Dynamic accesor / properties in Laravel 5.8 - php

Question

I'm trying to use dynamic accessor for Laravel model's virtual attributes. Actually I want to handle the situation that if a property doesn't directly exist / doesn't exist in database, load it's value from config file.
I managed to handle it by writing a accessor for each single attribute, but I find it redundant and ugly. I'm sure it can be done more effectively.
class MyModel extends Model
{
public function getTitleAttribute()
{
return $this->loadAttributeFromConfig('title');
}
public function getSubtitleAttribute()
{
return $this->loadAttributeFromConfig('subtitle');
}
public function getTagAttribute()
{
return $this->loadAttributeFromConfig('tag');
}
public function getIconCssClassAttribute()
{
return $this->loadAttributeFromConfig('iconCssClass');
}
public function getBoxCssClassAttribute()
{
return $this->loadAttributeFromConfig('boxCssClass');
}
public function getBulletsAttribute()
{
return $this->loadAttributeFromConfig('bullets');
}
protected function loadAttributeFromConfig($attribute)
{
return config('myConfigAttributes.' . $this->name . '.' . $attribute);
}
}
$myModel->append(['title', 'subtitle', 'tag', 'iconCssClass', 'boxCssClass', 'bullets']);
My solution works but I consider it ugly.

Answer 1

This can actually be achieved rather easily using the __get magic method. You can override it on a base model class that you inherit or create a trait like so:
trait ConfigAttributes
{
/**
* #param string $key
*
* #return mixed
* #throws \Exception
*/
public function __get($key)
{
// Make sure the required configuration property is defined on the parent class
if (!property_exists($this, 'configAttributes')) {
throw new Exception('The $configAttributes property should be defined on your model class');
}
if (in_array($key, $this->configAttributes)) {
return $key;
}
return parent::__get($key);
}
/**
* #return array
*/
public function toArray()
{
// We need to override this method because we need to manually append the
// attributes when serializing, since we're not using Eloquent's accessors
$data = collect($this->configAttributes)->flip()->map(function ($v, $key) {
return $this->loadAttributeFromConfig($key);
});
return array_merge(parent::toArray(), $data->toArray());
}
/**
* #param string $attribute
*
* #return mixed
*/
protected function loadAttributeFromConfig($attribute)
{
return config('myConfigAttributes.' . $this->name . '.' . $attribute);
}
}
Then in you model class just import the trait and specify your custom fields:
class MyModel extends Model
{
use ConfigAttributes;
protected $configAttributes = [
'title',
'subtitle',
'tag',
'iconCssClass',
'boxCssClass',
'bullets'
];
}
Word of caution: be careful when overriding magic methods on classes defined by Laravel, because Laravel makes heavy use of them and if you're not careful you risk breaking other functionality.