src/Eloquent/Concerns/SerializesModels.php
protected function attributeKeys(Model $model)
    {
        if (is_array($this->attributes)) {
            return $this->attributes;
        }

        return $model->getVisible();
    }
protected function attributeKeys(Model $model)
    {
        if (is_array($this->attributes)) {
            return $this->attributes;
        }

        return $model->getVisible();
    }
Get the attributes to serialize for the provided model.

@param Model $model
@return array