Laravel 事件阻止更新模型

Laravel event prevent updating a model

我有一个 Conversation 可以设置为私人。设置为私有意味着 conversations 上的 user_id 将被分配一个非空值。如果他有足够的积分,用户可以将对话设置为私人。

前端拥有验证逻辑,但我也想在后端进行。

我已将事件设置为在模型保存时触发:

protected $dispatchesEvents = [
    'saving' => ConversationSaving::class,
];

那个事件没什么特别的:

public function __construct(Conversation $conversation)
{
    Log::info("[Event] " . get_class());
    $this->conversation = $conversation;
}

事件服务提供者的逻辑是这样的:

ConversationSaving::class      => [
    PreventMakingPrivate::class
],
ConversationMadePrivate::class => [
    DeductCreditsForMakingPrivate::class
],

这个想法是触发更新,如果更新失败,ConversationMadePrivate 事件永远不会触发。

控制器看起来像这样:

$conversation->update(['user_id' => Auth::user()->id]);

Log::info('After update');
Log::info($conversation->user_id);
Log::info($conversation->user_id ? 't':'f');

if(!$conversation->user_id){
    return response([
        'error' => 'Error making private',
    ]);
}

event(new ConversationMadePrivate($conversation));

return response([
    'conversation' => $conversation->load('messages'),
]);

现在我在日志中得到的是:

[2020-05-16 07:34:41] local.INFO: [Event] App\Events\ConversationSaving 
[2020-05-16 07:34:41] local.INFO: [Listener] App\Listeners\PreventMakingPrivate  
[2020-05-16 07:34:41] local.INFO: [Listener] Not enough credits  
[2020-05-16 07:34:41] local.INFO: After update  
[2020-05-16 07:34:41] local.INFO: 1  
[2020-05-16 07:34:41] local.INFO: t  
[2020-05-16 07:34:41] local.INFO: [Event] App\Events\ConversationMadePrivate  
[2020-05-16 07:34:41] local.INFO: [Listener] App\Listeners\DeductCreditsForMakingPrivate  

因此代码从 PreventMakingPrivate 正确进入侦听器和 returns false,但模型仍在更新。

我也试过设置 Conversation updating 而不是 saving,但同样的事情发生了。

如何阻止更新?

哦,我明白了。如果有人也需要它,看起来 update 方法将 return 1 成功,否则没有。这解决了我的问题:

$response = $conversation->update(['user_id' => Auth::user()->id]);

if(!$response){
    return response([
        'error' => 'Error making private',
    ]);
}