Public property with scoped relation doesn't persist between requests

#1

What seems to be the problem:

I used this great article (https://reinink.ca/articles/dynamic-relationships-in-laravel-using-subqueries) to help me include the single latest relation.

It uses a scope query on my model. That works absolutely fine, but when I submit my form the public property seems to lose the scoped relation but everything else persists.

Steps to Reproduce:

Are you using the latest version of Livewire:

^1.0

Do you have any screenshots or code examples:

public function updatedToTank()
{
    $this->transit = 
        Tank::withLastEvent()
            ->with('site')
            ->identifier($this->toTank)
            ->site($this->site()->id)
            ->first();
}

when the toTank field changes I fetch the relevant model, this works well because it only runs after my validateOnly call is successful in the main updated method.

But when I submit the form which is a new Livewire request, then try to access transit->lastEvent it is null in my submit handler method, so the scoped relation isn’t persisted.

I should note that the normal with(‘site’) works fine, I can access transit->site inside the submit handler.

Can anyone help or has anyone seen this before? Many thanks.

#2

This is likely happening because javascript cannot read PHP objects. When livewire exposes your public variables after refresh, it needs to cast them as something javascript can read: string, int, array, etc. That’s why some of the accessors will work: $transit->site might be a string but $transit->lastEvent might be a model which javascript cannot work with. You’ll likely have to rethink how you’re passing information based on this. Loading $transit as an array that javascript can read with the information that you need would be one way of accomplishing this. Another might be to have a nested component access the lastEvent based on an id.

#3

Hi, thanks for your response.

Sorry but I don’t think that’s quite right - $transit->site is an Eloquent model and it is persisted. When I dd $transit it has a relations member which contains site, and is also where lastEvent is null.

Also from the docs: “Properties can ONLY be either a JavaScript-friendly data types (string , int , array , boolean), OR an eloquent model (or collection of models).”