laravel APi 资源调用未定义的方法 Illuminate\Database\Query\Builder::mapInto()

Question

我有 Post 和具有一对一关系的用户模型并且效果很好：

//User.php

public function post(){
    return $this->hasOne(Post::class);
}


// Post.php

public function user() {
    return $this->belongsTo(User::class);
}

现在我创建 API 资源：

php artisan make:resource Post
php artisan make:resource User

我需要 return 所有 post 与 api 呼叫然后我设置我的路线：

//web.php: /resource/posts

Route::get('/resource/posts', function () {
    return PostResource::collection(Post::all());
});

这是我的 Post 资源 class:

<?php

namespace App\Http\Resources;
use Illuminate\Http\Resources\Json\Resource;
use App\Http\Resources\User as UserResource;

class Posts extends Resource
{
/**
 * Transform the resource into an array.
 *
 * @param  \Illuminate\Http\Request  $request
 * @return array
 */
public function toArray($request)
{
      return [
        'id' => $this->id,
        'title' => $this->title,
        'slug' => $this->slug,
        'bodys' => $this->body,
        'users' => UserResource::collection($this->user),
        'published' => $this->published,
        'created_at' => $this->created_at,
        'updated_at' => $this->updated_at,
    ];

}
}

这是错误：

Call to undefined method Illuminate\Database\Query\Builder::mapInto()

如果我删除：

'users' => UserResource::collection($this->user),

它的工作，但我需要在我的 api json 中包含关系，我已经阅读并遵循 https://laravel.com/docs/5.5/collections 上的文档。

这是我的用户资源 class:

```

namespace App\Http\Resources;

use Illuminate\Http\Resources\Json\Resource;

class User extends Resource
{
/**
 * Transform the resource into an array.
 *
 * @param  \Illuminate\Http\Request  $request
 * @return array
 */
public function toArray($request)
{
   return [
       'user_id' => $this->user_id,
       'name' => $this->name,
       'lastname' => $this->lastname,
       'email' => $this->email
   ];
}
}

有什么想法我哪里错了吗？

Answer 1

问题是您使用 UserResource::collection($this->user) 并且只有一个元素不是集合，因此您可以像这样用 new UserResource($this->user) 替换它：

return [
    'id' => $this->id,
    'title' => $this->title,
    'slug' => $this->slug,
    'bodys' => $this->body,
    'users' => new UserResource($this->user),
    'published' => $this->published,
    'created_at' => $this->created_at,
    'updated_at' => $this->updated_at,
];

Answer 2

这个问题是你使用 UserResource::collection($this->user) 这意味着你有很多用户但是你只有一个元素而不是一个集合所以你可以用 new UserResource($this ->用户)

Answer 3

在Laravel 8.5.*中，可以对集合使用静态方法make得到相同的结果。就像 UserResource::make($this->user)

laravel APi 资源调用未定义的方法 Illuminate\Database\Query\Builder::mapInto()

laravel APi resource Call to undefined method Illuminate\Database\Query\Builder::mapInto()

api

laravel

laravel-5.5