Model attributes are empty, in relationship method, over the api.

[ahmed-osama-saad]

I have relationship defined on WorkoutResults model

public function unfinishedExercises()
    {
        $exercises = $this->exercises();
        $id = $this->id;

        return $exercises->whereDoesntHave('exercisesResults', function ($query) use ($id) {
            $query->where('workout_result_id', $id);
        });
    }

In WorkoutResultSchema, I define the relationship field

HasMany::make('unfinished_exercises', 'unfinishedExercises')->type('exercises'),

The issue I'm facing:

• $this in the unfinishedExercises method is an empty model.
• Consequently, $this->id is null, so the filtering in the whereDoesntHave clause doesn't work as expected.

After some debugging, I found that the problem only occurs when this relationship is requested over the api.
When using the relationship in tinker, $this is defined correctly, and the filtering works as expected.

If I request this relationship from workout-results/:id?include=unfinished_exercise endpoint, the filtering doesn't happen, I get all exercises.

[lindyhopchris]

Hi. Yeah I don't actually think this does work in Tinker. It would need to work via Eager Loading in Tinker.

What happens if yo try this in Tinker:

$models = WorkoutResult::query()->with('unfinishedExercises')->get();

Basically, you can't use $this->id in a relationship method, as the relationships are not always loaded from a specific model - otherwise you'd get N+1 problems.

We use eager loading, so that we don't get N+1 problems.

[efmjackhardcastle]

LaravelJsonAPI package aside, this is bad by design.

    public function unfinishedExercises()
    {
        $exercises = $this->exercises();
        $id = $this->id;

        return $exercises->whereDoesntHave('exercisesResults', function ($query) use ($id) {
            $query->where('workout_result_id', $id);
        });
    }

Should instead be changed to something along these lines:

    // class Exercise
   ... 

    public function WorkoutResult(): BelongsTo
    {
         return $this->belongsTo(WorkoutResult::class);
    }

    public function ExerciseResults(): HasMany
    {
        return $this->hasMany(ExerciseResult::class);
    }

    // class WorkoutResult
    ...
    public function exercises(): HasMany
    {
        return $this->hasMany(Exercise::class);
    }

    public function unfinishedExercises(): HasMany
    {
        return $this->exercises()
            ->whereDoesntHave('exerciseResults');
    }

Without knowing your keys etc can't give a more precise answer.