relationship - 向Laravel Factory模型添加关系

Question

我试图添加与工厂模型的关系以进行一些数据库播种，如下所示-注意，我试图向每个用户添加2个帖子

public function run()
{
   factory(App\User::class, 50)->create()->each(function($u) {
         $u->posts()->save(factory(App\Post::class, 2)->make());
   });
}

但是它抛出以下错误

Argument 1 passed to Illuminate\Database\Eloquent\Relations\HasOneOrMany::s  
ave() must be an instance of Illuminate\Database\Eloquent\Model, instance 
of Illuminate\Database\Eloquent\Collection given

我认为这与保存收藏夹有关。如果通过分别调用该帖子的每个工厂模型来重写代码，那么它似乎可以工作。显然，这不是很优雅，因为如果我想保留10个或向每个用户发布内容，那么除非我使用某种for循环，否则我必须减少10个或10行。

public function run()
{
   factory(App\User::class, 50)->create()->each(function($u) {
     $u->posts()->save(factory(App\Post::class)->make());
     $u->posts()->save(factory(App\Post::class)->make());
   });
}

*更新*

有什么方法可以将模型工厂嵌套到第三层深度？

public function run()
{
   factory(App\User::class, 50)
       ->create()
       ->each(function($u) {
           $u->posts()->saveMany(factory(App\Post::class, 2)
                    ->make()
                    ->each(function($p){
                          $p->comments()->save(factory(App\Comment::class)->make());
          }));
   });
}

Answer 1

从Laravel 5.6开始，有一个回调函数afterCreating & afterMaking允许您在创建/制作之后直接添加关系:

$factory->afterCreating(App\User::class, function ($user, $faker) {
    $user->saveMany(factory(App\Post::class, 10)->make());
});

$factory->afterMaking(App\Post::class, function ($post, $faker) {
    $post->save(factory(App\Comment::class)->make());
});

现在

factory(App\User::class, 50)->create()

将为您提供50位用户，每位用户有10条帖子，每条帖子都有一条评论。