Laravel Pivot

This package introduces new eloquent events for sync(), attach(), detach() or updateExistingPivot() methods on BelongsToMany relation.

Laravel Problems

In Laravel events are not dispatched when BelongsToMany relation (pivot table) is updated with sync(), attach(), detach() or updateExistingPivot() methods, but this package will help with that.

Version Compatibility

Laravel Version	Package Tag	Supported	Development Branch
>= 5.5.0	3.*	yes	master
< 5.5.0	-	no	-

• you still can use inactive branches for laravel 5.4.x or older

Install

1.Install package with composer

composer require fico7489/laravel-pivot

With this statement, a composer will install highest available package version for your current laravel version.

2.Use Fico7489\Laravel\Pivot\Traits\PivotEventTrait trait in your base model or only in particular models.

...
use Fico7489\Laravel\Pivot\Traits\PivotEventTrait;
use Illuminate\Database\Eloquent\Model;

abstract class BaseModel extends Model
{
    use PivotEventTrait;
...

and that's it, enjoy.

New eloquent events

You can check all eloquent events here: https://laravel.com/docs/5.5/eloquent#events)

New events are :

pivotAttaching, pivotAttached
pivotDetaching, pivotDetached,
pivotUpdating, pivotUpdated

The best way to catch events is with this model functions :

public static function boot()
{
    parent::boot();

    static::pivotAttaching(function ($model, $relationName, $pivotIds, $pivotIdsAttributes) {
        //
    });
    
    static::pivotAttached(function ($model, $relationName, $pivotIds, $pivotIdsAttributes) {
        //
    });
    
    static::pivotDetaching(function ($model, $relationName, $pivotIds) {
        //
    });

    static::pivotDetached(function ($model, $relationName, $pivotIds) {
        //
    });
    
    static::pivotUpdating(function ($model, $relationName, $pivotIds, $pivotIdsAttributes) {
        //
    });
    
    static::pivotUpdated(function ($model, $relationName, $pivotIds, $pivotIdsAttributes) {
        //
    });
    
    static::updating(function ($model) {
        //this is how we catch standard eloquent events
    });
}

You can also see those events here :

\Event::listen('eloquent.*', function ($eventName, array $data) {
    echo $eventName;  //e.g. 'eloquent.pivotAttached'
});

Suported relations

BelongsToMany and MorphToMany

Which events are dispatched and when they are dispatched

Four BelongsToMany methods dispatches events from this package :

attach()
Dispatches one pivotAttaching and one pivotAttached event.
Even when more rows are added only one event is dispatched for all rows but in that case, you can see all changed row ids in the $pivotIds variable, and the changed row ids with attributes in the $pivotIdsAttributes variable.

detach()
Dispatches one pivotDetaching and one pivotDetached event.
Even when more rows are deleted only one event is dispatched for all rows but in that case, you can see all changed row ids in the $pivotIds variable.

updateExistingPivot()
Dispatches one pivotUpdating and one pivotUpdated event.
You can change only one row in the pivot table with updateExistingPivot.

sync()
Dispatches more pivotAttaching and more pivotAttached events, depending on how many rows are added in the pivot table. These events are not dispatched if nothing is attached.
Dispatches one pivotDetaching and one pivotDetached event, but you can see all deleted ids in the $pivotIds variable. This event is not dispatched if nothing is detached.
E.g. when you call sync() if two rows are added and two are deleted two pivotAttaching and two pivotAttached events and one pivotDetaching and one pivotDetached event will be dispatched.
If sync() is called but rows are not added or deleted events are not dispatched.

Usage

We have three tables in database users(id, name), roles(id, name), role_user(user_id, role_id). We have two models :

...
class User extends Model
{
    use PivotEventTrait;
    ....
    
    public function roles()
    {
        return $this->belongsToMany(Role::class);
    }
    
    static::pivotAttached(function ($model, $relationName, $pivotIds, $pivotIdsAttributes) {
        echo 'pivotAttached';
        echo get_class($model);
        echo $relationName;
        print_r($pivotIds);
        print_r($pivotIdsAttributes);
    });
    
    static::pivotUpdated(function ($model, $relationName, $pivotIds, $pivotIdsAttributes) {
        echo 'pivotUpdated';
        echo get_class($model);
        echo $relationName;
        print_r($pivotIds);
        print_r($pivotIdsAttributes);
    });
    
    static::pivotDetached(function ($model, $relationName, $pivotIds) {
        echo 'pivotDetached';
        echo get_class($model);
        echo $relationName;
        print_r($pivotIds);
    });

...
class Role extends Model
{
    ....

Attaching

For attach() or detach() one event is dispatched for both pivot ids.

Attaching with int

Running this code

$user = User::first();
$user->roles()->attach(1);

You will see this output

pivotAttached
App\Models\User
roles
[1]
[1 => []]

Attaching with array

Running this code

$user = User::first();
$user->roles()->attach([1]);

You will see this output

pivotAttached
App\Models\User
roles
[1]
[1 => []]

Attaching with model

Running this code

$user = User::first();
$user->roles()->attach(Role::first());

You will see this output

pivotAttached
App\Models\User
roles
[1]
[1 => []]

Attaching with collection

Running this code

$user = User::first();
$user->roles()->attach(Role::get());

You will see this output

pivotAttached
App\Models\User
roles
[1, 2]
[1 => [], 2 => []]

Attaching with array (id => attributes)

Running this code

$user = User::first();
$user->roles()->attach([1, 2 => ['attribute' => 'test']], ['attribute2' => 'test2']);

You will see this output

pivotAttached
App\Models\User
roles
[1, 2]
[1 => [], 2 => ['attribute' => 'test', 'attribute2' => 'test2']]

Syncing

For sync() method event is dispatched for each pivot row.

Running this code

$user = User::first();
$user->roles()->sync([1, 2]);

You will see this output

pivotAttached
App\Models\User
roles
[1]
[1 => []]

pivotAttached
App\Models\User
roles
[2]
[2 => []]

Detaching

Running this code

$user = User::first();
$user->roles()->detach([1, 2]);

You will see this output

pivotAttached
App\Models\User
roles
[1, 2]

Updating

Running this code

$user = User::first();
$user->roles()->updateExistingPivot(1, ['attribute' => 'test']);

You will see this output

pivotUpdated
App\Models\User
roles
[1]
[1 => ['attribute' => 'test']]

License

MIT

Free Software, Hell Yeah!