var int
*/
private $nb_comments;
/**
* #var int
*/
private $nb_likes;
/**
* #var \DateTime
*/
private $date_creation;
}
class UserModel
{
/**
* #var int
*/
private $id;
/**
* #var string
*/
private $username;
}
And in controller
$posts = $this->serializer->deserialize($data, PostsModel::class, 'json');
And this will return $postsModel with $data property which will have your array of entities

Answer 6

In case someone will be searching how to decode an array of objects using Symfony Serializer:
use Moodress\Bundle\PosteBundle\Entity\Poste;
// your json data
$data = '{
"total":2,
"data":[
{...},
{...}
]
}';
$lastPosts = $serializer->deserialize(
$data['data'],
'Poste[]', // or Poste::class.'[]',
'json'
);
Notice that you need to add [] after your class name, in this way Symfony will recognize your json data as an array of objects.