package main

import (
	"fmt"

	"github.com/gogf/gf/v2/util/gconv"
)

func main() {
	req := map[string]any{
		"id": "123",
		"doc": map[string]any{
			"craft": nil,
		},
		"fields": []string{"_id"},
	}

	var args *UpdateByIdReq
	err := gconv.Struct(req, &args)
	if err != nil {
		panic(err)
	}
	fmt.Printf("%T", args.Doc["craft"])
}

type UpdateByIdReq struct {
	Id     string                 `json:"id" v:"required|length:24,24#id长度错误"`
	Doc    map[string]interface{} `json:"doc" v:"required"`
	Fields []string               `json:"fields"`
}