Laravel Relationship Events

Packages

July 9th, 2018

Laravel Relationship Events

Laravel Relationship Events is a package by Viacheslav Ostrovskiy that adds extra model relationship events. This package comes with the following traits that are used to register listeners on a model’s boot() method:

  • HasOneEvents
  • HasBelongsToEvents
  • HasManyEvents
  • HasBelongsToManyEvents
  • HasMorphOneEvents
  • HasMorphToEvents
  • HasMorphManyEvents
  • HasMorphToManyEvents
  • HasMorphedByManyEvents

And from the above traits, here’s an example of a few events on a Country model that has many Users using the HasManyEvents trait:

namespace App\Models;
 
use App\User;
use Chelout\RelationshipEvents\Concerns\HasManyEvents;
use Illuminate\Database\Eloquent\Model;
 
class Country extends Model
{
use HasManyEvents;
 
protected $fillable = [
'name',
];
 
public function users()
{
return $this->hasMany(User::class);
}
 
public static function boot()
{
parent::boot();
 
static::hasManySaving(function ($parent, $related) {
Log::info("Saving user's country {$parent->name}.");
});
 
static::hasManySaved(function ($parent, $related) {
Log::info("User's country is now set to {$parent->name}.");
});
}
}

And the inverse of the relationship with this package might look like the following:

namespace App\Models;
 
use Illuminate\Database\Eloquent\Model;
use Chelout\RelationshipEvents\Concerns\HasBelongsToEvents;
 
class User extends Model
{
use HasBelongsToEvents;
 
/**
* Get the country associated with the user.
*/
public function country()
{
return $this->belongsTo(Country::class);
}
 
protected static function boot()
{
parent::boot();
 
static::belongsToAssociating(function ($relation, $related, $parent) {
Log::info("Associating country {$parent->name} with user.");
});
 
static::belongsToAssociated(function ($relation, $related, $parent) {
Log::info("User has been assosiated with country {$parent->name}.");
});
}
}

Using an overloaded associate() method, you can fire two events belongsToAssociating and belongsToAssociated:

$country = App\Models\Country::first();
 
$user = factory(User::class)->create([
'name' => 'John Smith',
]);
 
// Assosiate user with country
// This will fire belongsToAssociating and belongsToAssociated events
$user->country()->associate($country);

Learn More

The package has documentation for each trait and association type. Check out the package on GitHub at chelout/laravel-relationship-events.

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Paul Redmond

Full stack web developer. Author of Lumen Programming Guide and Docker for PHP Developers.