在Laravel工厂模型中添加关系

Question

我正在尝试添加一个工厂模型的关系来做一些数据库种子,如下所示 - 注意我正在尝试为每个用户添加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

我认为它与保存集合有关.如果通过分别调用帖子的每个工厂模型重新编写代码,它似乎工作.显然这不是很优雅,因为如果我想坚持10或发布给每个用户,那么我必须decalare 10或行,除非我使用某种for循环.

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*

有没有什么方法可以将模型工厂嵌套到第3层？

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

试试这个.它对我有用:

factory(\App\Models\Auth\User::class, 300)->create()->each(function ($s) {
                    $s->spots()->saveMany(factory(\App\Models\Spots\Parking::class, 2)->create()->each(function ($u) {
                            $u->pricing()->save(factory(\App\Models\Payment\Pricing::class)->make());
                    }));
                    $s->info()->save(factory(\App\Models\User\Data::class)->make());
            });

Answer 2

对于第 3 级嵌套关系，如果要使用适当的相应外键创建数据，则可以遍历创建帖子的所有结果，如下所示：

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 3

要回答最初的问题/错误消息：

问题确实与保存数据有关。您的代码：

$u->posts()->save(factory(App\Post::class, 2)->make());

...应该改为

$u->posts()->saveMany(factory(App\Post::class, 2)->make());

来自Laravel 文档：

您可以使用 createMany 方法创建多个相关模型：

$user->posts()->createMany( factory(App\Post::class, 3)->make()->toArray());

这意味着：

• 当只用工厂创建一个模型时，你应该使用 save() 或 create()
• 使用工厂创建多个模型时，应使用 saveMany() 或 createMany()

Answer 4

从Laravel 5.6开始，提供了afterCreating和afterMaking回调函数，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。