valueCtx的value键值对存放结构体，无法读取结构体字段

import (
    "context"
    "fmt"
    "reflect"
)

type MyRequest struct {
    Url string
    Method string
    Params map[string]interface{}
}

func main() {
    params := make(map[string]interface{})
    rootRequest := MyRequest{
        Url: "https://localhost:8080/getinfo",
        Method: "Post",
        Params: params,
    }
    httpCtx := context.WithValue(context.Background(), "request", rootRequest)
    value1 := httpCtx.Value("request")
    fmt.Println(reflect.TypeOf(value1))
    fmt.Println(value1.Url)
}

如上代码，fmt.Println(reflect.TypeOf(value1))打印结果为main.MyRequest，但是fmt.Println(value1.Url)却会报错：

value1.Url undefined (type interface {} is interface with no methods)