Php 如何使用Eloquent:：with方法获取特定于数据库的列的嵌套关系？

我有以下三个表格：

发布用户信息

-------------------------------------------------
                     Post
-------------------------------------------------
id | user_id | content | created_at | updated_at

建立的关系如下：

User.php

...
    public function userInfo() {
        return $this->hasOne('App\UserInfo');
    }
...
    public function posts() {
        return $this->hasMany('App\Post');
    }
...

...
    public function user() {
        return $this->belongsTo('App\User');
    }
...

...
    public function user() {
        return $this->belongsTo('App\User');
    }
...

UserInfo.php

...
    public function userInfo() {
        return $this->hasOne('App\UserInfo');
    }
...
    public function posts() {
        return $this->hasMany('App\Post');
    }
...

...
    public function user() {
        return $this->belongsTo('App\User');
    }
...

...
    public function user() {
        return $this->belongsTo('App\User');
    }
...

Post.php

...
    public function userInfo() {
        return $this->hasOne('App\UserInfo');
    }
...
    public function posts() {
        return $this->hasMany('App\Post');
    }
...

...
    public function user() {
        return $this->belongsTo('App\User');
    }
...

...
    public function user() {
        return $this->belongsTo('App\User');
    }
...

我得到的所有帖子都有用户和用户信息嵌套数据，如下所示：

Post::with('user.userInfo')

{
    "data": [
        {
            "id": 1,
            "created_at": "2020-08-01 06:10:00",
            "updated_at": "2020-08-01 06:10:00",
            "user_id": 1,
            "content": "My first post!",
            "user": {
                "id": 1,
                "user_info_id": 1,
                "email": "myemail@gmail.com",
                "username": "derek",
                "access_token": "secret",
                "created_at": "2020-08-01 04:15:09",
                "updated_at": "2020-08-01 04:15:09",
                "user_info": {
                    "id": 1,
                    "user_id": 1,
                    "name": "Derek Baker",
                    "web": "https://github.com/derek90",
                    "birthday": "1990-11-27",
                    "gender": "M",
                    "bio_description": "Software Developer",
                    "profile_picture": null
                }
            }
        },
        {
            "id": 2,
            "created_at": "2020-08-01 06:09:54",
            "updated_at": "2020-08-01 06:09:54",
            "user_id": 1,
            "content": "My second post!",
            "user": {
                "id": 1,
                "user_info_id": 1,
                "email": "myemail@gmail.com",
                "username": "derek",
                "remember_token": null,
                "access_token": "secret",
                "created_at": "2020-08-01 04:15:09",
                "updated_at": "2020-08-01 04:15:09",
                "user_info": {
                    "id": 1,
                    "user_id": 1,
                    "name": "Derek Baker",
                    "web": "https://github.com/derek90",
                    "birthday": "1990-11-27",
                    "gender": "M",
                    "bio_description": "Software Developer",
                    "profile_picture": null
                }
            }
        }
    ]
}

返回如下内容：

Post::with('user.userInfo')

{
    "data": [
        {
            "id": 1,
            "created_at": "2020-08-01 06:10:00",
            "updated_at": "2020-08-01 06:10:00",
            "user_id": 1,
            "content": "My first post!",
            "user": {
                "id": 1,
                "user_info_id": 1,
                "email": "myemail@gmail.com",
                "username": "derek",
                "access_token": "secret",
                "created_at": "2020-08-01 04:15:09",
                "updated_at": "2020-08-01 04:15:09",
                "user_info": {
                    "id": 1,
                    "user_id": 1,
                    "name": "Derek Baker",
                    "web": "https://github.com/derek90",
                    "birthday": "1990-11-27",
                    "gender": "M",
                    "bio_description": "Software Developer",
                    "profile_picture": null
                }
            }
        },
        {
            "id": 2,
            "created_at": "2020-08-01 06:09:54",
            "updated_at": "2020-08-01 06:09:54",
            "user_id": 1,
            "content": "My second post!",
            "user": {
                "id": 1,
                "user_info_id": 1,
                "email": "myemail@gmail.com",
                "username": "derek",
                "remember_token": null,
                "access_token": "secret",
                "created_at": "2020-08-01 04:15:09",
                "updated_at": "2020-08-01 04:15:09",
                "user_info": {
                    "id": 1,
                    "user_id": 1,
                    "name": "Derek Baker",
                    "web": "https://github.com/derek90",
                    "birthday": "1990-11-27",
                    "gender": "M",
                    "bio_description": "Software Developer",
                    "profile_picture": null
                }
            }
        }
    ]
}

