php - 当出现一些依赖错误时，如何停止在 Laravel 中执行 Create 操作

Question

我正在根据从用户详细信息表中获取的详细信息创建用户，

我的 Controller

 public function store(Request $request)
    {

// Section 1

 $user = User::create(
            [
                'name' => $request->input('first_name'),
                'email' => $request->input('email'),
                'row_status' => '1',
                'user_type' => '3',
                'password' => bcrypt('RandomPassword@123')

            ]
        );

// Section 2

        $technician_register = new Technician();
        $technician_register->user_id = $user->id;
        $technician_register->first_name = $request->input('first_name');
         if ($request->hasFile('avatar_image')) {
            $avatar_image = $request->file('avatar_image');
            $extension = $avatar_image->getClientOriginalExtension();
            $filename =  $request->input('first_name') . date('Y-M-d') .  '.' . Str::random(3) . "." . $extension;
            $location = public_path('assets/images/technician_avatar/' . $filename);
            Imag::make($avatar_image)->resize(300, 300)->save($location);  // the Image is spelled wrong purposefully to replicate an error.
            $technician_register->avatar_image = $filename;
        }  
        $technician_register->save();

   if ($technician_register) {
        Session::flash('success', 'Selected record has been successfully saved');
        return back();
    } else {
        $user_delete = User::findOrFail($user->id);
        $user_delete->delete();
        Session::flash('error', 'Error');
        return back();

    //This block doesn't seem to work!!
    }

    }

我在执行第 1 部分的第二部分中遇到错误。如果出现任何错误，如何停止或逆转操作的发生

Answer 1

这就是交易非常方便的地方。您可以使用 \DB::beginTransaction()，然后使用 \DB::rollback() 来阻止保存(如果出现问题)，或者 \DB::commit() 完成保存(如果一切顺利)。

基本示例是:

public function store(Request $request){
    \DB::beginTransaction();
    try {
        $user = User::create(
            [
                'name' => $request->input('first_name'),
                'email' => $request->input('email'),
                'row_status' => '1',
                'user_type' => '3',
                'password' => bcrypt('RandomPassword@123')
            ]
        );

        $technician_register = new Technician();

        $technician_register->user_id = $user->id;
        $technician_register->first_name = $request->input('first_name');
        if ($request->hasFile('avatar_image')) {
            $avatar_image = $request->file('avatar_image');
            $extension = $avatar_image->getClientOriginalExtension();
            $filename =  $request->input('first_name') . date('Y-M-d') .  '.' . Str::random(3) . "." . $extension;
            $location = public_path('assets/images/technician_avatar/' . $filename);
            Image::make($avatar_image)->resize(300, 300)->save($location);
            $technician_register->avatar_image = $filename;
        }  

        $technician_register->save();
    } catch (\Exception $ex){
        \Log::error("Error in store(): ".$ex->getMessage());

        \DB::rollBack();

        Session::flash('error', 'Error');
        return back();
    }

    \DB::commit();

    Session::flash('success', 'Selected record has been successfully saved');
    return back();
}

当您使用 DB::beginTransaction 时，结合 try { ... } catch { ... } block ，您可以尝试保存，并且发生错误时(现在已正确捕获，以前没有)，您可以阻止保存数据并防止“困惑”数据(没有相关记录的记录等)

编辑:您有这行代码:

  Imag::make($avatar_image)->resize(300, 300)->save($location);
  // the Image is spelled wrong purposefully to replicate an error.

但是如果没有 try/catch，就会产生 Uncaught Error 并停止执行，这意味着永远不会到达delete 逻辑。