Double query when using $with in model, and SerializesModels trait

[alexmontoanelli]

Laravel Version

12.x

PHP Version

8.3

Database Driver & Version

No response

Description

If you have a model, with the 'public $with' attribute to autoEagerLoad relationships,
when, unserializing a model in (queue worker, after a job pickup), the Model itself load the relationship ($with attribute), and if the relationship was loaded before the job dispatched, the Trait SerializesAndRestoresModelIdentifiers will load that relationship again.

In my investigations, the SerializesAndRestoresModelIdentifiers::110, is the issue where
he tries to load the relation.

If he use loadMissing, the behavior is OK, no relation already loaded will be loaded.

Steps To Reproduce

class User extends Model {

  public $with = 'country';

  public function country() : HasOne {
    return $this->hasOne(Country::class);
 }

}

class Country extends Model {
}


//load the user
$user = User::find(1);

//$user now has country RelationShip autoloaded loaded


//dispatch a job
$job = new SomeJob($user);

//the model will be serialized
dispatch($job);


//when job is picked up by a worker
//the model with be loaded again from database,
//the $with  will be loaded by the model itset
//the Trait, will reload the relation again (SerializesAndRestoresModelIdentifiers line 110)

[AndrewMast]

So maybe we should ignore the $with when unserializing models? Because when it was serialized it would already have the relationships loaded?

Or maybe we can change SerializesAndRestoresModelIdentifiers.php to use $model->loadMissing() instead of $model->load()?

[alexmontoanelli]

I don't know what is the best strategy, but I will go with change from load() to loadMissing().

We also need to test, if this is happening when serializing a collection ...

[AndrewMast]

I created a repo that reproduces this error: https://github.com/AndrewMast/laravel-testing/tree/issue-55546 (see diff).

Steps to reproduce after cloning:

1. php artisan migrate:fresh --seed
2. php artisan tinker and run User::first()->dispatchTesting();
3. php artisan queue:work to run the dispatched job

As brought up in the issue, these queries are run:

select * from "users" where "users"."id" = 1 limit 1
select * from "countries" where "countries"."id" in (1)
select * from "countries" where "countries"."id" in (1)

When changing load to loadMissing in SerializesAndRestoresModelIdentifiers.php on line 110, it only fetches the country once:

select * from "users" where "users"."id" = 1 limit 1
select * from "countries" where "countries"."id" in (1)

I plan on opening a PR to fix this issue.

[AndrewMast]

@alexmontoanelli This should be fixed with #55547 being merged.

[AndrewMast]

Should be officially fixed with v12.11.0.