Autocomplete Endpoint & Serialization Group

Hey Farry,

Check if you have installed this library in your composer.json file symfony/serializer-pack

Hey Farry,

The AccountController comes with the starting directory of this tutorial. You only have to download the course code and copy that file from the start directory

Cheers!

Hey Mārtiņš C.

Yes you can, you should just pass array of needed values and that's all. But you will need manually iterate your entities and create this array.

Cheers!

Hey Uriel G.

Yeah, that part was made in another tutorial (but part of this track). Here you have the link to it: https://symfonycasts.com/sc...

Cheers!

Hey Adsasd!

I don't know if I totally understand the setup, but I two suggestion, hopefully one will work.

1) Instead of a "placeholder" property, it's legal to have a getPlaceholder() method, which the serializer WILL use, as long as you put it in the right group:

/**
 * @Groups("main")
 */
public function getPlaceholder()
{
    return '...'; // return the placeholder value based on the other properties
}

But this only works if you can calculate the "placeholder" value based on the other properties in your class. I have a feeling that you can't do that... because you probably need to know some outside information (like what's been typed in so far).

2) So... if the above doesn't work, try this, which I actually think is cleaner. I would stop thinking about this API endpoint as returning "Users" and instead imagine that it returns an array of "UserSearchResult"s. Specifically, I would:

A) Create a new model class called UserSearchResult - maybe in src/Model/UserSearchResult.php:

class UserSearchResult
{
    // using public properties to be lazy, but you could make these private and add getters/setters
    public $user;

    public $placeholder;
}
</code<>```


B) In your controller, create an array of *these* objects - something like this:

$users = // some query for the User objects;
$userSearchResults = [];
foreach ($users as $user) {

$result = new UserSearchResult();
$result->user = $user;
$result->placeholder = 'the placeholder'; // do whatever work you need to determine this value

$userSearchResults[] = $users;

}

return $this->json($userSearchResults, ['groups' => ['main']])

So, you are not returning a JSON representation of "UserSearchResult" which will contain the property you need + the normal data for a User.

I hope this helps!

Cheers!

Hey Remus M.!

Haha, sorry! Mostly the fix is to think about what is being serialized, and limit it to only the things you want via groups. Basically, find out *why* there is a circular reference, then avoid serializing the property that causes it.

There is another solution - where you can "handle" the circular reference and take some action - let me know if you need info about that.

Cheers!

if possible, maybe you can provide a solution, when i really need to handle a circular reference, who knows what one might want to serialize with json

Hey Ad F.!

I absolutely can. This is actually a missing feature in Symfony's serializer (easily handling circular reference stuff) - hopefully we'll add it sometime soon. It's a 2 step process. If something doesn't work - let me know - I'm writing this directly into the comment - so it's not tested yet. Also, the way this is done changed in 4.2 slightly. Basically, suppose you're serializing in a controller:

$response = $this->json(
    $someData, 
    200,
    [],
    // the context
    [
        'circular_reference_handler' => function ($object, string $format = null, array $context = array()) {
            return $object->getId();
        })
    ]

This is a bit naive, but basically, when you set this option, instead of an error, this callback is executed. Then, you just return whatever you want to display on that property (instead of it trying to serialize the object again, and getting into a loop). You can't (in Symfony 4.2) configure this option globally, but you can effectively do it by creating some new service that you call, and where that service executes the serializer for your and always passes this option. In ApiPlatform, they implement this automatically and they return the API URL to the given resource - e.g. /api/products/10.

Let me know if it works - or doesn't! If you're on 4.1 or earlier, the solution is slightly different.

Cheers!