我想要的是只获取每个实体的几列，如下所示：

{
    "data": [
        {
            "id": 1,
            "created_at": "2020-08-01 06:10:00",
            "updated_at": "2020-08-01 06:10:00",
            "content": "My first post!",
            "user": {
                "id": 1,
                "username": "derek",
                "user_info": {
                    "name": "Derek Baker",
                    "profile_picture": null
                }
            }
        },
        {
            "id": 2,
            "created_at": "2020-08-01 06:09:54",
            "updated_at": "2020-08-01 06:09:54",
            "content": "My second post!",
            "user": {
                "id": 1,
                "username": "derek",
                "user_info": {
                    "name": "Derek Baker",
                    "profile_picture": null
                }
            }
        }
    ]
}

有没有一种方法可以通过使用

Post:：with

elount函数来实现这一点

我已经尝试了

Post:：with（'user:id，username'，'user.userInfo'）

，它对用户列很有效，但是userInfo提供了它的所有功能

我尝试过的其他事情：

Post:：with（'user:id，username'，'user.userInfo:name，profile\u picture'）

将在json字段中显示

“user\u info”：null

Post:：with（'user:id，username'，'user.userInfo:userInfo.name，userInfo.profile\u picture'）

显示错误

未知列“field list”中的“userInfo.name”

使用

user.userInfo:user.userInfo.name，user.userInfo.profile\u picture

和

user.userInfo:user.user\u info.name，user.user\u info.profile\u picture

可以使用API资源

API资源充当一个转换层，位于 雄辩的模型和实际返回给用户的JSON响应 应用程序的用户

您可以为帖子创建API资源，并在响应中返回帖子的任何位置使用它

Api资源为您提供了更多的控制，您可以操作任何需要的字段，使用几个字段的组合发送一些额外字段，更改响应中需要的字段的名称（

xyz=>$this->name

）

PostResource

<?php

namespace App\Http\Resources;

use Illuminate\Http\Resources\Json\JsonResource;

class PostResource extends JsonResource
{
    public function toArray($request)
    {
        //You can access model properties directly using $this

        return [
            "id" => $this->id,
            "created_at" => $this->created_at,
            "updated_at" => $this->updated_at,
            "content" => $this->content,
            "user" => [
                "id" => $this->user->id,
                "username" => $this->user->username,
                "user_info" => [
                    "name" => $this->user->userInfo->name,
                    "profile_picture" => $this->user->userInfo->profile_picture,
                ]
            ]
        ];
    }
}

如果你有收藏

// $posts is a collection of Post Model instances.

return PostResource::collection($posts);

PostResource将应用于集合中的每个模型实例，然后作为JSON响应返回给您

[注意]

您可以为用户和任何模型创建类似的资源。它使您更容易根据自己的喜好定制响应

同样，在上面的例子中。您可以简单地将user\u info属性仅添加到用户，而不是将user\u info包含在user中

        return [
            "id" => $this->id,
            "created_at" => $this->created_at,
            "updated_at" => $this->updated_at,
            "content" => $this->content,
            "user" => [
                "id" => $this->user->id,
                "username" => $this->user->username,
                "name" => $this->user->userInfo->name,
                "profile_picture" => $this->user->userInfo->profile_picture,
            ]
        ];

---

有趣。谢谢我正在尝试应用这个解决方案，但我必须找出如何使它与排序结果一起工作。（我拥有的是

Post:：with（'user:id，username'，'user.userInfo'）->orderBy（'created_at'，'DESC'）->paginate（10，['page'=>$pageNumber]）

）哦，别担心，你可以直接将分页实例传递给集合方法，就像这样

PostResource:：collection（'paginated_instance）

您可以始终将paginator实例传递给资源的collection方法

是的，我这样做了，但它只返回posts列表。我丢失了->paginate（10）在json数据字段（当前页面等）中包装帖子时提供给我的所有其他文件。我需要这个信息发送到前端，以及知道哪一页的要求。我应该在不同的API资源中添加这些字段吗？不，您不应该单独添加，因为它应该提供文档中提到的meta和link字段。这就是我正在做的：

$posts=Post:：with（'user:id，username'，'user.userInfo'）->orderBy（'created_at'，'DESC'）->paginate（10，['page'=>$pageNumber]）
returnresponse（）->json（PostResource:：collection（$posts），200）