如何从 Laravel Eloquent API 资源中仅获取特定字段？

Question

我正在开发一个可通过移动和网络应用程序访问的 API。
我需要从 API 资源发送特定字段。

我有ItemResource

public function toArray($request) {
    return [
        'id'          => $this->id,
        'name'        => $this->name,
        'description' => $this->description,
        'price'       => $this->price,
        'stock'       => $this->stock,
        'reviews'     => $this->reviews, // this is from reviews table
    ];
}

我的Item 模特

public function reviews() {
    return $this->hasMany(ItemReview::class);
}

我的控制器代码

return ItemResource::collection(Item::all());

我得到了这个数组

{
    "data": {
        "id": 10,
        "name": "Item Name",
        "description": "Item description",
        "price": 410,
        "stock": "815",
        "reviews": [
            {
                "id": 4,       // I don't want to get this field
                "item_id": 10, // I don't want to get this field
                "user_id": 9,  // I want to show user name instead of user id
                "review": "item review."
            },
            {
                "id": 12,      // I don't want to get this field
                "item_id": 10, // I don't want to get this field
                "user_id": 3,  // I want to show user name instead of user id
                "review": "item review."
            }
        ]
    }
}

我想得到一个这样的数组

{
    "data": {
        "id": 10,
        "name": "Item Name",
        "description": "Item description",
        "price": 410,
        "stock": "815",
        "reviews": [
            {
                "user_name": 'jhon',  
                "review": "item review."
            },
            {
                "user_name": 'jhon2',  
                "review": "item review."
            }
        ]
    }
}

我只想显示特定字段。
我该如何实现？

Answer 1

1。只有select你需要的东西

如果您在reviews 之后添加括号，您可以返回一个Builder 实例，这将允许您向关系添加查询。
有了这个，你可以select你需要的字段。

public function toArray($request) {
    return [
        'id'          => $this->id,
        'name'        => $this->name,
        'description' => $this->description,
        'price'       => $this->price,
        'stock'       => $this->stock,
        'reviews'     => $this->reviews()->select('user_name', 'review')->get(),
    ];
}

2。创建一个ReviewResource

您还可以为Review 创建一个resource，以返回它自己的数据。

class ReviewResource extends JsonResource
{
    public function toArray($request)
    {
        return [
            'user_name' => $this->user_name,
            'review' => $this->review,
        ];
    }
}

class ItemResource extends JsonResource
{
    public function toArray($request) {
        return [
            'id'          => $this->id,
            'name'        => $this->name,
            'description' => $this->description,
            'price'       => $this->price,
            'stock'       => $this->stock,
            'reviews'     => ReviewResource::collection($this->reviews),
        ];
    }
}