Eager Loading not working with BelongsTo

[SeoFood]

Resource:

public static $with = [ 'address'];

public function fields(Request $request)
{
  BelongsTo::make('Address')->searchable(),
}

Result:

If I use computed fields manually its working.

[Quinndark]

I had the same problem.

[Livijn]

+1

[ragingdave]

This is also found on morphTo as well

[taylorotwell]

I need you to describe your resource / table structure a bit more. Your code snippet is really out of context so it's hard for me to tell how to recreate things.

[BengtHagemeister]

I have a simulier issue with the following output from debugbar:

Page URL: http://nova.test/resources/coupling-equipments?coupling-equipments_page=2

API URL: http://nova.test/nova-api/coupling-equipments?search=&filters=&orderBy=&orderByDirection=desc&perPage=25&trashed=&page=2&viaResource=&viaResourceId=&viaRelationship=&relationshipType=

Nove Resource CouplingEquipment:

class CouplingEquipment extends Resource {

     ....

     public static $with = ['couplingSize'];

     public function fields(Request $request)
         {
             return [
                 BelongsTo::make('Kupplung', 'couplingSize', CouplingSize::class),
             ];
         }

     ....

}

Nova Resource CouplingSize:

class CouplingSize extends Resource {

     ....

     public function fields(Request $request)
     {

          return [
               HasMany::make('couplingEquipment'),
          ]
     }

     ....

}

Model CouplingEquipment:

class CouplingEquipment extends Model {

     public function couplingSize()
         {
             return $this->belongsTo(CouplingSize::class);
         }
}

Model CouplingSize:

class CouplingSize extends Model {

     public function couplingEquipment()
    {
        return $this->hasMany(CouplingEquipment::class);
    }

}

Table structure:

• coupling_equipment

  • id (int)
  • coupling_size_id (int) -> relationship to coupling_size

• coupling_sizes

  • id (int)

[caseydwyer]

We're seeing this issue as well. One note, it doesn't appear to be an issue on initial index page-load.

For example, we have a School model & resource, that's a simple BelongsTo relationship with StudentOrganization. There are ~250 Schools and ~250 StudentOrganizations. When visiting the Schools resource page initially (/resources/schools), it loads quickly, without unnecessary queries (analyzing with Laravel Debugbar).

When that URL gains any parameter, though, it starts running several hundred queries, many duplicate. This includes pagination, filter, sorting and search parameters. Hope that helps.

[abordage]

When that URL gains any parameter, though, it starts running several hundred queries, many duplicate. This includes pagination, filter, sorting and search parameters. Hope that helps.

+1, same problem

[mikebouwmans]

I'm actually having the same problem, but for me all pages won't load anymore when eager loading with all relations.

[markgp]

We made the following changes to /nova/src/Fields/BelongsTo.php which solved the issue for us.

You still need to define your relationships using the $with property, obviously.

--- a/BelongsTo.php     2018-10-26 13:54:48.552145700 +1100
+++ b/BelongsTo.php     2018-10-26 13:53:20.778856800 +1100
@@ -144,7 +144,7 @@
      */
     public function resolve($resource, $attribute = null)
     {
-        $value = $resource->{$this->attribute}()->withoutGlobalScopes()->first();
+        $value = $resource->{$this->attribute};

         if ($value) {
             $this->belongsToId = $value->getKey();

[abordage]

@markgp , https://github.com/laravel/nova-issues/issues/246#issuecomment-420939582

[jasonlav]

Also able to verify issue. Belongs to will eager load and proceed to query each relationship.

[Etmolf]

We made the following changes to /nova/src/Fields/BelongsTo.php which solved the issue for us.

You still need to define your relationships using the $with property, obviously.

--- a/BelongsTo.php     2018-10-26 13:54:48.552145700 +1100
+++ b/BelongsTo.php     2018-10-26 13:53:20.778856800 +1100
@@ -144,7 +144,7 @@
      */
     public function resolve($resource, $attribute = null)
     {
-        $value = $resource->{$this->attribute}()->withoutGlobalScopes()->first();
+        $value = $resource->{$this->attribute};

         if ($value) {
             $this->belongsToId = $value->getKey();

For a temporary workaround that does not break updates: make a new action and extend the existing BelongsTo Class in your FieldClass:

php artisan nova:field acme/belongs-to-field

use Laravel\Nova\Fields\BelongsTo;

class BelongsToField extends BelongsTo
{
    /**
     * Resolve the field's value.
     *
     * @param  mixed  $resource
     * @param  string|null  $attribute
     * @return void
     */
    public function resolve($resource, $attribute = null)
    {
        $value = $resource->{$this->attribute};

        if ($value) {
            $this->belongsToId = $value->getKey();

            $this->value = $this->formatDisplayValue($value);
        }
    }
}

You can skip all the node dependencies and resources as the existing nova component will be used.

Change all uses of "BelongsTo" to your own "BelongsToField". If a proper fix is available, just change it back to the nova one.

[bomshteyn]

Thanks @Etmolf ,

Since we would have todo this in few projects, i have created an installable package based on your code. Belongs To field that respects Eager Loading

[dillingham]

Just noticed this also, any updates?

$value = $resource->{$this->attribute}()->withoutGlobalScopes()->first();

being changed to the following does seem to work as stated above

$value = $resource->{$this->attribute};

[huoding]

+1, I have the same question.

[dkulyk]

PR was sent to upstream.

[dkulyk]

This has been fixed and will be included in the next release.

[fedeisas]

@dkulyk ETA for the next release, please. Thanks.

[davidhemphill]

Soon, once we get docs for the new version out. You can use dev-master right now though.

[caseydwyer]

@davidhemphill Thanks for the updates! Really appreciate your responsiveness, and really looking forward to this update. 👍

[nouman-ashraf-awan]

This is my relation in Group Model

/** @return BelongsToMany */
    public function currencies()
    {
        return $this->belongsToMany(Currency::class, CurrencyGroup::class, 'group_id', 'currency_id')
            ->withPivot('id', 'amount', 'remaining', 'type', 'begins_at', 'expires_at', 'contract_id')
            ->withTimestamps('created_at', 'updated_at');
    } 
``` In Group Nova Resource 
BelongsToMany::make('Assigned Currencies', 'currencyContracts', Currency::class)
                ->fields(new CurrencyContractFields)
                ->allowDuplicateRelations()
                ->canSee(fn () => Setting::get('ff_enable_currency_system'))
In CurrencyGroup Model which is pivot of Currency 
I have a relation currencyUsers

public function currencyUsers() { return $this->hasMany(CurrencyUser::class, 'currency_group_id', 'id'); }

Eager loading only working with nova-api/groups/ID 
but not in 
/nova-api/currencies?orderBy=&page=1&perPage=5&relationshipType=belongsToMany&search=&trashed=&viaRelationship=currencies&viaResource=groups&viaResourceId=ID
I want to eager load currencyUsers in Group.php Nova. I have included in $with=['currencies.pivot.currencyUsers']; but this is causing N+1 Problem. How can i achieve eager loading in Group.php Nova Resource.

[Quinndark]

您好，邮件已收到，谢谢。。